A7986ATR

A7986A 3 A step-down switching regulator for automotive applications Datasheet - production data Applications Dedicated to automotive applications Automotive LED driving HSOP8 exposed pad Description Features The A7986A is a step-down switching regulator with a 3.7 A (min.) current limited embedded AEC-Q100 qualified power MOSFET, so it is able to deliver up to 3 A 3 A DC output current current to the load depending on the application 4.5 V to 38 V input voltage conditions. Output voltage adjustable from 0.6 V The input voltage can range from 4.5 V to 38 V, 250 kHz switching frequency, programmable while the output voltage can be set starting from up to 1 MHz 0.6 V to VIN. Internal soft-start and enable Requiring a minimum set of external components, the device includes an internal 250 kHz switching Low dropout operation: 100% duty cycle frequency oscillator that can be externally Voltage feed-forward adjusted up to 1 MHz. Zero load current operation The HSOP8 package with exposed pad allows Overcurrent and thermal protection the reduction of R down to 40 C/W. th(JA) HSOP8 package Figure 1. Application circuit February 2017 DocID022801 Rev 8 1/42 This is information on a product in full production. www.st.comContents A7986A 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 12 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 23 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 DocID022801 Rev 8