MAX9919

Manufacturer Part NumberMAX9919
DescriptionThe MAX9918/MAX9919/MAX9920 are single-supply, high-accuracy current-sense amplifiers with a high input common-mode range that extends from -20V to +75V
ManufacturerMaxim
MAX9919 datasheet
 


1
Page 1
2
Page 2
3
Page 3
4
Page 4
5
Page 5
6
Page 6
7
Page 7
8
Page 8
9
Page 9
10
Page 10
11
12
13
14
15
16
17
18
Page 1/18

Download datasheet (3Mb)Embed
Next
19-5015; Rev 4; 7/11
-20V to +75V Input Range, Precision
Uni-/Bidirectional, Current-Sense Amplifiers
General Description
The MAX9918/MAX9919/MAX9920 are single-supply,
high-accuracy current-sense amplifiers with a high
input common-mode range that extends from -20V to
+75V. These amplifiers are well suited for current moni-
toring of inductive loads such as motors and solenoids,
where common-mode voltages can become negative
due to inductive kickback, reverse-battery conditions,
or transient events.
The MAX9918/MAX9920 feature adjustable gain set by
an external resistive-divider network. The MAX9919 fea-
tures fixed gains of 45V/V (MAX9919F) and 90V/V
(MAX9919N). The MAX9918/MAX9919/MAX9920 oper-
ate as unidirectional amplifiers when V
and as bidirectional amplifiers when V
The MAX9920 attenuates the input signal by a factor of
4 at the input level-shifting stage allowing the device to
sense voltages up to 200mV (unidirectional operation)
or ±100mV (bidirectional operation).
The MAX9918/MAX9919/MAX9920 operate with a sin-
gle 5V supply voltage, are fully specified over the -40°C
to +125°C automotive temperature range, and are
available in an 8-pin SOIC package.
H-Bridge Motor Current Sensing
Solenoid Current Sensing
Current Monitoring of Inductive Loads
High- and Low-Side Precision Current Sensing
4x4 Transmission Control
Electronic Throttle Control
Super-Capacitor Charge/Discharge Monitoring in
Hybrid Cars
Precision High-Voltage Current Monitoring
V
BATT
φ1A
R
SENSE
M
φ2B
________________________________________________________________ Maxim Integrated Products
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.
o -20V to +75V Input Common-Mode Voltage Range
o 400µV (max) Input Offset Voltage
o 0.6% (max) Gain Accuracy Error
o Uni- or Bidirectional Current Sensing
o Reference Input for Bidirectional OUT
o 120kHz, -3dB Bandwidth (MAX9919N)
o Single-Supply Operation (4.5V to 5.5V)
o 1mA Supply Current
o 0.5µA (typ) Shutdown Current
o Rail-to-Rail Output
= GND
REFIN
o -40°C to +125°C Automotive Temperature Range
= V
/2.
REFIN
CC
PART
MAX9918ASA+
MAX9918ASA/V+
Applications
MAX9919FASA+
MAX9919NASA+
MAX9919NASA/V+
MAX9920ASA+
MAX9920ASA/V+
Note: All devices operate over the -40°C to +125°C temperature
range.
+ Denotes a lead(Pb)-free/RoHS-compliant package.
/V denotes an automotive qualified part.
* EP = Exposed pad.
V
CC
φ2B
MAX9918
MAX9920
RS+
INPUT STAGE
LEVEL SHIFTER
RS-
ADJUSTABLE GAIN
φ1B
SHDN
GND
Features
Ordering Information/
Selector Guide
V
GAIN
PIN-
SENSE
(mV)
(V/V)
PACKAGE
±50
Adjustable
8 SOIC-EP*
±50
Adjustable
8 SOIC-EP*
±50
45
8 SOIC-EP*
±50
90
8 SOIC-EP*
±50
90
8 SOIC-EP*
±200
Adjustable
8 SOIC-EP*
±200
Adjustable
8 SOIC-EP*
Typical Operating Circuit
V
CC
OUT
A
ADC
R2
FB
R1
REFIN
REF
μC
GND
1

MAX9919 Summary of contents

  • Page 1

    ... The MAX9918/MAX9920 feature adjustable gain set by an external resistive-divider network. The MAX9919 fea- tures fixed gains of 45V/V (MAX9919F) and 90V/V (MAX9919N). The MAX9918/MAX9919/MAX9920 oper- ate as unidirectional amplifiers when V and as bidirectional amplifiers when V The MAX9920 attenuates the input signal by a factor of ...

  • Page 2

    ... CC RS+, RS- to GND (V = 0V) .............-15V to +80V (15 minutes) CC Differential Input Voltage ( RS+ RS- (MAX9918/MAX9919).................................±15V (Continuous) Differential Input Voltage ( (MAX9920) .............................±5V (Continuous) RS+ RS- REFIN, FB, OUT to GND.............................-0. SHDN to GND.........................................................-0.3V to +20V ** As per JEDEC51 Standard (multilayer board). PACKAGE THERMAL CHARACTERISTICS (Note 1) SOIC-EP Junction-to-Ambient Thermal Resistance (θ ...

  • Page 3

    ... V ≤ +75V SHDN +14V, +75V, V RS+ RS- Common mode MAX9918, MAX9919_ Differential Common mode MAX9920 Differential MAX9918, MAX9919_ Inferred from gain SENSE error test MAX9920 MAX9918, MAX9920 G MAX9919F MAX9919N MAX9918 G ADJ MAX9920 = V / 100kΩ; for MAX9918, A REFIN ...

  • Page 4

    ... GND L MAX9918, MAX9919_ 400mV for SENSE R = 10kΩ to GND L MAX9920 V = -200mV for SENSE R = 100kΩ MAX9918, MAX9919_ -400mV for SENSE R = 10kΩ MAX9920 OUT shorted OUT shorted to GND R OUT M AX 9918, M AX9919_ Inferred from REFIN ...

  • Page 5

    ... M AX 9918 9919_ REFIN MAX9920 ±200mV RS+ RS ≤ V ≤ V SHDN CC V Inferred from PSRR test CC MAX9918, MAX9919_ 4.5V ≤ V PSRR 4.5V ≤ V MAX9920 T = +25° +14V RS+ RS 40° 125° +25° -2V ...

  • Page 6

    ... Measurements are made MAX9918/MAX9919N/MAX9919F, and V Note 3: Extrapolated V as described above in Note 2 is used to calculate V OS Note 4: OUT should be 100mV away from either rail to achieve rated accuracy, or limited MAX9918/MAX9919N/MAX9919F and 200mV for the MAX9920. Note 5: Not production tested. Guaranteed by design. 6 _______________________________________________________________________________________ = ( 0V, V ...

  • Page 7

    ... RS+ 0.35 0.30 0.25 0.20 0.15 0.10 0.05 0 -400 -320 -240 -160 - 160 240 320 400 OFFSET VOLTAGE (FV 125 100 14V -25 - -2V CM MAX9918ASA - REF GND -100 4.5 4.6 4.7 4.8 4.9 5.0 5.1 5.2 5.3 5.4 5.5 V (V) CC GAIN ERROR (V = -2V, MAX9919F +45V/V) RS+ V 0.6 0.5 0.4 0.3 0.2 0.1 0 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 GAIN ERROR (%) 7 ...

  • Page 8

    ... Input Range, Precision Uni-/Bidirectional, Current-Sense Amplifiers ( +25°C, unless otherwise noted GAIN ERROR (V = -2V, MAX9919N, A RS+ 0.6 0.5 0.4 0.3 0.2 0.1 0 -0.4 -0.3 -0.2 -0.1 GAIN ERROR (%) GAIN ERROR vs. V 0.5 0.4 0.3 0 -0.1 -0.2 -0.3 V -0.4 -0.5 4.5 4.7 4 LINEARITY vs. V 0.10 0.08 0.06 0. +25° -40° 0.02 0 -0. +125°C A -0.04 -0.06 -0.08 -0.10 -30 -20 -10 ...

  • Page 9

    Input Range, Precision Uni-/Bidirectional, Current-Sense Amplifiers ( +25°C, unless otherwise noted LINEARITY vs +14V 0.14 REFIN GND ...

  • Page 10

    Input Range, Precision Uni-/Bidirectional, Current-Sense Amplifiers ( +25°C, unless otherwise noted vs 1.0 0.9 0 -2V 0.7 CM 0.6 0 14V CM 0.4 ...

  • Page 11

    Input Range, Precision Uni-/Bidirectional, Current-Sense Amplifiers ( +25°C, unless otherwise noted SMALL-SIGNAL TRANSIENT (GAIN = 45V/V) 5mV/div MAX9918, V 50mV/div V = 10mV TO 15mV SENSE 10Fs/div LARGE-SIGNAL TRANSIENT (GAIN = ...

  • Page 12

    Input Range, Precision Uni-/Bidirectional, Current-Sense Amplifiers ( +25°C, unless otherwise noted SHUTDOWN ON/OFF DELAY 5V/div 1V/div OUTPUT OVERDRIVE RECOVERY (30V/V) 200mV/div 2V/div 12 ______________________________________________________________________________________ Typical Operating Characteristics (continued) MAX9918 toc37 5V/div ...

  • Page 13

    ... MAX9918/MAX9920. The MAX9919 is a fixed gain device available with laser-trimmed resistors for gains of 45V/V (MAX9919F) and 90V/V (MAX9919N). The MAX9918/MAX9919 operate with a full-scale sense voltage of 50mV. The input stage of the MAX9920 pro- vides an attenuation factor of 4, enabling a full-scale sense voltage of 200mV. ...

  • Page 14

    ... SENSE RS+ RS- MAX9919N SHDN GND Figure 2. Bidirectional Operation 14 ______________________________________________________________________________________ The MAX9918/MAX9919 operate in bidirectional mode by application of a low-source impedance reference voltage in the REFIN. For the MAX9920, the reference voltage range = V . The REFIN GND relative to V OUT ±V ...

  • Page 15

    ... SENSE the MAX9918/MAX9919, or 200mV for the MAX9920 and G is the gain of the device externally adjustable for the MAX9918/MAX9920. The MAX9919 has a fixed gain version of 45V/V (MAX9919F) or 90V/V (MAX9919N). In unidirectional applications (V REFIN gain of the MAX9918/MAX9920 to utilize the full output range between GND and V ...

  • Page 16

    ... SENSE RS- I LOAD RS+ MAX9918 50mV (typ) R SENSE RS- MAX9920 200mV (typ) I LOAD 16 ______________________________________________________________________________________ V CC MAX9919F A INPUT INPUT STAGE/ LEVEL SHIFTER SHDN GND V CC MAX9918 MAX9920 INPUT INPUT STAGE/ LEVEL SHIFTER SHDN GND GAIN IS SET BY EXTERNAL RESISTORS, R1 AND [1+(R2/R1)] FOR MAX9918 G = [1+(R2/R1)]/4 FOR MAX9920 ...

  • Page 17

    ... Uni-/Bidirectional, Current-Sense Amplifiers For the latest package outline information and land patterns (footprints www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing per- tains to the package regardless of RoHS status ...

  • Page 18

    ... Added automotive qualified parts for the MAX9919NASA/V+ and the MAX9920ASA/V+ 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. ...