MAX9938:1µA, 4-Bump UCSP/SOT23, Precision Current-Sense Amplifier

Industry's Smallest Current-Sense Amplifier: 1mm x 1mm with ICC < 1µA, VOS < 500µV, Gain Error < 0.5%

The MAX9938 high-side current-sense amplifier offers precision accuracy specifications of VOS less than 500µV (max) and gain error less than 0.5% (max). Quiescent supply current is an ultra-low 1µA. The MAX9938 fits in a tiny, 1mm x 1mm UCSP™ package size or a 5-pin SOT23 package, making the part ideal for applications in notebook computers, cell phones, PDAs, and all battery-operated portable devices where accuracy, low quiescent current, and small size are critical. The MAX9938 features an input common-mode voltage range from 1.6V to 28V. These current-sense amplifiers have a voltage output and are offered in four gain versions: 25V/V (MAX9938T), 50V/V (MAX9938F), 100V/V (MAX9938H), and 200V/V (MAX9938W). The four gain selections offer flexibility in the choice of the external current-sense resistor. The very low 500µV (max) input offset voltage allows small 25mV to 50mV full-scale VSENSE voltage for very low voltage drop at full-current measurement. The MAX9938 is offered in tiny 4-bump, UCSP (1mm x 1mm x 0.6mm footprint), 5-pin SOT23, and 6-pin µDFN (2mm x 2mm x 0.8mm) packages specified for operation over the -40°C to +85°C extended temperature range.

Key Features
  • Ultra-Low Supply Current of 1µA (max)
  • Low 500µV (max) Input Offset Voltage
  • Low < 0.5% (max) Gain Error
  • Input Common Mode: +1.6V to +28V
  • Voltage Output
  • Four Gain Versions Available
    • +25V/V (MAX9938T)
    • 50V/V (MAX9938F)
    • 100V/V (MAX9938H)
    • 200V/V (MAX9938W)
  • Tiny 1mm x 1mm x 0.6mm, 4-Bump UCSP, 5-Pin SOT23, or 2mm x 2mm x 0.8mm, 6-Pin µDFN Packages
MAX9938: Typical Operating Circuit
MAX9938: Typical Operating Circuit
Applications/Uses
  • Cell Phones
  • Notebook Computers
  • PDAs
  • Portable/Battery-Powered Systems
  • Power Management Systems
DataSheet
titleDownload file
MAX9938 Data SheetMAX9938.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
MAX9938Voltage1.6281.6281No25
50
100
50025 V/V
50 V/V
100 V/V
200 V/V
0.530
60
125
0-40 to +85µDFN/6
SOT/5
UCSP/4
$0.65 @1k
Design kits & evaluation modules
Related Products
  • MAX4073:Low-Cost, SC70, Voltage-Output, High-Side Current-Sense Amplifier
  • MAX4372:Low-Cost, UCSP/SOT23, Micropower, High-Side Current-Sense Amplifier with Voltage Output
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX9938FEBS+G45ActiveUCSP,;4 pin;1.1 mm²-40°C to +85°CLead Free
MAX9938FEBS+TActiveUCSP,;4 pin;1.1 mm²-40°C to +85°CLead Free
MAX9938FEBS+TG45ActiveUCSP,;4 pin;1.1 mm²-40°C to +85°CLead Free
MAX9938FELT+ActiveµDFN,;6 pin;4.2 mm²-40°C to +85°CLead Free
MAX9938FELT+TActiveµDFN,;6 pin;4.2 mm²-40°C to +85°CLead Free
MAX9938FEUK+ActiveSOT,;5 pin;9 mm²-40°C to +85°CLead Free
MAX9938FEUK+TActiveSOT,;5 pin;9 mm²-40°C to +85°CLead Free
MAX9938HEBS+TNo Longer AvailableUCSP,;4 pin;1.1 mm²-40°C to +85°CLead Free
MAX9938HEBS+TG45ActiveUCSP,;4 pin;1.1 mm²-40°C to +85°CLead Free
MAX9938HEUK+ActiveSOT,;5 pin;9 mm²-40°C to +85°CLead Free
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX9938HEUK+TActiveSOT,;5 pin;9 mm²-40°C to +85°CLead Free
MAX9938TEBS+TActiveUCSP,;4 pin;1.1 mm²-40°C to +85°CLead Free
MAX9938TEBS+TG45ActiveUCSP,;4 pin;1.1 mm²-40°C to +85°CLead Free
MAX9938TEUK+ActiveSOT,;5 pin;9 mm²-40°C to +85°CLead Free
MAX9938TEUK+TActiveSOT,;5 pin;9 mm²-40°C to +85°CLead Free
MAX9938WEBS+ActiveUCSP,;4 pin;1.1 mm²-40°C to +85°CLead Free
MAX9938WEBS+TActiveUCSP,;4 pin;1.1 mm²-40°C to +85°CLead Free
MAX9938WEBS+TG45ActiveUCSP,;4 pin;1.1 mm²-40°C to +85°CLead Free
MAX9938WEUK+ActiveSOT,;5 pin;9 mm²-40°C to +85°CLead Free
MAX9938WEUK+TActiveSOT,;5 pin;9 mm²-40°C to +85°CLead Free
MAX9938.pdf MAX9938
Protect Current-Sense Amplifiers from Negative Overvoltage MAX9938