LT1970 - 500mA Power Op Amp with Adjustable Precision Current Limit

The circuit operates with single or split power supplies from 5V to 36V total supply voltage. In normal operation, the input stage supplies and the output stage supplies are connected (VCC to V+ and VEE to V–). To reduce power dissipation it is possible to power the output stage (V+, V–) from independent, lower voltage rails. The amplifier is unity-gain stable with a 3.6MHz gain bandwidth product and slews at 1.6V/µs. The current limit circuits operate with a 2MHz response between the VCSRC or VCSNK control inputs and the amplifier output.

Open collector status flags signal current limit circuit activation, as well as thermal shutdown of the amplifier. An enable logic input puts the amplifier into a low power, high impedance output state when pulled low. Thermal shutdown and a ±800mA fixed current limit protect the chip under fault conditions.

The LT1970 is packaged in a 20-lead TSSOP package with a thermally conductive copper bottom plate to facilitate heat sinking.

Features

±500mA Minimum Output Current
Independent Adjustment of Source and Sink Current Limits
2% Current Limit Accuracy
Operates with Single or Split Supplies
Shutdown/Enable Control Input
Open Collector Status Flags: Sink Current Limit Source Current Limit Thermal Shutdown
Fail Safe Current Limit and Thermal Shutdown
1.6V/µs Slew Rate
3.6MHz Gain Bandwidth Product
Fast Current Limit Response: 2MHz Bandwidth
Specified Temperature Range: –40°C to 85°C