Precision, High-Side
Current-Sense Amplifiers
MAX471/MAX472
ABSOLUTE MAXIMUM RATINGS
Supply Voltage, RS+, RS-, V
CC
to GND....................-0.3V, +40V
RMS Current, RS+ to RS- (MAX471 only)..........................±3.3A
Peak Current, (RS+ to RS-) ......................................see Figure 5
Differential Input Voltage, RG1 to RG2 (MAX472 only) .....±0.3V
Voltage at Any Pin Except SIGN
MAX471 only ...........................................-0.3V to (RS+ - 0.3V)
MAX472 only ..........................................-0.3V to (V
CC
+ 0.3V)
Voltage at SIGN......................................................-0.3V to +40V
Current into SHDN, GND, OUT, RG1, RG2, V
CC
................±50mA
Current into SIGN.................................................+10mA, -50mA
Continuous Power Dissipation (T
A
= +70°C)
MAX471 (Note 1):
Plastic DIP (derate 17.5mW/°C above +70°C) ..................1.4W
SO (derate 9.9mW/°C above +70°C) .............................791mW
MAX472 :
Plastic DIP (derate 9.09mW/°C above +70°C) ..............727mW
SO (derate 5.88mW/°C above +70°C) ...........................471mW
Operating Temperature Ranges
MAX47_C_A ........................................................0°C to +70°C
MAX47_E_A .....................................................-40°C to +85°C
Junction Temperature Range ............................-60°C to +150°C
Storage Temperature Range .............................-60°C to +160°C
Lead Temperature (soldering, 10sec) .............................+300°C
Note 1:
Due to special packaging considerations, MAX471 (DIP, SO) has a higher power dissipation rating than the MAX472. RS+
and RS- must be soldered to large copper traces to achieve this dissipation rating.
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—MAX471
(RS+ = +3V to +36V, T
A
= T
MIN
to T
MAX
, unless otherwise noted. Typical values are at T
A
= +25°C.)
PARAMETER
Supply Voltage
Supply Current
Sense Current
Sense Resistor
Current-Sense Ratio
No-Load OUT Error
Low-Level OUT Error
Power-Supply Rejection Ratio
SIGN Threshold (I
LOAD
required
to switch SIGN)
SIGN Output Leakage Current
SIGN Sink Current
Shutdown Supply Current
SHDN Input Low Voltage
SHDN Input Low Current
SHDN Input High Voltage
SHDN Input High Current
OUT Output Voltage Range
OUT Output Resistance
OUT Rise, Fall Time
OUT Settling Time to 1%
of Final Value
2
I
OL
V
IL
I
IL
V
IH
I
IH
V
OUT
R
OUT
t
R
, t
F
t
s
I
LOAD
= 3.0A, V
OUT
= 0V to (V
RS+
- 1.5V)
I
LOAD
= 50mA to 3.0A, R
OUT
= 2kΩ,
C
OUT
= 50pF, 10% to 90%
I
LOAD
= 100mA to 3.0A, R
OUT
= 2kΩ,
C
OUT
= 50pF
V
SHDN
= 2.4V
0
1
3
4
15
V
SHDN
= 0V
2.4
1.0
V
RS+
- 1.5
PSRR
SYMBOL
V
RS+
I
RS+
I
LOAD
R
SENSE
I
OUT
/
I
LOAD
I
LOAD
= 1A,
RS+ = 10V
I
LOAD
= 0A,
RS+ = 10V
I
LOAD
= 30mA,
RS+ = 10V
MAX471C
MAX471E
V
SIGN =
36V
V
SIGN
= 0.3V
0.1
1.5
18.0
0.3
1.0
I
RS+(SHDN)
V
SHDN
= 2.4V; V
CC
= 3V to 20V
MAX471C
MAX471E
MAX471C
MAX471E
MAX471C
MAX471E
3V
≤
RS+
≤
36V, I
LOAD
= 1A
0.490
0.4875
35
0.500
0.500
I
LOAD
= 0A, excludes I
SIGN
CONDITIONS
MIN
3
50
TYP
MAX
36
113
±3
70
0.510
0.5125
2.5
3.0
±2.5
±3.0
0.1
±6.0
±7.0
1.0
UNITS
V
µA
A
RMS
mΩ
mA/A
µA
µA
%/V
mA
µA
mA
µA
V
µA
V
µA
V
MΩ
µs
µs
±4.0
_______________________________________________________________________________________
MAXIM [ MAXIM INTEGRATED PRODUCTS ]
