5 4 3 2 1 REVISION HISTORY ECO REV __ 1 DESCRIPTION APPROVED DATE 1ST PROTOTYPE MARK T. 02-07-14 VCC VCC EXT VCC REFSEL 1 2 3 EXT INT JP1 IDLSEL HI-Z#/HOLD ZS#/FS JP2 VCC C2 0.1uF 1 2 3 JP3 E8 IDLSEL 4 REFSEL 13 7 IOVCC INC IND GND PD REF 12 IOVCC C3 0.1uF E9 INA 6 E10 INB 5 E11 INC 11 E12 IND 10 E13 NPD 9 INA VOUTA INB VOUTB INC VOUTC IND VOUTD PD E15 PD ON PD VCC 1 2 3 VCC E16 * E1 REF C1 10uF 6.3V 0805 8 C U1 LTC2645 E6 2 VOUTA E2 3 VOUTB E3 14 VOUTC E4 15 VOUTD E5 E7 GND INA INB E14 REFSEL GND GND IDLSEL D VCC REF GND VOUTA VOUTB VOUTC VOUTD GND C 16 IOVCC VCC 1 2 3 1 IOVCC VCC D R1 10k JP4 LINDUINO HEADERS VIN AD0 AD1 AD2 AD3 SDA SCL 1 2 3 4 5 6 1 2 3 4 5 6 POWER HD1X6-100 ADO HD1X6-100 R9 49.9 R10 49.9 R11 49.9 DACS C AND D CONNECTED TO 8-BIT CAPABLE PWM LINDUINO OUTPUTS NOTE: UNLESS OTHERWISE SPECIFIED 1. ALL RESISTORS AND CAPACITORS ARE 0603. CUSTOMER NOTICE APPROVALS LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS; HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO PCB DES. VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL APP ENG. APPLICATION. COMPONENT SUBSTITUTION AND PRINTED CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. 4 3 U1 LTC2645-L12 ASSY TYPE A * A 5 B DACS A AND B CONNECTED TO 16-BIT CAPABLE PWM LINDUINO OUTPUTS IO5 IO6 TEST PADS ALLOW REMAPPING LINDUINO CONNECTIONS TPC INC INB 8 7 6 5 4 3 2 1 IO7 IO6 IO5 IO4 IO3 IO2 IO1 IO0 R8 49.9 R7 49.9 VCC RESET +3V3 R2 OPT TPD IO2 IO10 8 7 6 5 4 3 2 1 IO13 IO12 IO11 IO10 IO9 IO8 AREF VCC TPA IND TPB IOL1 HD1X8-100 INA IOH1 HD1X8-100 IO9 B TECHNOLOGY KIM T. MARK T. SUFFIX 12 -BIT 12 1630 McCarthy Blvd. Milpitas, CA 95035 Phone: (408)432-1900 www.linear.com Fax: (408)434-0507 LTC Confidential-For Customer Use Only TITLE: SCHEMATIC QUAD 12/10/8-BIT PWM TO VOUT DACS SIZE N/A SCALE = NONE 2 DATE: IC NO. LTC2645CMS FAMILY REV. 1 DEMO CIRCUIT 2197A 02/07/2014, 11:20 AM SHEET 1 1 OF 1 A