MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

19-1085; Rev 1; 10/96
Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
________________General Description
The MAX1601/MAX1604 DC power-switching ICs con-
tain a network of low-resistance MOSFET switches that
deliver selectable VCC and VPP voltages to two
CardBus or PC Card host sockets. Key features include
ultra-low-resistance switches, small packaging, soft-
switching action, and compliance with PCMCIA specifi-
cations for 3V/5V switching. 3.3V-only power switching
for fast, 32-bit CardBus applications is supported in two
ways: stiff, low-resistance 3.3V switches allow high 3.3V
load currents (up to 1A); and completely independent
internal charge pumps let the 3.3V switch operate nor-
mally, even if the +5V and +12V supplies are discon-
nected or turned off to conserve power. The internal
charge pumps are regulating types that draw reduced
input current when the VCC switches are static. Also,
power consumption is automatically reduced to 10µA
max when the switches are programmed to high-Z or
GND states over the serial interface, unlike other solu-
tions that may require a separate shutdown-control
input.
Other key features include guaranteed specifications for
output current limit level, and guaranteed specifications
for output rise/fall times (in compliance with PCMCIA
specifications). Reliability is enhanced by thermal-over-
load protection, accurate current limiting, an overcur-
rent-fault flag output, undervoltage lockout, and extra
ESD protection at the VCC/VPP outputs. The SMBus ser-
ial interface is flexible, and can tolerate logic input levels
in excess of the positive supply rail.
The MAX1604 and MAX1601 are identical, except
for the MAX1604’s VY switch, which has roughly three-
times the on-resistance (typically 140m).The
MAX1601/MAX1604 fit two complete CardBus/PCMCIA
switches into a space-saving, narrow (0.2in. or 5mm
wide) SSOP package.
________________________Applications
Desktop Computers Data Loggers
Notebook Computers Digital Cameras
Docking Stations
Printers
Handy-Terminals
PCMCIA Read/Write Drives
Pin Configuration appears on last page.
SMBus is a trademark of Intel Corp.
____________________________Features
o Supports Two CardBus Sockets
o 1A, 0.08Max VY VCC Switch (MAX1601 only)
1A, 0.14Max VX VCC Switch
o Soft Switching for Low Inrush Surge Current
o Overcurrent Protection
o Overcurrent/Thermal-Fault Flag Output
o Thermal Shutdown at Tj = +150°C
o Independent Internal Charge Pumps
o Break-Before-Make Switching Action
o 10µA Max Standby Supply Current
o 5V and 12V Not Required for Low-RDS(ON) 3.3V
Switching
o Complies with PCMCIA 3V/5V Switching
Specifications
o Super-Small, 28-Pin SSOP Package
(0.2in. or 5mm wide)
o System Management Bus (SMBus) Serial
Interface
_______________Ordering Information
PART
MAX1601EAI
MAX1604EAI
TEMP. RANGE
-40°C to +85°C
-40°C to +85°C
PIN-PACKAGE
28 SSOP
28 SSOP
__________Simplified Block Diagram
12IN
VY
VY
VX
VX
VL
SMBCLK
SMBDATA
SMBSUS
GND
12IN
VY
VX
MAX1601/MAX1604
VDD
DECODE
LOGIC
ADDRESS
SELECT
OVERCURRENT
AND
THERMAL
SHUTDOWN
VPPA
VCCA
VCCA
VCCA
SMBALERT
ADR
VPPB
VCCB
VCCB
VCCB
________________________________________________________________ Maxim Integrated Products 1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
ABSOLUTE MAXIMUM RATINGS
Inputs/Outputs to GND
(VL, VX, VY, VCCA, VCCB) (Note 1)........................-0.3V, +6V
VPP Inputs/Outputs to GND
(12INA, 12INB, VPPA, VPPB) (Note 1) ..................-0.3V, +15V
Inputs and Outputs to GND (SMBCLK, SMBDATA,
SMBSUS, SMBALERT) (Note 1) ..............................-0.3V, +6V
ADR Input to GND ...........................................-0.3V, (VL + 0.3V)
VCCA, VCCB Output Current (Note 2).....................................4A
VPPA, VPPB Output Current (Note 2) ...............................250mA
VCCA, VCCB Short Circuit to GND ............................Continuous
VPPA, VPPB Short Circuit to GND..............................Continuous
Continuous Power Dissipation (TA = +70°C)
SSOP (derate 9.52mW/°C above +70°C) ....................762mW
Operating Temperature Range
MAX1601EAI/MAX1604EAI .............................-40°C to +85°C
Storage Temperature Range .............................-65°C to +160°C
Lead Temperature (soldering, 10sec) .............................+300°C
Note 1: There are no parasitic diodes between any of these pins, so there are no power-up sequencing restrictions (for example,
logic input signals can be applied even if all of the supply voltage inputs are grounded).
Note 2: VCC and VPP outputs are internally current-limited to safe values. See the Electrical Characteristics table.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional
operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to
absolute maximum rating conditions for extended periods may affect device reliability.
ELECTRICAL CHARACTERISTICS
(VL = VY = 3.3V, VX = 5V, 12INA = 12INB = 12V, TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
POWER-SUPPLY SECTION
Input Voltage Range
Undervoltage Lockout Threshold
VX, VY or VL
12INA, 12INB
VL falling edge
12IN falling edge
12IN rising edge
3.0 5.5
11 13
2.4 2.5 2.8
1.8 3.0
5 8 10
V
V
VX, VY falling edge
1.4 2.5 2.8
Standby Supply Current
VX or VY, all switches 0V or high-Z,
control inputs = 0V or VL, TA = +25°C
1 µA
VY Quiescent Supply Current
Any combination of VY switches on,
control inputs = 0V or VL, no VCC loads
20 100 µA
VX Quiescent Supply Current
Any combination of VX switches on,
control inputs = 0V or high-Z, no VCC loads
20 100 µA
12IN_ Standby Supply Current
12INA tied to 12INB, all switches 0V or high-Z,
control inputs = 0V or VL, TA = +25°C
1 µA
12IN_ Quiescent Supply Current
12INA tied to 12INB, VPPA and VPPB 12V switches on,
control inputs = 0V or VL, no VPP loads
15 100 µA
VL Standby Supply Current
VL Quiescent Supply Current
VL Fall Rate
All switches 0V or high-Z, control inputs = 0V or VL,
TA = +25°C
Any combination of switches on
When using VL as shutdown pin (Note 3)
4 10 µA
25 150 µA
0.05 V/µs
VCC SWITCHES
Operating Output Current Range VCCA or VCCB, VX = VY = 3V to 5.5V
0 1A
On-Resistance, VY Switches
12INA = 12INB = 0V to 13V,
VY = 3V, VX = 0V to 5.5V,
ISWITCH = 1A, TA = +25°C
MAX1601
MAX1604
0.06 0.08
0.14 0.24
On-Resistance, VX Switches
12INA = 12INB = 0V to 13V, VX = 4.5V, VY = 0V to 5.5V,
ISWITCH = 1A, TA = +25°C
0.10 0.14
2 _______________________________________________________________________________________


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
ELECTRICAL CHARACTERISTICS (continued)
(VL = VY = 3.3V, VX = 5V, 12INA = 12INB = 12V, TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
Output Current Limit
VCCA or VCCB
1.2 4.0 A
Output Sink Current
VCCA or VCCB < 0.4V, programmed to 0V state
20
mA
Output Leakage Current
VCCA or VCCB forced to 0V, high-Z state,
TA = +25°C
10 µA
Output Propagation Delay
Plus Rise Time
VCCA or VCCB, 0V to VX or VY, CL = 30µF,
RL = 25, 50% of input to 90% of output, TA = +25°C
2 10 ms
Output Rise Time
VCCA or VCCB, 0V to VX or VY, CL = 1µF,
RL = open circuit, 10% to 90% points, TA = +25°C
100 1200
µs
Output Propagation Delay
Plus Fall Time
VCCA or VCCB, VX or VY to 0V, CL = 30µF,
RL = open circuit, 50% of input to 10% of output,
TA = +25°C
60 100 ms
Output Fall Time
VCCA or VCCB, VX or VY to 0V, CL = 1µF,
RL = 25, 90% to 10% points
6 ms
VPP SWITCHES
Operating Output Current Range
On-Resistance, 12V Switches
On-Resistance, VPP = VCC Switches
Output Current Limit
Output Sink Current
VPPA or VPPB
12IN = 11.6V, ISWITCH = 100mA, TA = +25°C
Programmed to VX (5V) or VY (3.3V), TA = +25°C
VPPA or VPPB, programmed to 12V
VPPA or VPPB < 0.4V, programmed to 0V state
0 120 mA
0.70 1
1 3
130 200 260 mA
10 mA
Output Leakage Current
VPPA or VPPB forced to 0V, high-Z state,
TA = +25°C
10 µA
Output Propagation Delay
Plus Rise Time
Output Rise Time
Output Propagation Delay
Plus Fall Time
Output Fall Time
INTERFACE AND LOGIC SECTION
VPPA or VPPB, 0V to 12IN_, CL = 0.1µF,
50% of input to 90% of output, TA = +25°C
VPPA or VPPB, 0V to 12IN_, CL = 0.1µF,
10% to 90% points, TA = +25°C
VPPA or VPPB, 12IN_ to 0V, CL = 0.1µF,
50% of input to 10% of output, TA = +25°C
VPPA or VPPB, 12IN_ to 0V, CL = 0.1µF,
90% to 10% points
1.2 30 ms
100 800
µs
9 60 ms
1 ms
SMBALERT Signal Propagation
Delay
VCC_ or VPP_, load step to SMBALERT output,
50% point to 50% point (Note 3)
3 µs
SMBALERT Output Low Voltage
SMBALERT Output Leakage Current
Thermal Shutdown Threshold
Logic Input Low Voltage
ISINK = 1mA, low state
VSMBALERT = 5.5V, high state
Hysteresis = +20°C (Note 4)
SMBSUS, SMBCLK, SMBDATA
0.4 V
-0.1 0.1 µA
150 °C
0.8 V
Logic Input High Voltage
SMBSUS, SMBCLK, SMBDATA
2.2
V
Logic Output Low Voltage
SMBDATA, ISINK = 4mA
0.4 V
_______________________________________________________________________________________ 3


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
ELECTRICAL CHARACTERISTICS (continued)
(VL = VY = 3.3V, VX = 5V, 12INA = 12INB = 12V, TA = 0°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.)
PARAMETER
CONDITIONS
MIN TYP MAX UNITS
SMB Input Capacitance
SMBSUS, SMBCLK, SMBDATA
5 pF
SMBCLK Clock Frequency
SMBus spec = 10kHz min
DC 100 kHz
SMBCLK Clock Low Time
tLOW 10% to 10% points
4.7 µs
SMBCLK Clock High Time
tHIGH 90% to 90% points
4 µs
SMB Repeated Start-Condition
Setup Time
tSU:STA 90% to 90% points
250 ns
SMB Start-Condition Hold Time
SMB Stop-Condition Setup Time
SMB Data Valid to SMBCLK Rising-
Edge Time
tHD:STA 10% of SMBDATA to 90% of SMBCLK
tSU:STO 90% of SMBCLK to 10% of SMBDATA
tSU:DAT 10% or 90% of SMBDATA to
10% of SMBCLK
4
4
500
µs
µs
ns
SMB Data Hold Time
Bus Free Time
ADR Input Low Voltage
ADR Input High Voltage
Logic Input Bias Current
tHD:DAT (Note 5)
tBUF between start and stop conditions
ADR, SMBSUS, SMBCLK, SMBDATA
0 ns
4.7 µs
0.6 V
1.5 V
-1 1 µA
SCL Fall to SDA Valid
(Master Clocking-In Data)
100 1000
ns
Start-Condition Setup
4.7 µs
Note 3: Not production tested.
Note 4: Thermal limit not active in standby state (all switches programmed to GND or high-Z state).
Note 5: A transition must internally provide at least a hold time in order to bridge the undefined region (300ns max) of the falling
edge of SMBCLK.
4 _______________________________________________________________________________________


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
ELECTRICAL CHARACTERISTICS
(VL = VY = 3.3V, VX = 5V, 12INA = 12INB = 12V, TA = -40°C to +85°C, unless otherwise noted.)
PARAMETER
CONDITIONS
POWER-SUPPLY SECTION
Input Voltage Range
VX, VY or VL
12INA, 12INB
VL falling edge, hysteresis = 1%
12IN falling edge
Undervoltage Lockout Threshold
12IN rising edge
VX, VY falling edge
Standby Supply Current
VX or VY, all switches 0V or high-Z,
control inputs = 0V or VL
MIN TYP MAX UNITS
3.0 5.5
V
11 13
2.3 2.9
1.8
V
5 10
1.4 2.9
15 µA
VY Quiescent Supply Current
Any combination of VY switches on,
control inputs = 0V or VL, no VCC loads
100 µA
VX Quiescent Supply Current
Any combination of VX switches on,
control inputs = 0V or high-Z, no VCC loads
100 µA
12IN_ Standby Supply Current
12INA tied to 12INB, all switches 0V or high-Z,
control inputs = 0V or VL
15 µA
12IN_ Quiescent Supply Current
12INA tied to 12INB, VPPA and VPPB 12V switches on,
control inputs = 0V or VL, no VPP loads
100 µA
VL Standby Supply Current
All switches 0V or high-Z, control inputs = 0V or VL
15 µA
VL Quiescent Supply Current
Any combination of switches on
INTERFACE AND LOGIC SECTION
SMBALERT Output Low Voltage ISINK = 1mA, low state
Logic Input Low Voltage
SMBCLK, SMBDATA, SMBSUS
Logic Input High Voltage
SMBCLK, SMBDATA, SMBSUS
Logic Output Low Voltage
SMBDATA, ISINK = 4mA
ADR Input Low Voltage
ADR Input High Voltage
150 µA
0.4 V
0.8 V
2.2 V
0.4 V
0.6 V
1.5 V
_______________________________________________________________________________________ 5


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
__________________________________________Typical Operating Characteristics
(VL = VY = 3.3V, VX = 5V, 12IN, TA = +25°C, unless otherwise noted.)
6
VCC_ 4
(V) 2
0
CONTROL 5
INPUT
(V) 0
VCC_ SWITCHING (RISE)
3
VCC_
(V)
2
1
0
CONTROL 5
INPUT
(V) 0
VCC_ SWITCHING (RISE)
CL = 30µF, RL = 25
200µs/div
VCC_ SWITCHING (FALL)
6
VCC_
(V)
4
2
0
CONTROL 5
INPUT
(V) 0
CL = 1µF, RL =
500µs/div
VCC_ SWITCHING (FALL)
6
4
VCC_
(V)
2
0
CONTROL 5
INPUT
(V) 0
CL = 33µF, RL =
10ms/div
15
VPP_
(V)
10
5
0
CONTROL 5
INPUT
(V) 0
VPP_ SWITCHING (RISE)
CL = 1µF, RL = 25
10ms/div
15
VPP_
(V)
10
5
0
CONTROL 5
INPUT
(V) 0
VPP_ SWITCHING (FALL)
CL = 0.1µF, RL =
200µs/div
CL = 0.1µF, RL =
2ms/div
6 _______________________________________________________________________________________


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
_____________________________Typical Operating Characteristics (continued)
(VL = VY = 3.3V, VX = 5V, 12IN, TA = +25°C, unless otherwise noted.)
4
VCC_ 2
(V) 0
VCC_ CURRENT LIMITING
INPUT CURRENT (VCC OUTPUT SHORTED)
2.0
1.5
IVY 1.0
(A)
0.5
0
2ms/div
CL = 1µF, RESISTIVE OVERLOAD, RL = 1
VPP_ CURRENT LIMITING
10
VPP_
(V) 5
0
CL = 1µF, RL = 50
2ms/div
4
VL
(V) 2
0
1ms/div
INPUT CURRENT (VPP OUTPUT SHORTED)
10
VPP_
(V)
5
0
300
I12IN_ 200
(mA) 100
0
RL = 0.1
VCC_ SHUTDOWN RESPONSE
100µs/div
4
VCC_ 2
(V)
0
100µs/div
CIRCUIT OF FIGURE 2
_______________________________________________________________________________________ 7


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
_____________________________Typical Operating Characteristics (continued)
(VL = VY = 3.3V, VX = 5V, 12IN, TA = +25°C, unless otherwise noted.)
110
105
100
95
90
85
80
75
70
65
60
0
VX ON-RESISTANCE
vs. VCC_ LOAD CURRENT
TA = +85°C
TA = +25°C
TA = -40°C
200 400 600 800
VCC_ LOAD CURRENT (mA)
1000
MAX1601
VY ON-RESISTANCE vs. CURRENT
80
75
70 TA = +85°C
65
60
55 TA = +25°C
50
45
40 TA = -40°C
35
30
0
200 400 600 800 1000
CURRENT (mA)
MAX1604
VY ON-RESISTANCE vs. CURRENT
165
160 TA = +85°C
155
150
145
140 TA = +25°C
135
130
125
120
115
0
TA = -40°C
200 400 600 800 1000
CURRENT (mA)
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
0
12IN_ ON-RESISTANCE vs. CURRENT
725
720
VPPA
715
710
705
700 VPPB
695
690
685
0
20 40 60 80 100 120 140
CURRENT (mA)
12IN_ ON-RESISTANCE vs. TEMPERATURE
950
900
850
800
750
700
650
600
550
-40 -20 0 20 40 60 80 100
TEMPERATURE (°C)
VX, VY SUPPLY CURRENT
vs. INPUT VOLTAGE
VX
VY
12IN SUPPLY CURRENT
vs. INPUT VOLTAGE
7
6
5
4
3
VL SUPPLY CURRENT
vs. VL INPUT VOLTAGE
70
VX = VY = 0V
60 12IN
50
40 NORMAL
OPERATION
30
2 20
1 234 5
INPUT VOLTAGE (V)
6
1
0
0 2 4 6 8 10 12
INPUT VOLTAGE (V)
10
0
0
SHUTDOWN
1 2 34 5
INPUT VOLTAGE (V)
6
8 _______________________________________________________________________________________


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
______________________________________________________________Pin Description
PIN
1, 25
2, 3,
26, 27
4
5
6, 8, 10
7, 22, 24
9, 18, 20
11
12
13
14
15
16
17
19, 21, 23
28
NAME
GND
N.C.
12INA
VPPA
VX
VCCA
VCCB
VPPB
12INB
ADR
SMBSUS
SMBCLK
SMBDATA
SMBALERT
VY
VL
Ground
FUNCTION
No internal connection
+12V Supply Voltage Input, internally connects to channel A VPP switch. Tie to VPPA if not used.
Channel A VPP Output
VX Supply-Voltage Inputs. VX pins must be connected together. Input range is 3V to 5.5V. VX is
normally connected to 5V.
Channel A VCC Outputs
Channel B VCC Outputs
Channel B VPP Output
+12V Supply Voltage Input, internally connects to channel B VPP switch. Tie to VPPB if not used.
Address Input, sets SMBus address location. See Table 1 for address selection.
SMBus Suspend-Mode Control Input. The device will execute commands previously stored in
the normal-mode register if SMBSUS is high, or will execute commands previously stored in the
suspend-mode register if SMBSUS is low.
SMBus Clock Input
SMBus Data Input/Output, open drain
Fault-Detection Interrupt Output. SMBALERT goes low if either channel VCC or VPP switch is
current limiting or undervoltage lockout, or if the thermal protection circuit is activated.
SMBALERT is an open-drain output that requires an external pull-up resistor.
VY Supply-Voltage Inputs. VY pins must be connected together. Input range is 3V to 5.5V. VY is
normally connected to 3V.
Logic Supply-Voltage Inputs. Connect to the +3.3V or +5V host system supply. VL can be sup-
plied via the output of a CMOS-logic gate to produce an overriding shutdown. When used as a
shutdown input, VL should have a 1kseries resistor with a 0.1µF capacitor to ground (Figure 2).
Note that VL must be greater than undervoltage lockout for any switches to be turned on.
_______________________________________________________________________________________ 9


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
12IN VB12
1/2 MAX1601/MAX1604
VPPA
CHARGE
PUMP
CURRENT
LIMIT
3
40
VB3
VY
0.08*
VY
CHARGE
PUMP
CURRENT
LIMIT
VX
VB5 0.14
VX
VCCA
VCCA
VCCA
20
CHARGE
PUMP
CURRENT
LIMIT
SMBCLK
SMBDATA
SMBSUS
ADR
SHDN
SMB
VDD
VL
THERMAL
SHUTDOWN
SMBALERT
GND
*0.24FOR THE MAX1604
Figure 1. Functional Diagram (one channel of two)
10 ______________________________________________________________________________________


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
_______________Detailed Description
The MAX1601/MAX1604 power-switching ICs contain a
network of low-resistance MOSFET switches that deliver
selectable VCC and VPP voltages to two Cardbus or
PC Card host sockets. The MAX1601/MAX1604 differ
only in the VY switch on-resistance. Figure 1 is the
detailed block diagram.
The power-input pins (VY, VX, 12IN_) are completely
independent. Low inrush current is guaranteed by con-
trolled switch rise times. VCC’s 100µs minimum output
rise time is 100% tested with a 1µF capacitive load, and
VPP’s 1ms minimum rise time is guaranteed with a 0.1µF
load. These respective capacitive loads are chosen as
worst-case card-insertion parameters. The internal
switching control allows VCC and VPP rise times to be
controlled, and makes them nearly independent of resis-
tive and capacitive loads (see rise-time photos in the
Typical Operating Characteristics). Fall times are a
function of loading, and are compensated by internal
circuitry.
Power savings is automatic: internal charge pumps draw
very low current when the VCC switches are static.
Standby mode reduces switch supply current to 1µA.
Driving the VL pin low with an external logic gate (master
shutdown) reduces total supply current to1µA (Figure 2).
Operating Modes
The MAX1601/MAX1604 have three operating modes:
normal, standby, and shutdown. Normal mode supplies
the selected outputs with their appropriate supply volt-
ages. Standby mode places all switches at ground, high
impedance, or a combination of the two. Shutdown mode
turns all switches off, and puts the VCC and VPP outputs
into a high-impedance state. Pull VL low to enter shutdown
mode. To ensure a 0.05V/µs fall rate on VL, use a 1k
series resistor and a 0.1µF capacitor to ground (Figure 2).
Overcurrent Protection
Peak detecting circuitry protects both the VCC and
VPP switches against overcurrent conditions. When
current through any switch exceeds the internal current
limit (4A for VCC switches and 200mA for VPP switch-
es), the switch turns off briefly, then turns on again at
the controlled rise rate. If the overcurrent condition
lasts more than 2µs, the SMBALERT output latches
MASTER
SHUTDOWN
74HC04
1k
0.1µF
3.3V
VY VPPA
VL VCCA
MAX1601
MAX1604
VPPB
VCCB
TO
SOCKETS
A AND B
Figure 2. Master Shutdown Circuit
low. A continuous short-circuit condition results in a
pulsed output current until thermal shutdown is
reached. SMBALERT is open-drain and requires an
external pull-up resistor.
Thermal Shutdown
If the IC junction temperature rises above +150°C, the
thermal shutdown circuitry opens all switches, including
the GND switches, and SMBALERT is pulled low. When
the temperature falls below +130°C, the switches turn
on again at the controlled rise rate. If the overcurrent
condition remains, the part cycles between thermal
shutdown and overcurrent.
Undervoltage Lockout
If the VX or VY switch input voltage drops below 1.5V,
the associated switch turns off and SMBALERT goes
low. For example, if VY is 3.3V and VX is 0V, and if the
interface controller selects VY, the VCCA output will be
3.3V. If VX is selected, VCCA changes to a high-imped-
ance output and SMBALERT goes low.
When a voltage is initially applied to 12IN_, it must be
greater than 8V to allow the switch to operate.
Operation continues until the voltage falls below 2V (the
VPP output is high impedance).
When VL drops to less than 2.3V, all switches are
turned off and the VCC and VPP outputs are high
impedance.
______________________________________________________________________________________ 11


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
______SMBus™ Interface Operation
The SMBus serial interface is a two-wire interface with
multi-mastering capability, intended to control low-
speed peripheral devices in low-power portable equip-
ment applications. SMBus is similar to I2C™ and
AccessBus, but has slightly different logic threshold
voltage levels, different fixed addresses, and a sus-
pend-mode register capability. To obtain a complete
set of specifications on the SMBus interface, call Intel at
(800) 253-3696 and ask for product code SBS5220.
SMBus Addressing
These dual-channel PC Card switch devices respond to
two of four different addresses, depending on the state
of the ADR address pin. Normal writing to the device is
done by transmitting one of four addresses, followed by
a single data byte, to program the channel selected.
Write transmissions to the interrupt pointer address are
not supported by these devices. Reading from the
device is done by transmitting one of two addresses cor-
Table 1. SMBus Addressing
SMB
ADDRESS
ADR PIN
0001100 Don’t care
1010000 Grounded
1010001 Grounded
1010010 Tied to VL
1010011 Tied to VL
WRITE
FUNCTION
N/A
Channel A
Channel B
Channel A
Channel B
READ FUNCTION
Interrupt Pointer
Channel A/B faults
Channel A/B faults
Channel A/B faults
Channel A/B faults
responding to either the A channel address (which will
provide data about faults for both A and B channels) or
to the interrupt pointer address (discussed later).
The normal start condition consists of a high-to-low
transition on SMBDATA while SMBCLK is high. The
7-bit address is followed by a bit that designates a read
or write operation: high = read, low = write. If the 7-bit
address matches one of the supported function
addresses, the IC issues an acknowledge pulse by
pulling the SMBDATA line low. If the address is not
valid, the IC stays off of the bus and ignores any data
on the bus until a new start condition is detected. Once
the IC receives a valid address that includes a write bit,
it expects to receive one additional byte of data. If a
stop condition or new start condition is detected before
a complete byte of data is clocked in, the IC interprets
this as an error and all of the data is rejected and lost.
SMBDATA and SMBCLK are Schmitt triggered and can
accommodate slower edges. However, rising edges
should still be faster than 1µs, and falling edges should
be faster than 300ns.
SMBus Write Operations
If the IC receives a valid address immediately followed
by a write bit, the IC becomes a slave receiver. The
slave IC generates a first acknowledge after the
address and write bit, and a second acknowledge after
the command byte. A stop condition following the com-
mand (data) byte causes immediate execution of the
command, unless the data included a low SUS/OP bit.
If the data included a low SUS/OP bit, the command is
stored in the suspend-mode register and is executed
only when the SMBSUS pin is pulled low (Figure 3).
Table 2. Command Format for Channel A Write Operations (address 1010000 or 1010010)
BIT NAME POR STATE
FUNCTION
7 (MSB) OP/SUS
0
Operate/suspend bit. Selects which latch receives data: high = operation,
low = suspend.
6 VCCAON
0 Turns on VCCA when high, pulls VCCA to GND when low.
5 VCCA3/5
0 If VCCA is on, a high connects VY to VCCA, and a low connects VX to VCCA.
4 VCCAHIZ
0 Puts VCCA in a high-impedance state when high. Overrides VCCAON.
3 VPPAON
0 Turns on VPPA when high, pulls VPPA to GND when low.
2 VPPAPGM 0 If VPPA is on, a high connects VPPA to 12INA, and a low connects VPPA to VCCA.
1 VPPAHIZ
0 Puts VPPA in a high-impedance state when high. Overrides VPPAON.
0 (LSB) MASKFLT
0 Masks fault interrupts from both channel A and channel B when high.
I2C is a trademark of Philips Corp.
SMBus is a trademark of Intel Corp.
12 ______________________________________________________________________________________


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
Table 3. Command Format for Channel B Write Operations (address 1010001 or 1010011)
BIT
7 (MSB)
6
5
4
3
2
1
0 (LSB)
NAME POR STATE
FUNCTION
OP/SUS
0
Operate/suspend bit. Selects which latch receives data: high = operation,
low = suspend.
VCCBON
0 Turns on VCCB when high, pulls VCCB to GND when low.
VCCB3/5
0 If VCCB is on, a high connects VY to VCCB, and a low connects VX to VCCB.
VCCBHIZ
0 Puts VCCB in a high-impedance state when high. Overrides VCCBON.
VPPBON
0 Turns on VPPB when high, pulls VPPB to GND when low.
VPPBPGM 0 If VPPB is on, a high connects VPPB to 12INB, and a low connects VPPB to VCCB.
VPPBHIZ
0 Puts VPPB in a high-impedance state when high. Overrides VPPBON.
RFU 0 Reserved for future use.
Table 4. Read Format for Interrupt Pointer Address (0001100)
BIT
7 (MSB)
6
5
4
3
2
1
0 (LSB)
NAME
ADD7
ADD6
ADD5
ADD4
ADD3
ADD2
ADD1
ADD0
POR STATE
0
0
0
0
0
0
0
0
FUNCTION
ADD7 to ADD1 provide a return address for any interrupt query. For these devices, the
return addresses are:
1010000 = Channel A, ADD = low
1010001 = Channel B, ADD = low
1010010 = Channel A, ADD = high
1010011 = Channel B, ADD = high
Table 5. Read Format for Power Switch Address (1010000 or 1010010)
BIT
7 (MSB)
6
5
4
3
2
1
0 (LSB)
NAME POR STATE
CATFAULT
0
FAULT1
0
FAULT2
0
FAULT3
0
FAULT4
0
SIG/DUAL
0
RFU 0
RFU 0
LATCHED?
Y
Y
Y
Y
Y
N
N
N
FUNCTION
Indicates catastrophic (thermal or undervoltage lockout) fault when high.
Indicates VCCA overcurrent/undervoltage lockout when high.
Indicates VPPA overcurrent/undervoltage lockout when high.
Indicates VCCB overcurrent/undervoltage lockout when high.
Indicates VPPB overcurrent/undervoltage lockout when high.
Indicates dual part (single-channel devices would read 1).
Reserved for future use.
Reserved for future use.
______________________________________________________________________________________ 13


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
AB
C D EF
tLOW tHIGH
SMBCLK
G
H IJ
K LM
SMBDATA
tSU:STA tHD:STA
tSU:DAT
tHD:DAT
tSU:STO tBUF
A = START CONDITION
B = MSB OF ADDRESS CLOCKED INTO SLAVE
C = LSB OF ADDRESS CLOCKED INTO SLAVE
D = R/W BIT CLOCKED INTO SLAVE
E = SLAVE PULLS SMBDATA LINE LOW
F = ACKNOWLEDGE BIT CLOCKED INTO MASTER
G = MSB OF DATA CLOCKED INTO SLAVE (OP/SUS BIT)
H = LSB OF DATA CLOCKED INTO SLAVE
I = SLAVE PULLS SMBDATA LINE LOW
J = ACKNOWLEDGE CLOCKED INTO MASTER
K = ACKNOWLEDGE CLOCK PULSE
L = STOP CONDITION, DATA EXECUTED BY SLAVE
M = NEW START CONDITION
Figure 3. SMBus Write Timing Diagram
SMBus Read Operations
If the IC receives a valid address that includes a read
bit, the IC becomes a slave transmitter. After receiving
the address data, the IC generates an acknowledge
during the acknowledge clock pulse and drives the
SMBDATA line in sync with SMBCLK. The SMB proto-
col requires that the master end the read transmission
by not acknowledging during the acknowledge bit of
SMBCLK. These PC Card ICs support the repeated
start-condition method for changing data-transfer direc-
tion; that is, a write transmission followed by a repeated
start instead of a stop condition prepares the IC for
data reading (Figure 4).
SMBus Interrupts
These PC Card power-switch ICs are slave devices
only, and never initiate communications except by
asserting an interrupt (by pulling SMBALERT low).
Interrupts are generated only for reporting fault condi-
tions, including overcurrent at VCCA, VCCB, VPPA, or
VPPB, undervoltage lockout, and IC thermal overload. If
an interrupt occurs, it can be an indication of impend-
ing system failure. The host system can react by going
into suspend mode or taking other action. It can come
back later to interrogate the IC via the interrupt pointer
to determine status or perform corrective action (such
as disabling the appropriate power switch that might
be connected to a shorted PC card). The fastest
method for turning off the switches in response to a
fault condition is to cycle the voltage on VL in order to
generate a power-on reset (which clears all of the
SMBus registers). Note that the SMBus registers retain
their data even if the main VX/VY supplies are turned
off, provided that VL remains powered.
When a fault occurs, SMBALERT is immediately assert-
ed and latched low. If the fault is momentary and disap-
pears before the IC is serviced, the data is still latched
in the interrupt pointer and SMBALERT remains assert-
ed. Normally, the master (host system or PCMCIA digi-
tal controller) now sends out the interrupt pointer
address (00011000) followed by a read bit. SMBALERT
is cleared and the PC Card IC responds by putting out
its address on the bus. If the fault persists, SMBALERT
is re-asserted, but the data in the fault registers is not
reloaded. The data in the fault latches only reflects the
first time SMBALERT is asserted.
When the part enters operating mode, a false interrupt
flag may be issued. The user needs to send the inter-
rupt address to clear the false interrupt.
Normally, the master sends out the appropriate PC Card
switch address on the bus, followed by a read bit. The
data in the fault registers is then clocked out onto the
bus (which also clears the fault registers). If the fault
persists, the fault bits and SMBALERT are latched
again.
14 ______________________________________________________________________________________


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
AB
C D EF G
tLOW tHIGH
SMBCLK
H I JK
SMBDATA
tSU:STA tHD:STA
tSU:DAT
A = START CONDITION
B = MSB OF ADDRESS CLOCKED INTO SLAVE
C = LSB OF ADDRESS CLOCKED INTO SLAVE
D = R/W BIT CLOCKED INTO SLAVE
E = SLAVE PULLS SMBDATA LINE LOW
F = ACKNOWLEDGE BIT CLOCKED INTO MASTER
G = MSB OF DATA CLOCKED INTO MASTER
H = LSB OF DATA CLOCKED INTO MASTER
tSU:STO tBUF
I = ACKNOWLEDGE CLOCK PULSE
J = STOP CONDITION
K = NEW START CONDITION
Figure 4. SMBus Read Timing Diagram
The interrupt pointer address provides quick fault iden-
tification for simple slave devices that lack the complex,
expensive logic needed to be a bus master. The host
can read the interrupt pointer to determine which slave
device generated an SMBALERT interrupt signal. The
interrupt pointer address can activate several different
slave devices simultaneously, similar to an I2C general
call. Any slave device that generated an interrupt
attempts to identify itself by putting its own address on
the bus during the first read byte. If more than one slave
attempts to respond, bus arbitration rules apply and the
device with the lower address code wins. The losing
device won’t generate an acknowledge and will contin-
ue to hold the SMBALERT line low until serviced, which
implies that the host interrupt input must be level
sensitive.
__________Applications Information
Changing SMBCLK and SMBDATA
Simultaneously
When clocking data into the MAX1601/MAX1604, SMB-
DATA must not fall before SMBCLK. Otherwise, the
MAX1601/MAX1604 may interpret this as a start condi-
tion. Even when SMBDATA and SMBCLK fall at the
same instant, different fall times for the two signals may
cause the erroneous generation of a start condition. To
ensure that SMBDATA transitions after the falling edge of
SMBCLK, add an RC network to SBMDATA (Figure 6).
1k
VL
0.1µF
MAX1601
+5V VX MAX1604
Supply Bypassing
Bypass the VY, VX, and 12IN_ inputs with ceramic 0.1µF
capacitors. Bypass the VCC_ and VPP_ outputs with a
0.1µF capacitor for noise reduction and ESD protection.
Power-Up
Apply power to the VL input before any of the switch
inputs. If VX, VY, or 12IN receive power before VL rises
above 2.8V, the supply current may be artificially high
(about 5mA). When the voltage on VL is greater than
2.8V (operating mode), the part consumes its specified
24µA. To avoid power sequencing, diode-OR VX and
VY to VL through a 1kresistor (Figure 5). Take care
not to allow VL to drop below the 2.8V maximum under-
voltage lockout threshold.
VY
Figure 5. Powering from Either VX or VY
+5V
CIRRUS LOGIC
CL-PD6730
SMBDATA
SMBCLK
10k
PULL-UP
1.5k
100pF
SMBDATA
MAX1601
MAX1604
SMBCLK
Figure 6. Application with Cirrus Logic Interface
______________________________________________________________________________________ 15


MAX1604 (Maxim)
Dual-Channel CardBus and PCMCIA Power Switches with SMBus Serial Interface

No Preview Available !

Click to Download PDF File for PC

Dual-Channel CardBus and PCMCIA
Power Switches with SMBus™ Serial Interface
__________________Pin Configuration ___________________Chip Information
TOP VIEW
GND 1
N.C. 2
N.C. 3
12INA 4
VPPA 5
VX 6
VCCA 7
VX 8
VCCB 9
VX 10
VPPB 11
12INB 12
ADR 13
SMBSUS 14
MAX1601
MAX1604
SSOP
28 VL
27 N.C.
26 N.C.
25 GND
24 VCCA
23 VY
22 VCCA
21 VY
20 VCCB
19 VY
18 VCCB
17 SMBALERT
16 SMBDATA
15 SMBCLK
TRANSISTOR COUNT: 4372
________________________________________________________Package Information
EH
C
α
L
INCHES
DIM
MIN MAX
MILLIMETERS
MIN MAX
A 0.068 0.078 1.73 1.99
A1 0.002 0.008 0.05 0.21
B 0.010 0.015 0.25 0.38
C 0.004 0.008 0.09 0.20
D SEE VARIATIONS
E 0.205 0.209 5.20 5.38
e 0.0256 BSC
0.65 BSC
H 0.301 0.311 7.65 7.90
L 0.025 0.037 0.63 0.95
α 0˚ 8˚ 0˚ 8˚
e
B
D
A
A1
SSOP
SHRINK
SMALL-OUTLINE
PACKAGE
DIM PINS
INCHES MILLIMETERS
MIN MAX MIN MAX
D 14 0.239 0.249 6.07 6.33
D 16 0.239 0.249 6.07 6.33
D 20 0.278 0.289 7.07 7.33
D 24 0.317 0.328 8.07 8.33
D 28 0.397 0.407 10.07 10.33
21-0056A
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are
implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
16 __________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 (408) 737-7600
© 1996 Maxim Integrated Products
Printed USA
is a registered trademark of Maxim Integrated Products.




MAX1604.pdf
Click to Download PDF File