A B C D E REVISION # REVISION HISTORY SD PC FD AD 0 DESCRIPTION 0 0 0 DATE APPROVED 1st Release 4 4 U1 LT3970EMS VIN 6V - 40V L1 22uH CDRH4D22/HPNP-220MC VIN E3 3 C4 + 10uF 50V C3 1uF 50V 0805 E4 GND 3 VOUT R6 VIN 6 9 PG BOOST 7 2 EN BD 8 4 GND FB 1 5 GND RT 10 200k 0402 E6 SW C2 0.1uF 0402 R1 1.00M 1% E1 C1 22uF 6.3V 0805 E2 C5 22pF VOUT 5V / 350mA GND 3 R2 316K 1% R5 226k 1% (600kHz) GND 11 PG VOUT E5 EN VIN 2 1 ON R7 (Opt) 2 2 3 OFF R8 (Opt) JP1 CONTRACT NO. APPROVALS This circuit is proprietary to Linear Technology and supplied for use with Linear Technology parts. Customer Notice: Linear Technology has made a best effort to design a circuit that meets customer-supplied specifications; however, it remains the customers responsibility to verify proper and reliable operation in the actual application, Component substitution and printed circuit board layout may significantly affect circuit performance or reliability. Contact Linear Applications Engineering for assistance. 1 A B DRAWN Rudy Bautista DATE 04/14/09 CHECKED TECHNOLOGY TITLE: APPROVED ENGINEER Molly Zhu DESIGNER SIZE C www.linear.com LTC Confidential For Customer Use Only LT3970EMS 40V 350mA Step-Down Regulator with 2.5uA Quiescent Current and Integrated Diodes CAGE CODE DWG NO SD Tuesday, July 28, 2009 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 Fax: (408)434-0507 FILENAME: C:\ORCADWIN\CAPTURE\1566A\1566A_REV0.DSN D REV Demo Circuit 1566A SHEET 0 OF 1 E 1 1