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19-1153; Rev 0; 10/96
Dual, Current-Limited, High-Side P-Channel
Switches with Thermal Shutdown
_______________General Description
The MAX894L/MAX895L smart, dual, low-voltage,
P-channel, MOSFET power switches are intended for
high-side load-switching applications. These switches
operate with inputs from +2.7V to +5.5V, making them
ideal for both 3V and 5V systems. Internal current-
limiting circuitry protects the input supply against
overload. Thermal-overload protection limits power dis-
sipation and junction temperature.
The MAX894L/MAX895L’s maximum current limits are
500mA and 250mA, respectively. The current limit
through the switches is programmed with resistors from
SET A/SET B to ground. When the switches are on, the
quiescent supply current is a low 16
____________________________Features
©
+2.7V to +5.5V Input Range
©
Programmable Current Limits
©
Low Supply Current:
16
A I
Q
at V
IN
= 3.3V
m
0.1
m
A with Switch Off
©
Thermal Shutdown
A. When the
switches are off, the supply current decreases to 0.1
m
A.
The MAX894L/MAX895L are available in an 8-pin SO
package.
m
______________Ordering Information
TEMP.
RANGE
PIN-
PACKAGE
Dice**
8 SO
CURRENT
LIMIT
500mA
500mA
PART*
MAX894L
C/D
MAX894LESA
0°C to +70°C
________________________Applications
PCMCIA Slots
Access Bus Slots
Portable Equipment
-40°C to +85°C
MAX895L
C/D
0°C to +70°C
Dice**
250mA
MAX895LESA
-40°C to +85°C
8 SO
250mA
*To order these units in tape and reel, add (-T) to the end of the
part number.
**Dice are tested at T
A
= +25°C.
__________Typical Operating Circuit
__________________Pin Configuration
TOP VIEW
OUTPUT A
0.1
OUT A
ONB
ON/OFF
m
F
OUTPUT B
OUT B
IN
INPUT
OUT A
ONB
1
8
MAX894L
MAX895L
0.1
m
F
1
m
F
OUT B
2
IN
7
MAX894L
MAX895L
SET A
3
6
SET B
SET A
SET B
ONA
4
5
GND
R
SET
A
R
SET
B
SO
ON/OFF
ONA
GND
________________________________________________________________ Maxim Integrated Products
1
For free samples & the latest literature: http://www.maxim-ic.com, or phone 1-800-998-8800
Dual, Current-Limited, High-Side P-Channel
Switches with Thermal Shutdown
ABSOLUTE MAXIMUM RATINGS
IN to GND ...................................................................-0.3V to 6V
ONA, ONB to GND .....................................................-0.3V to 6V
SET A, SET B, OUT A, OUT B to GND ........-0.3V to (V
IN
+ 0.3V)
Maximum Continuous Switch Current
MAX894L ..........................................................................0.75A
MAX895L ........................................................................0.375A
Continuous Power Dissipation (T
A
= +70°C)
SO (derate 5.88mW/°C above +70°C) .......................471mW
Operating Temperature Range
MAX89_LESA .................................................-40°C to +85°C
Storage Temperature Range ...............................-65°C to+150°C
Lead Temperature (soldering, 10sec) ..............................+300°C
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
(V
IN
= 3V,
T
A
= 0°C to +85°C,
unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
CONDITION
MIN
TYP
MAX
UNITS
Operating Voltage
Quiescent Current
2.7
5.5
V
V
IN
= 5V, ONA = ONB = GND, I
OUT A
= I
OUT B
= 0
18
30
m
A
Off-Supply Current
0.03
1
m
A
ONA = ONB = IN, V
IN
= V
OUT A
= V
OUT B
= 5.5V
m
A
Off-Switch Current
ONA = ONB = IN, V
IN
= 5.5V, V
OUT A
= V
OUT B
= 0
Rising edge, 1% hysteresis
0.04
3
Undervoltage Lockout
2.0
2.4
2.6
V
MAX894L
120
225
V
IN
= 4.5V
MAX895L
250
420
On-Resistance
m
½
MAX894L
MAX895L
150
300
V
IN
= 3.0V
300
500
Current-Limit-Amplifier Threshold
V
SET
required to turn the switch off (Note 1)
1.178
1.240
1.302
V
MAX894L
500
Maximum Output Current
mA
MAX895L
250
MAX894L, I
OUT
= 250mA
945
1085
1270
I
OUT
to I
SET
Current Ratio
V
OUT
= 1.6V to 2.8V
A/A
MAX895L, I
OUT
= 125mA
910
1050
1235
ONA, ONB Input Low Voltage
V
IN
= 2.7V to 5.5V
0.8
V
V
IN
= 2.7V to 3.6V
2.0
V
ONA, ONB Input High Voltage
V
IN
= 4.5V to 5.5V
2.4
0.01
1
m
A
ONA, ONB Input Leakage
V
ONA
= V
ONB
= 5.5V
V
SET A
= 1.24V, ONA = 0, ONB = V
IN
, I
OUT A
= 0
0.5
3
m
A
I
SETA,
I
SETB
Bias Current
V
SET B
= 1.24V, ONB = 0, ONA = V
IN
, I
OUT B
= 0
0.5
3
m
s
Slow-Current-Loop Response Time
20% current overdrive, V
CC
= 5V
5
Fast-Current-Loop Response Time
2
m
s
V
IN
= 5V, I
OUT
= 250mA (MAX894L), 125mA (MAX895L)
100
200
Turn-On Time
m
s
V
IN
= 3V, I
OUT
= 250mA (MAX894L), 125mA (MAX895L)
150
Turn-Off Time
0.8
1.2
20
m
s
Note 1:
Tested with I
OUT
= 50mA for the MAX894L and 25mA for the MAX895L, and V
SET
raised until V
IN
- V
OUT
³
0.8V.
2
_______________________________________________________________________________________
Dual, Current-Limited, High-Side P-Channel
Switches with Thermal Shutdown
ELECTRICAL CHARACTERISTICS
(Note 2)
(V
IN
= 3V,
T
A
= -40°C to +85°C,
unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
CONDITION
MIN
TYP
MAX
UNITS
Operating Voltage
Quiescent Current
3.0
5.5
V
m
A
V
IN
= 5V, ONA = ONB = GND, I
OUT A
= I
OUT B
= 0
50
A
Off-Supply Current
ONA = ONB = IN, V
IN
= V
OUT A
= V
OUT B
= 5.5V
2.2
m
Off-Switch Current
ONA = ONB = IN, V
IN
= 5.5V, V
OUT A
= V
OUT B
= 0
Rising edge, 1% hysteresis
MAX894L
8
m
A
Undervoltage Lockout
2.0
2.9
V
250
V
IN
= 4.5V
MAX895L
420
m
On-Resistance
W
MAX894L
MAX895L
300
V
IN
= 3.0V
500
Current-Limit-Amplifier Threshold
V
SET_
required to turn the switch off (Note 1)
1.14
1.34
V
MAX894L, I
OUT
= 250mA
910
1360
V
SET
= 1.24V,
V
OUT
= 1.6V to 2.8V
I
OUT
to I
SET
Current Ratio
A/A
MAX895L, I
OUT
= 125mA
880
1315
m
s
Turn-On Time
V
IN
= 5V
200
m
s
Turn-Off Time
0.25
20
Note 2:
Specifications to -40°C are guaranteed by design, not production tested.
_______________________________________________________________________________________
3
Dual, Current-Limited, High-Side P-Channel
Switches with Thermal Shutdown
__________________________________________Typical Operating Characteristics
(Typical Operating Circuit, T
A
= +25°C, unless otherwise noted.)
QUIESCENT CURRENT
vs. TEMPERATURE
QUIESCENT CURRENT
vs. INPUT VOLTAGE
OFF-SUPPLY CURRENT
vs. TEMPERATURE
28
24
0.07
ONA = ONB = GND
I
OUT A
= I
OUT B
= 0
24
0.06
22
20
0.05
20
16
0.04
V
IN
= 5V
18
12
0.03
16
V
IN
= 3V
8
0.02
14
4
0.01
12
0
0
0
1
2
3
4
5
6
-40
-20
0 0
40
60
80
100
-40
-20
0 0 0
60
80
100
TEMPERATURE (°C)
INPUT VOLTAGE (V)
TEMPERATURE (°C)
OFF-SWITCH CURRENT
vs. TEMPERATURE
NORMALIZED ON-RESISTANCE
vs. TEMPERATURE
I
OUT
/I
SET
vs. I
LIMIT
1600
0.07
1.3
I
OUT
= 1/2 I
LIMIT
1400
0.06
1.2
1200
0.05
1.1
1000
0.04
1.0
800
0.03
0.9
600
0.02
0.8
400
0.01
200
0.7
0
0
0.6
0
20
40
60
80
100
120
140
-40
-20
0 0 0
60
80
100
-40
-20
0 0 0
60
80
100
I
LIMIT
(%)
TEMPERATURE (°C)
TEMPERATURE (°C)
NORMALIZED OUTPUT CURRENT
vs. OUTPUT VOLTAGE
TURN-ON TIME
vs. TEMPERATURE
TURN-OFF TIME
vs. TEMPERATURE
7
1.4
260
I
LOAD
=
I
LIMIT
I
LOAD
=
I
LIMIT
V
IN
= 5V
240
6
1.2
220
I
LIMIT
V
IN
= 5V
1.0
5
200
180
0.8
4
V
IN
= 3V
160
0.6
3
V
IN
= 3V
140
120
0.4
2
100
V
IN
= 5V
0.2
1
80
0
60
0
0
1
2
3
4
5
6
-40
-20
0 0 0
60
80
100
-40
-20
0 0 0
60
80
100
OUTPUT VOLTAGE (V)
TEMPERATURE (°C)
TEMPERATURE (°C)
4
_______________________________________________________________________________________
Dual, Current-Limited, High-Side P-Channel
Switches with Thermal Shutdown
____________________________Typical Operating Characteristics (continued)
(Typical Operating Circuit, T
A
= +25°C, unless otherwise noted.)
CURRENT-LIMIT RESPONSE
(MAX894L, R
L
= 0.7
CURRENT-LIMIT RESPONSE
(MAX894L, R
L
= 1
W
)
W
)
5V
A
5V
A
B
B
0A
C
0A
0V
C
0V
MAX894/895/896 TOC-10
MAX894/895/896 TOC-9
1
m
s/div
2
m
s/div
C
IN
= 47
F
A: V
IN,
500mV/div, AC coupled
F, C
OUT
= 0.1
B: I
OUT,
2A/div
C: V
OUT,
5V/div
m
m
C
IN
= 47
F
A: V
IN,
500mV/div, AC coupled
m
F, C
OUT
= 0.1
m
B: I
OUT,
2A/div
C: V
OUT,
5V/div
LOAD-TRANSIENT RESPONSE
(MAX894L)
A
0A
B
0V
MAX494/495/496 TOC-13
2ms/div
V
IN
= 5V
A: I
OUT
= 0 to 500mA, 0.2A/div
B: V
OUT
RIPPLE, 200mV/div, AC COUPLED
SWITCH TURN-ON TIME
SWITCH TURN-OFF TIME
A
A
0V
B
B
0V
MAX894/895/896 TOC-11
MAX894/895/896 TOC-12
20µs/div
2µs/div
V
IN
= 5V, I
OUT
= I
LIMIT
A: V
ON
, 2V/div
B: V
OUT
, 2V/div
V
IN
= 5V, I
OUT
= I
LIMIT
A: V
ON
, 2V/div
B: V
OUT
, 2V/div
_______________________________________________________________________________________
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