STEVAL-ISA200V1 STMicroelectronics

STEVAL-ISA200V1 High efficiency synchronous step-down regulator based on the A6984 Data brief V maximizes efficiency at light load BIAS 350 mA valley current limit Constant on-time control scheme PGOOD open collector Thermal shutdown RoHS compliant Description The STEVAL-ISA200V1 product evaluation board is based on the A6984 high-efficiency monolithic synchronous step-down regulator, capable of delivering up to 400 mA of DC current. The fixed 3.3 V output requires no external resistor divider. The A6984 is especially suited for automotive systems. The low consumption mode (LCM) is designed for automotive applications that remain active while the car is parked, maximizing efficiency at light load with controlled output voltage ripple. The low noise mode (LNM) renders the switching frequency nearly constant Features over the load current range, serving low noise AECQ100 qualification application specifications such as audio and 400 mA DC output current sensors. The PGOOD open collector output can 4.5 V to 36 V operating input voltage implement output voltage sequencing during the power-up phase. The synchronous rectification, Synchronous rectification designed for high efficiency at medium-heavy Low consumption mode or low noise mode load, and the high switching frequency capability 100 A I at light load (LCM V = 3.3 V) Q OUT ensure a compact application size. Pulse-by- 13 A I Q-SHTDWN pulse current sensing on the low-side power Adjustable f (250 kHz - 600 kHz) SW element implements effective constant current Output voltage adjustable from 0.9 V protection. No resistor divider required for 3.3 V VOUT March 2017 DocID030364 Rev 1 1/4 www.st.com Schematic diagrams STEVAL-ISA200V1 1 Schematic diagrams Figure 1: STEVAL-ISA200V1 ciruit schematic TP1 VBIAS R4 1M TP2 A6984 PGOOD U1 TP3 R5 NM 7 1 VIN VIN PGOOD TP4 9 J1 VOUT R1 1Meg VBIAS R6 3 L1 68uH TON 100k 6 LX TP5 4 EN EN R9 NM C9 NM 8 J2 VCC 10 LNM C10 NM 2 FB EP GND C3 NM J4 R7 R8 C8 C4 C5 11 5 NM 0 NM NM J3 470nF R3 NM TP6 GND R2 NM TP7 L1: LPS6225- 683MLC GND C1: si ze 1210 C6, C7: si ze 1206 J4 passo 2. 54 2/4 DocID030364 Rev 1 C1 10uF 50V C2 100nF 50V C6 22uF C7 NM