DALLAS DS1640C

DS1640/DS1640C
Personal Computer Power FET
www.dalsemi.com
FEATURES
PIN ASSIGNMENT
Contains four P channel power FET switches
that can each supply over 300 mA @ 0.2 volts
drop
Controlled directly from CMOS or TTL level
signals
Fast switching time of less than 10 µs at rated
supply current
16-pin DIP or 16-pin SOIC surface mount
package
Positive logic signal turns each FET on and
ground or low level signal turns each FET off
Off condition allows less than 50 nA of
current flow
Low control gate capacitance of less than 5
pF
FET gates can either follow inputs or be
latched
Designed for use with power supplies ranging
from +3 to +5 volts
IN1
GATE1
OUT1
LATCH
GND
OUT2
GATE2
IN2
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
IN4
GATE4
OUT4
NC
VCC
OUT3
GATE3
IN3
16-Pin DIP (300-mil)
See Mech. Drawings Section
IN1
GATE1
OUT1
LATCH
GND
OUT2
GATE2
IN2
1
2
3
4
5
6
7
8
16
15
14
13
12
11
10
9
IN4
GATE4
OUT4
NC
VCC
OUT3
GATE3
IN3
16-Pin DIP SOIC (300-mil)
See Mech. Drawings Section
PIN DESCRIPTION
VCC
GND
IN1-IN4
OUT1-OUT4
GATE1-GATE4
NC
LATCH
- +3 to +5 Volt Input
- Ground
- FET Sources
- FET Drains
- FET Control Gates
- No Connection
- Gate Inputs Latch Control
DESCRIPTION
The DS1640 contains four P channel power MOS FETs designed as switches to conserve power in
personal computer systems. When connected to power management control units, power consuming
devices like disk drives or display panel backlights can be routinely shut down to conserve battery or
main power supply energy. The P channel power MOS FETs are individually controlled and are capable
of handling 300 mA each continuously with less than 0.2 volts drop from input to output. The device
requires a +3 Û +5 volt power supply input which is used to power internal logic and to operate a gate
bias generator.
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111999
DS1640/DS1640C
OPERATION
With +3 Û +5 volts applied between the VCC pin and ground, any one of four inputs can be connected or
disconnected from its respective output based on the bias applied to the control gate (see Figure 1). A set
of four internal latches is controlled by the latch input. The logic levels passed to the FET gates are
controlled by the gate inputs and latch pin status. When the latch pin is logic 0, the gate input levels are
inverted and passed directly to the control gates, enabling the switches to be switched both independently
and asynchronously. With a transition from logic 0 to logic 1 on the latch pin, the input levels present on
the gate inputs are locked by the four internal latches, maintaining the corresponding FET gates at those
levels. As long as the latch input is maintained at logic 1, the FET gate levels are maintained. When the
latch input is returned to logic 0, the gate inputs again are inverted and passed to the FET control gates
without being latched. A TTL or CMOS logic 1 turns a switch completely on and TTL or CMOS logic 0
turns a switch completely off. The four switches can be operated independently or two or more can be
connected in parallel for added current carrying capability. The four switches contained within the
DS1640 are not designed to be operated in a linear manner. When VCC is not applied to the DS1640 or if
VCC is not within nominal limits, the output levels and current carrying capability of the four switches are
not guaranteed. When all four gate inputs are off (logic 0) the device enters a low VCC current standby
mode because the onboard charge pump is turned off. The gate and latch inputs are CMOS-compatible
throughout the entire VCC range and are TTL-compatible when VCC falls between 4.5 and 5.5V.
DS1640 BLOCK DIAGRAM Figure 1
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DS1640/DS1640C
ABSOLUTE MAXIMUM RATINGS*
Voltage on Any Pin Relative to Ground
Operating Temperature
Storage Temperature
Soldering Temperature
-0.3V to +7.0V
0°C to 70°C
-55°C to +125°C
260°C for 10 seconds
* This is a stress rating only and functional operation of the device at these or any other conditions above
those indicated in the operation sections of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods of time may affect reliability.
DC OPERATING CONDITIONS
PARAMETER
Supply Voltage
Logic 0 Input 3.0 V < VCC <
4.5 V
Logic 0 Input 4.5 V < VCC <
5.0 V
Logic 1 Input 3.0 V < VCC <
5.0 V
Source Voltage
(0°C to 70°C)
SYMBOL
VCC
VIL2
MIN
3.0
-0.3
VIL1
VIH
MAX
5.5
+0.5
UNITS
V
V
NOTES
1, 2
-0.3
+0.8
V
1
2.0
VCC +0.5
V
1, 7
VCC +0.5
V
1, 7
VSOURCE
DC ELECTRICAL CHARACTERISTICS
PARAMETER
Supply Current
Supply Current
Switch Off Leakage
Switch On Resistance
Switch Current @ VF = 200
mV
Input Leakage
Gate Input Capacitance
TYP
SYMBOL
ICC1
ICC2
ISL
RON
IS
MIN
IIL
CG
-1
SYMBOL
tSTON
Switching Time (ON → OFF)
Minimum Time to Engage
Latch
tSTOFF
tLM
TYP
0.3
0.1
0.3
DC ELECTRICAL CHARACTERISTICS
PARAMETER
Switching Time (OFF → ON)
(0°C to 70°C; VCC = +5V + 10%)
MIN
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MAX
1
1
100
0.67
300
UNITS
mA
µA
nA
Ω
mA
NOTES
3
4
+1
5
µA
pF
6
7
5
(0°C to 70°C; VCC = +5V + 10%)
TYP
MAX
10
UNITS
µs
10
50
µs
ns
NOTES
DS1640/DS1640C
NOTES:
1. All voltages are referenced to ground.
2. When VCC is below minimum limits output levels are not guaranteed.
3. ICC1 is the supply current with one or more switches on.
4. ICC2 is when all switches are off and all inputs are within 0.5V of a supply rail.
5. Each switch is capable of carrying 300 mA maximum at 200 mV forward drop.
6. Input leakage applies to the four gate inputs and the latch input only.
7. Applies to each of four gate inputs and the latch input.
Dallas Semiconductor devices are built to the highest quality standards and manufactured for long term
reliability. All DS1640 devices are made using the same quality materials and manufacturing methods.
However, consumer versions of the DS1640 are not exposed to environmental stresses that some
commercial device manufacturing flows require. Devices that are designated as consumer product have a
“C” designator in the product number. For example, the DS1640C is a consumer grade product.
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