B C D E F VL 2.9V - 5.5V L1 1 GND 4 LINE IN CAP TOUT TIN RIN ROUT 11 12 6 VDD C3 R24 100 1206 COM PORT (DB9) GND E17 GND E18 GND E15 E7 GND COM PORT ENABLE VL J11 TXn 4 OUT 5 R16 100k RXD1 E12 VDD ECO REV DESCRIPTION APPROVED DATE - 2 1ST PROTOTYPE KEITH B. 9-17-12 ADJ SHDN 75k GND EXT DB9 VL TXn VL 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 TXD2 GND EXT DB9 VL IRQ SDO E6 RXD3 E5 R8 100 TXn 1206 JP4 SDI SCK CS VL TXD3 GND EXT DB9 VL 6 SCK CS E3 RXD4 E2 RXD1 TXD1 TXEN1 IRQ SDO RXD2 TXD2 TXEN2 VL GND GND SDI SCK CS RXD3 TXD3 TXEN3 RXD4 TXD4 0.2 0805 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 C13 8 VL R22 4.99k D13 RED VL OPEN C12 10 OPEN R30 R14 R15 VL JP7 VL EXT GND IRQ R11 100 1206 IRQ 4.99k D8 36V 4.99k E11 TXEN1 4.99k OPEN JP3 0.2 Q3 FQT7N10 D3 R28 0805 J7 1 S100 D9 36V C20 R3 C15 L+3 6 2 I/Q3 3 OPEN C14 10 D10 36V L-3 4 OPEN C/Q3 5 NC3 J3 VL EXT GND TXEN2 R9 100 1206 R7 100 1206 0.2 VL EXT GND TXEN3 Q4 FQT7N10 0805 S100 C21 R4 C17 R5 100 1206 E4 E1 TXEN2 TXEN3 TXEN4 7 J8 1 D11 36V L+4 2 I/Q4 8 3 TXEN4 E8 2 1 5 4 3 I/Q4 L+4 NC4 C/Q4 L-4 D4 5 2 1 5 4 3 I/Q3 L+3 NC3 C/Q3 L-3 JP1 VL EXT GND OPEN C16 10 OPEN R32 D12 36V L-4 4 OPEN C/Q4 5 OPEN NC4 JP13 J4 GND - SHIELD 0.1uF/25V 5 6 7 8 NC2 J2 VL CUSTOMER NOTICE APPROVALS 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 LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT PERFORMANCE OR RELIABILITY. CONTACT LINEAR TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE. PCB DES. KEITH B. 9 VSS SDA A2 SCL A1 WP A0 VCC C/Q2 5 C7 U4 24LC025 4 3 2 1 NOTES: UNLESS OTHERWISE SPECIFIED 1. ALL RESISTORS ARE IN OHMS, 0603. ALL CAPACITORS ARE IN MICROFARADS, 0603. 10 A L-2 4 OPEN R26 JP9 IRQ I/Q2 3 OPEN GND EXT DB9 VL R23 680 4 L+2 2 VL TXEN1 R13 D7 36V C19 VL 2 4 6 8 10 12 14 J6 1 TXD4 1 3 5 7 9 11 13 3 NC1 2 1 5 4 3 TXn CS C/Q1 J1 S100 JP2 7 L-1 5 R2 L+1 SENSE-1 GATE1 CQ1 CQ2 L+2 SENSE-2 GATE2 VDD SENSE+ L+3 SENSE-3 GATE3 CQ3 CQ4 L+4 SENSE-4 GATE4 TXEN4 I/Q1 4 OPEN OPEN R31 1206 J12 DC590 D6 36V Q2 FQT7N10 D2 R27 R6 100 TXD4 SCK OPEN C10 10 I/Q2 L+2 NC2 C/Q2 L-2 U1 LTC2874IFE 1uF/16V JP8 L+1 2 3 JP12 LDO ON 47.5k C1 TXD3 C18 59k R21 VL SELECT 2 OPEN 309k R20 3.3V 5.0V 5.5V R10 100 5 D5 36V R1 R19 JP11 E10 1206 S100 11 J5 1 10k TXD1 E9 13 0805 R18 JP10 TXD2 0.2 Q1 FQT7N10 D1 R25 OPEN R29 2.9V 2 1 5 4 3 I/Q1 L+1 NC1 C/Q1 L-1 6 R17 RXD2 1 E16 C11 R12 100 TXn IN VL 4 L REVISION HISTORY 1uF/50V 0805 U3 LT3012 E13 C4 K 100uF/63V DIA=12.5mm C2 RXDn COM PORT SELECT JP6 1206 SDI SDO J10 J C9 4.7uF/16V 3528 TXD1 SDO VDD 8V - 30V C8 1uF/16V 1uF/16V SDI I GND RXD4 RXD3 RXD2 RXD1 7 2 1 1uF/16V 3 VCC VL PS MODE LINE OUT 220nF/16V 3 10 8 9 VEE 1 6 2 7 3 8 4 9 5 DCD DSR RX RTS TX CTS DTR C6 13 2 SW C5 H VL 10uH U2 LTC2802 J9 GND E14 JP5 5 G GND A B C D E F THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS. G H TECHNOLOGY APP ENG. KEITH B. 1630 McCarthy Blvd. Milpitas, CA 95035 LTC CONFIDENTIAL Phone: (408) 432-1900 FOR CUSTOMER Fax: (408) 434-0507 USE ONLY www.linear.com TITLE: SCHEMATIC QUAD INDUSTRIAL BUS MASTER CONTROLLER SIZE IC NO. SCALE = NONE I DATE: REV. LTC2874IFE DEMO CIRCUIT 1880A N/A Monday, October 28, 2013 J 2 SHEET K 1 OF L 1 9