INA1x8 High-Side Measurement Current Shunt Monitor
1 Features
- Complete Unipolar High-Side Current Measurement Circuit
- Wide Supply and Common-Mode Range
- INA138: 2.7 V to 36 V
- INA168: 2.7 V to 60 V
- Independent Supply and Input Common-Mode Voltages
- Single Resistor Gain Set
- Low Quiescent Current (25 µA Typical)
- Wide Temperature Range: –40°C to +125°C
- 5-Pin SOT-23 Package
2 Applications
- Current Shunt Measurement:
- Telephone, Computers
- Portable and Battery-Backup Systems
- Battery Chargers
- Power Management
- Cell Phones
- Precision Current Source
3 Description
The INA138 and INA168 (INA1x8) are high-side, unipolar, current shunt monitors. Wide input common-mode voltage range, low quiescent current, and tiny SOT-23 packaging enable use in a variety of applications.
Input common-mode and power-supply voltages are independent and can range from 2.7 V to 36 V for the INA138 and 2.7 V to 60 V for the INA168. Quiescent current is only 25 µA, which permits connecting the power supply to either side of the current measurement shunt with minimal error.
The device converts a differential input voltage to a current output. This current is converted back to a voltage with an external load resistor that sets any gain from 1 to over 100. Although designed for current shunt measurement, the circuit invites creative applications in measurement and level shifting.
Both the INA138 and INA168 are available in SOT23-5 and are specified for the –40°C to 125°C temperature range.
Device Information(1)
| PART NUMBER | PACKAGE | BODY SIZE (NOM) |
|---|---|---|
| INA138 | SOT-23 (5) | 2.90 mm × 1.60 mm |
| INA168 |
- For all available packages, see the package option addendum at the end of the datasheet.
Typical Application Circuit
4 Revision History
Changes from D Revision (December 2014) to E Revision
- Added reference design link to navigation bar at the top of the front pageGo
- Changed body size from 18.00 mm × 18.00 mm to 2.90 mm × 1.60 mm in Device Information tableGo
- Changed pin numbers in pin functions table to match pin configuration figureGo
- Changed Absolute Maximum Ratings table for clarity; no values were changed Go
- Changed Recommended Operating Conditions table; moved some content from Electrical Characteristics table, but no values changedGo
- Changed all values in Thermal Information tableGo
- Changed Electrical Characteristics table; reformatted for clarity; moved some content to Recommended Operating Conditions table, and deleted duplicate contentGo
- Changed common-mode rejection test conditions to better highlight each device in Electrical Characteristics table Go
- Changed offset voltage vs temperature to offset voltage drift in Electrical Characteristics tableGo
- Changed offset voltage vs power supply test conditions to better highlight each device in Electrical Characteristics tableGo
- Changed reference in text from Figure 10 to Figure 11 in last paragraph of Selecting the Shunt Resistor and RL sectionGo
Changes from C Revision (November 2005) to D Revision
- Added ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information section. Go
