19-1146; Rev 4; 4/11
1.2A, Current-Limited, High-Side
P-Channel Switch with Thermal Shutdown
General Description
The MAX890L smart, low-voltage, P-channel, MOSFET
power switch is intended for high-side load-switching
applications. This switch operates with inputs from
+2.7V to +5.5V, making it ideal for both +3V and +5V
systems. Internal current-limiting circuitry protects the
input supply against overload. Thermal-overload pro-
tection limits power dissipation and junction tempera-
tures.
The MAX890L’s maximum current limit is 1.2A. The cur-
rent limit through the switch is programmed with a
resistor from SET to ground. The quiescent supply cur-
rent is a low 10µA. When the switch is off, the supply
current decreases to 0.1µA.
The MAX890L is available in an 8-pin SO package.
♦
+2.7V to +5.5V Input Range
♦
Programmable Current Limit
♦
Low Quiescent Current
10µA (typ) at V
IN
= +3.3V
0.1µA (typ) with Switch Off
♦
Thermal Shutdown
♦
FAULT
Indicator Output
♦
0.09Ω (typ) On-Resistance
Features
MAX890L
Applications
PCMCIA Slots
Access Bus Slots
Portable Equipment
PART
MAX890LC/D
MAX890LESA+
MAX890LESA/V+
Ordering Information
TEMP RANGE
0°C to +70°C
PIN-
PACKAGE
Dice**
CURRENT
LIMIT
1.2A
1.2A
1.2A
-40°C to +85°C 8 SO
-40°C to +85°C 8 SO
*To
order this unit in tape and reel, add (T) to the end of the
part number.
**Dice
are tested at T
A
= +25°C.
+Denotes
a lead(Pb)-free/RoHS-compliant package.
/V denotes an automotive qualified part.
Typical Operating Circuit
Pin Configuration
TOP VIEW
INPUT
IN
IN
100kΩ
FAULT
1μF
GND
ON
SET
R
SET
ON/OFF
ON
3
GND
4
OUT
OUTPUT
0.1μF
+
IN
1
IN
2
8
FAULT
MAX890L
OUT
MAX890L
7
OUT
6
OUT
5
SET
SO
________________________________________________________________
Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,
or visit Maxim’s website at www.maxim-ic.com.
1.2A, Current-Limited, High-Side
P-Channel Switch with Thermal Shutdown
MAX890L
ABSOLUTE MAXIMUM RATINGS
IN to GND ................................................................-0.3V to +6V
ON, FAULT
to GND .................................................-0.3V to +6V
SET, OUT to GND ...................................... -0.3V to (V
IN
+ 0.3V)
Maximum Continuous Switch Current ..................................1.5A
Continuous Power Dissipation (T
A
= +70°C)
SO (derate 5.88mW/°C above +70°C) ..........................471mW
Operating Temperature Range
MAX890LESA ....................................................-40°C to +85°C
Storage Temperature Range ........................... -65°C to +150°C
Lead Temperature (soldering, 10s) . ...............................+300°C
Soldering Temperature (reflow) .......................................+260°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
Operating Voltage
Quiescent Current
Off-Supply Current
Off-Switch Current
Undervoltage Lockout
On-Resistance
Current-Limit-Amplifier Threshold
Maximum Output Current Limit
I
OUT
to I
SET
Current Ratio
ON
Input Low Voltage
ON
Input High Voltage
ON
Input Leakage Current
I
SET
Bias Current
FAULT
Logic Output Low Voltage
FAULT
Logic Output High Leakage Current
Slow-Current-Loop Response Time
Fast-Current-Loop Response Time
Turn-On Time
Turn-Off Time
V
IN
= 5V, I
OUT
= 500mA
V
IN
= 3V, I
OUT
= 500mA
V
IN
= 5V
2
I
OUT
= 500mA, V
OUT
> 1.6V
V
IN
= 2.7V to 5.5V
V
IN
= 2.7V to 3.6V
V
IN
= 4.5V to 5.5V
V
ON
= 5.5V
V
SET
= 1.24V, I
OUT
= 0A; V
IN
= V
OUT
I
SINK
= 1mA, V
SET
= 1.4V
V
FAULT
= 5.5V, V
SET
= 1V
20% current overdrive, V
CC
= 5V
0.05
5
2
120
185
5
200
2.0
2.4
0.01
0.5
1
3
0.4
1
970
V
IN
= 5V,
ON
= GND, I
OUT
= 0A
ON
= IN, V
IN
= V
OUT
= 5.5V
ON
= IN, V
IN
= 5.5V, V
OUT
= 0V
Rising edge, 1% hysteresis
V
IN
= 4.5V
V
IN
= 3.0V
V
SET
required to turn the switch off (Note 1)
1.178
2.0
CONDITIONS
MIN
2.7
13
0.03
0.04
2.4
75
90
1.240
1.2
1110
1300
0.8
TYP
MAX
5.5
20
1
15
2.6
130
150
1.302
UNITS
V
µA
µA
µA
V
mΩ
V
A
A/A
V
V
µA
µA
V
µA
µs
µs
µs
µs
2
_______________________________________________________________________________________
1.2A, Current-Limited, High-Side
P-Channel Switch with Thermal Shutdown
ELECTRICAL CHARACTERISTICS
(V
IN
= +3V,
T
A
= -40°C to +85°C,
unless otherwise noted.) (Note 2)
PARAMETER
Operating Voltage
Quiescent Current
Off-Supply Current
Off-Switch Current
Undervoltage Lockout
On-Resistance
Current-Limit-Amplifier Threshold
I
OUT
to I
SET
Current Ratio
FAULT
Logic Output Low Voltage
Turn-On Time
Turn-Off Time
V
IN
= 5V,
ON
= GND, I
OUT
= 0A
ON
= IN, V
IN
= V
OUT
= 5.5V
ON
= IN, V
IN
= 5.5V, V
OUT
= 0V
Rising edge, 1% hysteresis
V
IN
= 4.5V
V
IN
= 3.0V
V
SET
required to turn the switch off (Note 1)
I
OUT
= 500mA, V
OUT
> 1.6V
I
SINK
= 1mA, V
SET
= 1.4V
V
IN
= 5V
V
IN
= 5V
1
1.14
925
2.0
CONDITIONS
MIN
3.0
TYP
MAX
5.5
50
2.2
15
2.9
130
150
1.34
1390
0.4
200
20
UNITS
V
µA
µA
µA
V
mΩ
V
A/A
V
µs
µs
MAX890L
Note 1:
Tested with I
OUT
= 100mA and V
SET
raised until V
IN
- V
OUT
≥
0.8V.
Note 2:
Specifications to -40°C are guaranteed by design; not production tested.
_______________________________________________________________________________________
3
1.2A, Current-Limited, High-Side
P-Channel Switch with Thermal Shutdown
MAX890L
__________________________________________Typical Operating Characteristics
(T
A
= +25°C, unless otherwise noted.)
QUIESCENT CURRENT
vs. INPUT VOLTAGE
MAX890 toc01
QUIESCENT CURRENT
vs. TEMPERATURE
MAX890 toc02
OFF-SUPPLY CURRENT
vs. TEMPERATURE
MAX890 toc03
14
12
10
8
6
4
2
0
0
1
2
3
4
5
6
INPUT VOLTAGE (V)
ON = GND
I
OUT
= 0A
14
13
QUIESCENT CURRENT (μA)
V
IN
= 5V
12
11
V
IN
= 3V
10
9
8
7
-40
-20
0
20
40
60
80
100
QUIESCENT CURRENT (μA)
OFF-SUPPLY CURRENT (nA)
10
1
0.1
0.01
100
-40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
TEMPERATURE (°C)
OFF-SWITCH CURRENT
vs. TEMPERATURE
MAX890 toc04
NORMALIZED ON-RESISTANCE
vs. TEMPERATURE
I
OUT
= 1/2I
LIMIT
1.2
NORMALIZED R
ON
1.1
1.0
0.9
0.8
MAX890 toc05
I
OUT
/I
SET
RATIO
vs. I
LIMIT
MAX890 toc06
1000
1.3
1400
1200
I
OUT
/I
SET
RATIO
1000
800
600
400
200
0
OFF-SWITCH CURRENT (nA)
100
10
1
0.1
0.7
0.01
-40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
0.6
-40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
0
20
40
60
80
100
120
140
I
LIMIT
(%)
NORMALIZED OUTPUT CURRENT
vs. OUTPUT VOLTAGE
MAX890 toc07
TURN-ON TIME
vs. TEMPERATURE
MAX890 toc08
TURN-OFF TIME
vs. TEMPERATURE
I
LOAD
= I
LIMIT
7
6
t
OFF
(μs)
5
4
3
V
IN
= 5V
2
1
0
V
IN
= 3V
V
IN
= 5V
MAX890 toc09
1.2
NORMALIZED OUTPUT CURRENT
1.0
0.8
0.6
0.4
0.2
V
IN
= 5V
0
0
1
2
3
4
5
6
OUTPUT VOLTAGE (V)
I
LIMIT
260
240
220
200
t
ON
(μs)
180
160
140
120
100
80
60
-40
-20
0
20
40
60
80
I
LOAD
= I
LIMIT
8
V
IN
= 3V
100
-40
-20
0
20
40
60
80
100
TEMPERATURE (°C)
TEMPERATURE (°C)
4
_______________________________________________________________________________________
1.2A, Current-Limited, High-Side
P-Channel Switch with Thermal Shutdown
____________________________Typical Operating Characteristics (continued)
(T
A
= +25°C, unless otherwise noted.)
OUTPUT OVERLOAD
(SLOW LOOP RESPONSE)
MAX890 toc10
MAX890L
OUTPUT SHORT-CIRCUIT
(FAST LOOP RESPONSE)
MAX890 toc11
A
5V
A
5V
B
B
0A
C
0V, 0A
2μs/div
C
IN
= 100μF, C
OUT
= 0.1μF
A: V
IN
, 1V/div, AC-COUPLED
B: I
OUT
, 1A/div
C: V
OUT
, 2V/div
C
0V
2μs/div
C
IN
= 100μF, C
OUT
= 0.1μF
A: V
IN
, 1V/div, AC-COUPLED
B: I
OUT
, 5A/div
C: V
OUT
, 2V/div
LOAD-TRANSIENT RESPONSE
MAX890 toc12
SWITCH TURN-ON TIME
MAX890 toc13
A
0A
A
0V
B
B
5ms/div
V
IN
= 5V
A: I
OUT
= 0mA TO 750mA,
0.5A/div
B: V
OUT
RIPPLE,
200mV/div, AC COUPLED
V
IN
= 5V, I
OUT
= I
LIMIT
A: V
ON
, 2V/div
B: V
OUT
, 2V/div
20μs/div
SWITCH TURN-OFF TIME
MAX890 toc14
A
0V
B
0V
2μs/div
V
IN
= 5V, I
OUT
= I
LIMIT
A: V
ON
, 2V/div
B: V
OUT
, 2V/div
_______________________________________________________________________________________
5
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