STEVAL-ISA200V1 High efficiency synchronous step-down regulator based on the A6984 Data brief VBIAS maximizes efficiency at light load 350 mA valley current limit Constant on-time control scheme PGOOD open collector Thermal shutdown RoHS compliant Description Features AECQ100 qualification 400 mA DC output current 4.5 V to 36 V operating input voltage Synchronous rectification Low consumption mode or low noise mode 100 A IQ at light load (LCM VOUT = 3.3 V) 13 A IQ-SHTDWN Adjustable fSW (250 kHz - 600 kHz) Output voltage adjustable from 0.9 V No resistor divider required for 3.3 V VOUT March 2017 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 over the load current range, serving low noise application specifications such as audio and sensors. The PGOOD open collector output can implement output voltage sequencing during the power-up phase. The synchronous rectification, designed for high efficiency at medium-heavy load, and the high switching frequency capability ensure a compact application size. Pulse-bypulse current sensing on the low-side power element implements effective constant current protection. DocID030364 Rev 1 1/4 www.st.com Schematic diagrams 1 STEVAL-ISA200V1 Schematic diagrams Figure 1: STEVAL-ISA200V1 ciruit schematic TP1 R4 VBIAS TON LX TP5 4 50V 100nF C1 J4 C2 50V 10uF EN TP6 PGOOD EN VCC 10 LNM FB GND EP R7 R8 NM 0 C8 11 5 NM 1 9 TP4 J1 L1 6 8 R9 J2 C4 J3 R3 R2 NM LPS6225- 683MLC s i z e 1210 C6, C7: NM NM C3 NM GND C1: VOUT NM C5 470nF L1: NM C9 C10 2 PGOOD 68uH NM NM 3 VIN C7 R6 100k 1Meg VBIAS NM 22uF R1 R5 C6 7 VIN TP2 A6984 U1 TP3 1M TP7 GND s i z e 1206 J 4 pas s o 2. 54 2/4 DocID030364 Rev 1 STEVAL-ISA200V1 2 Revision history Revision history Table 1: Document revision history Date Version Changes 30-Mar-2017 1 Initial release. DocID030364 Rev 1 3/4 STEVAL-ISA200V1 IMPORTANT NOTICE - PLEASE READ CAREFULLY STMicroelectronics NV and its subsidiaries ("ST") reserve the right to make changes, corrections, enhancements, modifications, and improvements to ST products and/or to this document at any time without notice. Purchasers should obtain the latest relevant information on ST products before placing orders. ST products are sold pursuant to ST's terms and conditions of sale in place at the time of order acknowledgement. Purchasers are solely responsible for the choice, selection, and use of ST products and ST assumes no liability for application assistance or the design of Purchasers' products. No license, express or implied, to any intellectual property right is granted by ST herein. Resale of ST products with provisions different from the information set forth herein shall void any warranty granted by ST for such product. ST and the ST logo are trademarks of ST. All other product or service names are the property of their respective owners. Information in this document supersedes and replaces information previously supplied in any prior versions of this document. (c) 2017 STMicroelectronics - All rights reserved 4/4 DocID030364 Rev 1