L7986TA 3 A step-down switching regulator Datasheet - production data Description The L7986TA is a step-down switching regulator with 3.7 A (min.) current limited embedded Power MOSFET, so it is able to deliver up to 3 A current to the load depending on the application conditions. The input voltage can range from 4.5 V to 38 V, HSOP8 exposed pad while the output voltage can be set starting from 0.6 V to V . IN Requiring a minimum set of external components, Features the device includes an internal 250 kHz switching frequency oscillator that can be externally 3 A DC output current adjusted up to 1 MHz. 4.5 V to 38 V input voltage The HSOP package with exposed pad allows the Output voltage adjustable from 0.6 V reduction of R down to 40 C/W. thJA 250 kHz switching frequency, programmable up to 1 MHz Internal soft-start and enable Low dropout operation: 100% duty cycle Voltage feed-forward Zero load current operation Overcurrent and thermal protection HSOP8 package Guarantee overtemperature range (-40 C to 125 C) Applications Automotive: Car audio, car infotainment Industrial: PLD, PLA, FPGA, chargers Networking: XDSL, modems, DC-DC modules Computer: Optical storage, hard disk drive, printers LED driving March 2014 DocID022098 Rev 4 1/42 This is information on a product in full production. www.st.comContents L7986TA Contents 1 Pin settings 4 1.1 Pin connection 4 1.2 Pin description 4 2 Maximum ratings 5 3 Thermal data . 5 4 Electrical characteristics . 6 5 Functional description . 8 5.1 Oscillator and synchronization 9 5.2 Soft-start .11 5.3 Error amplifier and compensation .11 5.4 Overcurrent protection . 12 5.5 Enable function 14 5.6 Hysteretic thermal shutdown 14 6 Application information . 15 6.1 Input capacitor selection 15 6.2 Inductor selection . 16 6.3 Output capacitor selection 17 6.4 Compensation network . 18 6.4.1 Type III compensation network . 20 6.4.2 Type II compensation network 24 6.5 Thermal considerations 27 6.6 Layout considerations . 28 6.7 Application circuit . 30 7 Application ideas . 34 7.1 Positive buck-boost . 34 7.2 Inverting buck-boost . 36 2/42 DocID022098 Rev 4