MAX9934:High-Precision, Low-Voltage, Current-Sense Amplifier with Current Output and Chip Select for Multiplexing

Chip Select Allows Users to Mux Multiple MAX9934s onto a Single ADC Input

The MAX9934 high-precision, low-voltage, high-side current-sense amplifier is ideal for both bidirectional (charge/discharge) and unidirectional current measurements in battery-powered portable and laptop devices. Input offset voltage (VOS) is a low 10µV (max) at +25°C across the -0.1V to 5.5V input common-mode voltage range, and is independent of VCC. Its precision input specification allows the use of very small sense-voltages (typically ±10mV full-scale) for minimally invasive current sensing. The output of the MAX9934 is a current proportional to input VSENSE and is available in either 25µA/mV or 5µA/mV gain options (GM) with gain accuracy better than 0.25% (max) at +25°C. A chip select (CS) allows multiplexing of several MAX9934 current outputs to a single microcontroller ADC channel (see the Typical Operating Circuit). CS is compatible with 1.8V and 3.3V logic systems. The MAX9934 is designed to operate from a 2.5V to 3.6V VCC supply, and draws just 120µA (typ) quiescent current. When powered down (VCC = 0V), RS+ and RS- draw less than 0.1nA (typ) leakage current to reduce battery load. The MAX9934 is robust and protected from input faults of up to ±6V input differential voltage between RS+ and RS-. The MAX9934 is specified for operation over the -40°C to +125°C temperature range and is available in 8-pin µMAX® or a 6-bump UCSP™ (1mm x 1.5mm x 0.6mm), making it ideal for space-sensitive applications.

Key Features
  • Input Offset Voltage: 10µV (max)
  • Gain Error Less than 0.25%
  • -0.1V to +5.5V Input Common-Mode Voltage Range
  • Chip Select Allows Multiplexing Several MAX9934 Current Monitors to One ADC
  • Current Output Allows ROUT Selection for Gain Flexibility
  • Single Supply Operation: 2.5V to 3.6V
  • Two Gain Options: GM of 25µA/mV (MAX9934T) and 5µA/mV (MAX9934F)
  • Bidirectional or Unidirectional Operation
  • Small, 6-Bump UCSP (1mm x 1.5mm x 0.6mm) and 8-Pin µMAX Packages
MAX9934: Typical Operating Circuit
MAX9934: Typical Operating Circuit
Applications/Uses
  • MP3 Players
  • Notebook PCs and Ultra-Mobile PCs
  • PDAs and Smartphones
  • Portable Current Monitoring
  • Sensor Instrumentation Amplifiers
DataSheet
titleDownload file
MAX9934 Data SheetMAX9934.pdf
Parametrics
Part NumberOutput FormatCMVR
(V)
CMVR
(V)
VCC
(V)
VCC
(V)
ICC
(µA)
Bi-Dir. Curr. SenseVSENSE_FS
(mV)
VOS @25°C
(µV)
GainGain Accuracy @25°C
(%)
BW
(kHz)
Comp-
arators
Oper. Temp.
(°C)
Package/PinsBudgetary
Price
minmaxminmaxtyprecomm.maxmax@ -3dBSee Notes
MAX9934Current-0.15.52.53.6120Yes5
25
105 µA/mV
25 µA/mV
0.251.5
5
0-40 to +125µMAX/8
UCSP/6
$1.06 @1k
Design kits & evaluation modules
Quality and Environmental Data
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX9934FART+ActiveUCSP,;6 pin;1.5 mm²-40°C to +125°CLead Free
MAX9934FART+TActiveUCSP,;6 pin;1.5 mm²-40°C to +125°CLead Free
MAX9934FART+TG0YActiveUCSP,;6 pin;1.5 mm²-40°C to +125°CLead Free
MAX9934FAUA+ActiveµMAX,;8 pin;15.6 mm²-40°C to +125°CLead Free
MAX9934FAUA+TActiveµMAX,;8 pin;15.6 mm²-40°C to +125°CLead Free
MAX9934TART+ActiveUCSP,;6 pin;1.5 mm²-40°C to +125°CLead Free
MAX9934TART+TActiveUCSP,;6 pin;1.5 mm²-40°C to +125°CLead Free
MAX9934TAUA+ActiveµMAX,;8 pin;15.6 mm²-40°C to +125°CLead Free
MAX9934TAUA+TActiveµMAX,;8 pin;15.6 mm²-40°C to +125°CLead Free
MAX9934.pdf MAX9934
MAX9934.pdf MAX9934
MAX9934.pdf MAX9934
Lord Kelvin’s Sensing Method Lives On in the Measurement Accuracy of Ultra-Precision Current-Shunt Monitors/Current-Sense Amplif MAX9934
MAX9934.pdf MAX9934
MAX9934.pdf MAX9934