LT1970 500mA Power Op Amp with Adjustable Precision Current Limit FeaTuresDescripTion n ± 500mA Minimum Output Current The LT®1970 is a ±500mA power op amp with precise n Independent Adjustment of Source and externally controlled current limiting. Separate control Sink Current Limits voltages program the sourcing and sinking current limit n 2% Current Limit Accuracy sense thresholds with 2% accuracy. Output current may n Operates with Single or Split Supplies be boosted by adding external power transistors. n Shutdown/Enable Control Input The circuit operates with single or split power supplies n Open Collector Status Flags: from 5V to 36V total supply voltage. In normal operation, Sink Current Limit the input stage supplies and the output stage supplies are Source Current Limit connected (VCC to V+ and VEE to V–). To reduce power Thermal Shutdown dissipation it is possible to power the output stage (V+, n Fail Safe Current Limit and Thermal Shutdown V–) from independent, lower voltage rails. The amplifier is n 1.6V/µs Slew Rate unity-gain stable with a 3.6MHz gain bandwidth product n 3.6MHz Gain Bandwidth Product and slews at 1.6V/µs. The current limit circuits operate n Fast Current Limit Response: 2MHz Bandwidth with a 2MHz response between the VC n SRC or VCSNK control Specified Temperature Range: –40°C to 85°C inputs and the amplifier output. n Available in a 20-Lead TSSOP Package Open collector status flags signal current limit circuit activation, as well as thermal shutdown of the amplifier. applicaTions An enable logic input puts the amplifier into a low power, n Automatic Test Equipment high impedance output state when pulled low. Thermal n Laboratory Power Supplies shutdown and a ±800mA fixed current limit protect the n Motor Drivers chip under fault conditions. n Thermoelectric Cooler Driver The LT1970 is packaged in a 20-lead TSSOP package with L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear a thermally conductive copper bottom plate to facilitate Technology Corporation. All other trademarks are the property of their respective owners. heat sinking. Typical applicaTionAV = 2 Amplifier with Adjustable ±500mA Full-ScaleCurrent Limited Sinewave Into 10 Ω LoadCurrent Limit and Fault Indication VLIMIT 0V TO 5V 15V 15V V 4V LIMIT 3k IOUT(LIMIT) = ±10 • R VCC CS 2V V+ENVC V 0V V LOAD IN +IN SRC VCSNK –2V ISNK RCS ISRC IOUT 1Ω TSD 1/4W LT1970 OUT SENSE+ SENSE– V– R1 LOAD VCSRC = 4V 20µs/DIV –IN V 1970 TA02 EE 10k VC COMMON SNK = 2V RCS = 1Ω R2 10k –15V 1970 TA01 1970fe For more information www.linear.com/LT1970 1 Document Outline Description Typical Application Absolute Maximum Ratings Electrical Characteristics Typical Performance Characteristics Pin Functions Block Diagram Applications Information Package Description Related Parts
