L6986 38 V, 2 A synchronous step-down switching regulator with 30 A quiescent current Datasheet - production data Description The L6986 device is a step-down monolithic switching regulator able to deliver up to 2 A DC. The output voltage adjustability ranges from 0.85 V to VIN. Thanks to the P-channel MOSFET high-side power element, the device features HTSSOP16 (R = 40 C/W) 100% duty cycle operation. The wide input TH voltage range meets the specification for the 5 V, 12 V and 24 V power supplies. The Low Consumption Mode (LCM) is designed for Features applications active during idle mode, so it maximizes the efficiency at light load with 2 A DC output current controlled output voltage ripple. The Low Noise 4 V to 38 V operating input voltage Mode (LNM) makes the switching frequency Low consumption mode or low noise mode constant overload current range, meeting the low noise application specification. The output voltage 30 A IQ at light load (LCM V = 3.3 V) OUT supervisor manages the reset phase for any 8 A I Q-SHTDWN digital load ( C, FPGA, etc.). The RST open Adjustable f (250 kHz - 2 MHz) SW collector output can also implement output voltage sequencing during the power-up phase. Output voltage adjustable from 0.85 V to V IN The synchronous rectification, designed for high Embedded output voltage supervisor efficiency at medium - heavy load, and the high Synchronization switching frequency capability make the size of the application compact. Pulse by pulse current Adjustable soft-start time sensing on both power elements implements an Internal current limiting effective constant current protection. Overvoltage protection Output voltage sequencing Peak current mode architecture R = 180 m , R = 150 m DSON HS DSON LS Thermal shutdown Applications Designed for 12 V and 24 V buses Programmable logic controllers (PLCs) Decentralized intelligent nodes Sensors and low noise applications (LNM) August 2016 DocID025376 Rev 7 1/68 This is information on a product in full production. www.st.comContents L6986 Contents 1 Application schematic . 4 2 Pin settings 5 2.1 Pin connection 5 2.2 Pin description 5 2.3 Maximum ratings 6 2.4 Thermal data . 7 2.5 ESD protection 7 3 Electrical characteristics . 8 4 Functional description 13 4.1 Power supply and voltage reference 14 Switchover feature . 14 4.2 Voltages monitor 14 4.3 Soft-start and inhibit . 15 4.3.1 Ratiometric startup . 21 4.3.2 Output voltage sequencing 22 4.4 Error amplifier 23 4.5 Light load operation . 24 4.5.1 Low noise mode (LNM) . 24 4.5.2 Low consumption mode (LCM) . 24 4.6 Switchover feature 27 4.6.1 LCM 27 4.6.2 LNM 27 4.7 Overcurrent protection . 28 OCP and switchover feature . 30 4.8 Overvoltage protection . 32 4.9 Thermal shutdown 33 2/68 DocID025376 Rev 7