LTC2845

LTC2845 3.3V Software-Selectable Multiprotocol Transceiver FEATURES s s DESCRIPTIO s s s Software-Selectable Transceiver Supports: RS232, RS449, EIA530, EIA530-A, V.35, V.36, X.21 Operates from Single 3.3V Supply with LTC2846 or a Single 5V Supply with 3.3V Logic with LTC2847 TUV Rheinland of North America Inc. Certified NET1, NET2 and TBR2 Compliant, Report No.: TBR2/050101/02 Complete DTE or DCE Port with LTC2846 or LTC2847 Available in a 36-Lead Narrow (0.209") SSOP and 38-Lead (7mm x 5mm) QFN package The LTC®2845 is a 5-driver/5-receiver multiprotocol transceiver. The LTC2845 and LTC2846 form the core of a complete software-selectable DTE or DCE interface port that supports the RS232, RS449, EIA530, EIA530-A, V.35, V.36 or X.21 protocols. The LTC2845 operates from a 3.3V supply and supplies provided by the LTC2846. This part is available in a 36-lead SSOP and 38-lead (7mm x 5mm) QFN package. The LTC2845 and LTC2847 in QFN packages offer the smallest multiprotocol serial port available. , LTC and LT are registered trademarks of Linear Technology Corporation. APPLICATIO S s s s Data Networking CSU and DSU Data Routers TYPICAL APPLICATIO DTE or DCE Multiprotocol Serial Interface with DB-25 Connector RL TM RI LL CTS DSR DCD DTR RTS RXD RXC TXC SCTE TXD LTC2845 D5 R5 R4 D4 D3 R3 R2 R1 D2 D1 R3 R2 R1 T T 21 RL A (140) 25 TM A (142) * RI A (125) 18 13 5 LL A (141) CTS B CTS A (106) DSR B 22 6 DSR A (107) 10 8 DCD B DCD A (109) 23 20 19 4 DTR B DTR A (108) RTS B RTS A (105) SHIELD (101) 1 SG (102) 7 16 RXD B 3 RXD A (104) 9 RXC B 17 RXC A (115) DB-25 CONNECTOR U LTC2846 D3 D2 D1 T T T 12 TXC B TXC A (114) U U 15 11 SCTE B SCTE A (113) 24 14 TXD B 2 TXD A (103) *OPTIONAL 2845 TA01 sn2845 2845fs 1 LTC2845 ABSOLUTE MAXIMUM RATINGS Supply Voltage VCC ....................................................... –0.3V to 6.5V VIN ..................................................................... – 0.3V to 6.5V VEE ...................................................................... –10V to 0.3V VDD ..................................................................... – 0.3V to 10V Input Voltage Transmitters ........................... – 0.3V to (VCC + 0.3V) Receivers ............................................... – 18V to 18V Logic Pins .............................. – 0.3V to (VCC + 0.3V) Output Voltage Transmitters .................. (VEE – 0.3V) to (VDD + 0.3V) Receivers ................................. – 0.3V to (VIN + 0.3V) PACKAGE/ORDER INFORMATION TOP VIEW VCC VDD D1 D2 D3 R1 R2 R3 D4 1 2 3 4 5 6 7 8 9 R1 R2 R3 D4 R4 R5 D5 G PACKAGE 36-LEAD PLASTIC SSOP D3 D1 D2 36 VEE 35 GND 34 D1 A 33 D1 B 32 D2 A 31 D2 B 30 D3/R1 A 29 D3/R1 B 28 R2 A 27 R2 B 26 R3 A 25 R3 B 24 D4 A 23 R4 A 22 R5 A 21 D5 A 20 VIN 19 VCC ORDER PART NUMBER LTC2845CG LTC2845IG D2 1 D3 2 R1 3 R2 4 R3 5 D4 6 R4 7 M0 8 M1 9 M2 10 NC 11 DCE/DTE 12 38 37 36 35 34 33 32 31 D1 B 30 D2 A 29 D2 B 28 D3/R1 A 27 D3/R1 B 39 26 R2 A 25 R2 B 24 R3 A 23 R3 B 22 D4 A 21 R4 A 20 R5 A 13 14 15 16 17 18 19 R5 D5 VCC VIN D4ENB R4EN D5 A D1 A GND VDD VCC VEE VEE D1 R4 10 M0 11 M1 12 M2 13 DCE/DTE 14 D4ENB 15 R4EN 16 R5 17 D5 18 TJMAX = 125°C, θJA = 90°C/ W, θJC = 35°C/ W Consult LTC Marketing for parts specified with wider operating temperature ranges. The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VCC = 5V, VIN = 3.3V, VDD = 8V, VEE = – 7V for V.28, – 5.5V for V.10, V.11 (Notes 2, 3) SYMBOL Supplies ICC VCC Supply Current (DCE Mode, All Digital Pins = GND or VIN) RS530, RS530-A, X.21 Modes, No Load RS530, RS530-A, X.21 Modes, Full Load V.28 Mode, No Load V.28 Mode, Full Load No-Cable Mode q q q q ELECTRICAL CHARACTERISTICS PARAMETER CONDITIONS 2 U U W WW U W (Note 1) Short-Circuit Duration Transmitter Output ..................................... Indefinite Receiver Output .......................................... Indefinite VEE .................................................................. 30 sec Operating Temperature Range LTC2845C ............................................... 0°C to 70°C LTC2845I ........................................... – 40°C to 85°C Storage Temperature Range ................ – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................. 300°C TOP VIEW ORDER PART NUMBER LTC2845CUHF LTC2845IUHF UHF PART MARKING 2845 2845I UHF PACKAGE 38-LEAD (7mm × 5mm) PLASTIC QFN TJMAX = 125°C, θJA = 34°C/ W EXPOSED PAD IS VEE (PIN 39) MUST BE SOLDERED TO PCB MIN TYP 2.7 110 1 1 700 MAX UNITS mA mA mA mA µA sn2845 2845fs 150 3 3 1400 LTC2845 The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VCC = 5V, VIN = 3.3V, VDD = 8V, VEE = – 7V for V.28, – 5.5V for V.10, V.11 (Notes 2, 3) SYMBOL IEE PARAMETER VEE Supply Current (DCE Mode, All Digital Pins = GND or VIN) CONDITIONS RS530, RS530-A, X.21 Modes, No Load RS530, X.21 Modes, Full Load RS530-A, Full Load V.28 Mode, No Load V.28 Mode, Full Load No-Cable Mode RS530, RS530-A, X.21 Modes, No Load RS530, RS530-A, X.21 Modes, Full Load V.28 Mode, No Load V.28 Mode, Full Load No-Cable Mode All Modes Except No-Cable Mode RS530, RS530-A, X.21 Modes, Full Load V.28 Mode, Full Load q ELECTRICAL CHARACTERISTICS MIN TYP 2 23 34 1 12 10 0.3 0.3 1 13.5 10 650 240 64 MAX UNITS mA mA mA mA mA µA mA mA mA mA µA µA mW mW V IDD VDD Supply Current (DCE Mode, All Digital Pins = GND or VIN) IVIN PD VIN Supply Current (DCE Mode, All Digital Pins = GND or VIN) Internal Power Dissipation (DCE Mode, All Digital Pins = GND or VIN) Logic Input High Voltage Logic Input Low Voltage Logic Input Current Logic Inputs and Outputs VIH VIL IIN 2 0.8 0.5 –30 2.7 –75 3 0.2 –30 –85 0.4 ±50 –160 ±10 ±5 0.5VODO ±2 0.67VODO 0.2 3 0.2 ±150 q q q q q q q q q VCC = 5V R4EN when VCC = 3.3V D1, D2, D3, D4, D5 M0, M1, M2, DCE, D4ENB, R4EN = GND M0, M1, M2, DCE, D4ENB, R4EN = VIN IO = –3mA IO = 1.6mA 0V ≤ VO ≤ VIN M0 = M1 = M2 = VIN, VO = GND M0 = M1 = M2 = VIN, VO = VIN RL = 1.95k (Figure 1) RL = 50Ω (Figure 1) q q q q q q q q q V V µA µA µA V V mA µA µA V V V V V V mA µA ns ns ns ns ns ns ns ns ns sn2845 2845fs ±10 –120 ±10 VOH VOL IOSR IOZR V.11 Driver VODO VODL ∆VOD VOC ∆VOC ISS IOZ tr, tf tPLH tPHL ∆t tSKEW Output High Voltage Output Low Voltage Output Short-Circuit Current Three-State Output Current Open Circuit Differential Output Voltage Loaded Differential Output Voltage Change in Magnitude of Differential Output Voltage Common Mode Output Voltage Change in Magnitude of Common Mode Output Voltage Short-Circuit Current Output Leakage Current Rise or Fall Time Input to Output Input to Output Input to Output Difference, tPLH – tPHL Output to Output Skew q q RL = 50Ω (Figure 1) RL = 50Ω (Figure 1) RL = 50Ω (Figure 1) VOUT = GND –0.25V ≤ VO ≤ 0.25V, Power Off or No-Cable Mode or Driver Disabled LTC2845C (Figures 2, 5) LTC2845I (Figures 2, 5) LTC2845C (Figures 2, 5) LTC28451 (Figures 2, 5) LTC2845C (Figures 2, 5) LTC2845I (Figures 2, 5) LTC2845C (Figures 2, 5) LTC2845I (Figures 2, 5) (Figures 2, 5) q q q ±1 2 2 20 20 20 20 0 0 15 15 40 40 40 40 3 3 3 ±100 25 35 65 75 65 75 12 17 3 LTC2845 The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VCC = 5V, VIN = 3.3V, VDD = 8V, VEE = – 7V for V.28, – 5.5V for V.10, V.11 (Notes 2, 3) SYMBOL VTH ∆VTH IIN RIN tr, tf tPLH tPHL ∆t V.10 Driver VO VT ISS IOZ tr, tf tPLH tPHL VTH ∆VTH IIN RIN tr, tf tPLH tPHL ∆t V.28 Driver VO ISS IOZ SR tPLH tPHL Output Voltage Short-Circuit Current Output Leakage Current Slew Rate Input to Output Input to Output Open Circuit RL = 3k (Figure 3) VO = GND –0.25V ≤ VO ≤ 0.25V, Power Off or No-Cable Mode or Driver Disabled RL = 3k, CL = 2500pF (Figures 3, 7) RL = 3k, CL = 2500pF (Figures 3, 7) RL = 3k, CL = 2500pF (Figures 3, 7) q q q q q q q ELECTRICAL CHARACTERISTICS PARAMETER Input Threshold Voltage Input Hysteresis Input Current (A, B) Input Impedance Rise or Fall Time Input to Output Input to Output Input to Output Difference, tPLH – tPHL CONDITIONS –7V ≤ VCM ≤ 7V –7V ≤ VCM ≤ 7V –10V ≤ VA,B ≤ 10V –10V ≤ VA,B ≤ 10V (Figures 2, 6) LTC2845C CL = 50pF (Figures 2, 6) LTC2845I CL = 50pF (Figures 2, 6) LTC2845C CL = 50pF (Figures 2, 6) LTC2845I CL = 50pF (Figures 2, 6) LTC2845C CL = 50pF (Figures 2, 6) LTC2845I CL = 50pF (Figures 2, 6) Open Circuit, RL = 3.9k RL = 450Ω (Figure 3) RL = 450Ω (Figure 3) VO = GND –0.25V ≤ VO ≤ 0.25V, Power Off or No-Cable Mode or Driver Disabled RL = 450Ω, CL = 100pF (Figures 3, 7) RL = 450Ω, CL = 100pF (Figures 3, 7) RL = 450Ω, CL = 100pF (Figures 3, 7) q q q q q q q q q q q q q MIN –0.2 TYP MAX 0.2 UNITS V mV mA kΩ ns V.11 Receiver 15 15 30 15 50 50 50 50 0 0 ±4 ±3.6 0.9VO ±150 ±0.1 2 1 1 –0.25 25 15 30 15 55 109 60 ±10 ±150 ±1 4 1.3 1.3 ±100 30 2.5 2.5 0.25 50 ±0.66 ±100 4 4 80 90 80 90 16 21 ±6 40 ±0.66 ns ns ns ns ns ns V V mA µA µs µs µs V mV mA kΩ ns ns ns ns V V mA µA V/µs µs µs Output Voltage Output Voltage Short-Circuit Current Output Leakage Current Rise or Fall Time Input to Output Input to Output Receiver Input Threshold Voltage Receiver Input Hysteresis Receiver Input Current Receiver Input Impedance Rise or Fall Time Input to Output Input to Output Input to Output Difference, tPLH – tPHL q q V.10 Receiver –10V ≤ VA ≤ 10V –10V ≤ VA ≤ 10V CL = 50pF (Figures 4, 8) CL = 50pF (Figures 4, 8) CL = 50pF (Figures 4, 8) CL = 50pF (Figures 4, 8) q q ±5 ±8.5 sn2845 2845fs 4 LTC2845 The q denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VCC = 5V, VIN = 3.3V, VDD = 8V, VEE = – 7V for V.28, – 5.5V for V.10, V.11 (Notes 2, 3) SYMBOL PARAMETER V.28 Receiver VTHL Input Low Threshold Voltage VTLH Input High Threshold Voltage ∆VTH Receiver Input Hysterisis RIN Receiver Input Impedance tr, tf Rise or Fall Time tPLH Input to Output tPHL Input to Output CONDITIONS q q q ELECTRICAL CHARACTERISTICS MIN TYP MAX 0.8 UNITS V V V kΩ ns ns ns 2 3 0.1 5 15 60 150 0.3 7 100 500 –15V ≤ VA ≤ 15V CL = 50pF (Figures 4, 8) CL = 50pF (Figures 4, 8) CL = 50pF (Figures 4, 8) q q q Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: All currents into device pins are positive; all currents out of device are negative. All voltages are referenced to device ground unless otherwise specified. Note 3: All typicals are given for VCC = 5V, VIN = 3.3V, VDD = 8V, VEE = – 7V for V.28, – 5.5V for V.10, V.11 and TA = 25°C. TYPICAL PERFOR A CE CHARACTERISTICS RS530, X.21 in DCE Mode (Three V.11, Two V.10 Drivers with Full Load) ICC vs Data Rate 140 135 130 TA = 25°C 34 34 30 28 ICC (mA) IDD (mA) IEE (mA) 125 120 115 110 105 10 100 1000 DATA RATE (kBd) 10000 2845 G01 125 120 115 RS530, X.21 in DCE Mode (Three V.11, Two V.10 Drivers with Full Load) ICC vs Temperature 34.6 34.4 34.2 110 105 100 95 –40 –20 33.8 33.6 33.4 33.2 IDD (mA) ICC (mA) IEE (mA) 20 60 0 40 TEMPERATURE (°C) UW 80 2845 G04 RS530-A in DCE Mode (Three V.10 Drivers with Full Load) IEE vs Data Rate TA = 25°C 16 15 14 13 12 11 10 9 8 10 30 40 50 60 70 80 100 20 DATA RATE (kBd) 2845 G02 7 V.28 in DCE Mode (Five V.28 Drivers with Full Load) IDD vs Data Rate TA = 25°C 26 24 22 20 18 10 20 30 40 50 60 70 80 100 2845 G03 DATA RATE (kBd) RS530-A in DCE Mode (Three V.10 Drivers with Full Load) IEE vs Temperature 13.9 13.8 13.7 13.6 13.5 13.4 13.3 13.2 0 20 40 60 TEMPERATURE (°C) 80 100 V.28 in DCE Mode (Five V.28 Drivers with Full Load) IDD vs Temperature 34.0 100 33.0 –40 –20 13.1 –40 –20 2845 G05 0 20 40 60 TEMPERATURE (°C) 80 100 2845 G06 sn2845 2845fs 5 LTC2845 PIN FUNCTIONS VCC (Pins 1, 19/Pins 17, 36): Positive Supply for the Transceivers. Connect to VCC Pin 8 on LTC2846 or to 5V supply. Connect a 1µF capacitor to ground. VDD (Pin 2/Pin 37): Positive Supply Voltage for V.28. Connect to VDD Pin 7 on LTC2846 or 8V supply. Connect a 1µF capacitor to ground. D1 (Pin 3/Pin 38): TTL Level Driver 1 Input. D2 (Pin 4/Pin 1): TTL Level Driver 2 Input. D3 (Pin 5/Pin 2): TTL Level Driver 3 Input. R1 (Pin 6/Pin 3): CMOS Level Receiver 1 Output. Receiver outputs have a weak pull up to VIN when high impedance. R2 (Pin 7/Pin 4): CMOS Level Receiver 2 Output. R3 (Pin 8/Pin 5): CMOS Level Receiver 3 Output. D4 (Pin 9/Pin 6): TTL Level Driver 4 Input. R4 (Pin 10/Pin 7): CMOS Level Receiver 4 Output. M0 (Pin 11/Pin 8): TTL Level Mode Select Input 0. Mode select inputs pull up to VIN. M1 (Pin 12/Pin 9): TTL Level Mode Select Input 1. M2 (Pin 13/Pin 10): TTL Level Mode Select Input 2. DCE/DTE (Pin 14/Pin 12): TTL Level Mode Select Input. Logic high enables Driver 3. Logic low enables Receiver 1. D4ENB (Pin 15/Pin 13): TTL Level Enable Input. Logic low enables Driver 4. Pulls up to VIN. R4EN (Pin 16/Pin 14): TTL Level Enable Input. Logic high enables Receiver 4. Pulls up to VIN. R5 (Pin 17/Pin 15): CMOS Level Receiver 5 Output. 6 U U U (G-36/QFN-38 Packages) D5 (Pin 18/Pin 16): TTL Level Driver 5 Input. VIN (Pin 20/Pin 18): Positive Supply for the Receiver Outputs. 3V ≤ VIN ≤ 3.6V. Connect a 1µF capacitor to ground. D5 A (Pin 21/Pin 19): Driver 5 Inverting Output. R5 A (Pin 22/Pin 20): Receiver 5 Inverting Input. R4 A (Pin 23/Pin 21): Receiver 4 Inverting Input. D4 A (Pin 24/Pin 22): Driver 4 Inverting Input. R3 B (Pin 25/Pin 23): Receiver 3 Noninverting Input. R3 A (Pin 26/Pin 24): Receiver 3 Inverting Input. R2 B (Pin 27/Pin 25): Receiver 2 Noninverting Input. R2 A (Pin 28/Pin 26): Receiver 2 Inverting Input. D3/R1 B (Pin 29/Pin 27): Receiver 1 Noninverting Input and Driver 3 Noninverting Output. D3/R1 A (Pin 30/Pin 28): Receiver 1 Inverting Input and Driver 3 Inverting Output. D2 B (Pin 31/Pin 29): Driver 2 Noninverting Output. D2 A (Pin 32/Pin 30): Driver 2 Inverting Output. D1 B (Pin 33/Pin 31): Driver 1 Noninverting Output. D1 A (Pin 34/Pin 32): Driver 1 Inverting Output. GND (Pin 35/Pin 33): Ground. VEE (Pin 36/Pins 34, 35): Negative Supply Voltage. Connect to VEE Pin 31 on LTC2846 or to –7V supply. Connect a 1µF capacitor to ground. EXPOSED Pad VEE (Pin 39): Must be Soldered to PCB. sn2845 2845fs LTC2845 BLOCK DIAGRA VCC 1 VDD 2 D1 3 D1 33 D1B 32 D2A D2 4 D2 31 D2B 30 D3/R1 A D3 5 D3 10k 20k 6k S3 R1 6 R1 28 R2A 20k 10k 6k S3 R2 7 R2 10k R3 8 R3 10k D4 9 D4 R4 10 R4 S3 DCE/DTE 14 D4ENB 15 R4EN 16 10k R5 17 R5 S3 22 R5A 20k 6k D5 18 D5 M0 11 M1 12 M2 13 20 VIN 19 VCC 2845 BD W 36 VEE 35 GND 34 D1A 10k 20k 29 D3/R1 B 27 R2B 20k 26 R3A 20k 10k S3 6k 25 R3B 20k 24 D4A 23 R4A 10k 20k 6k 21 D5A MODE SELECTION LOGIC TEST CIRCUITS A RL VOD RL B VOC 2845 F01 Figure 1. V.11 Driver Test Circuit B A RL 100Ω CL 100pF CL 100pF B A R CL 2845 F02 Figure 2. V.11 Driver/Receiver AC Test Circuit D A CL RL 2845 F03 Figure 3. V.10/V.28 Driver Test Circuit D A A R CL 2845 F04 Figure 4. V.10/V.28 Receiver Test Circuit sn2845 2845fs 7 LTC2845 ODE SELECTIO MODE NAME Not Used (Default V.11) RS530A RS530 X.21 V.35 RS449/V.36 V.28/RS232 No Cable Not Used (Default V.11) RS530A RS530 X.21 V.35 RS449/V.36 V.28/RS232 No Cable M2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 MODE NAME Not Used (Default V.11) RS530A RS530 X.21 V.35 RS449/V.36 V.28/RS232 No Cable Not Used (Default V.11) RS530A RS530 X.21 V.35 RS449/V.36 V.28/RS232 No Cable M2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 Note 1: Driver inputs are TTL level compatible. Note 2: Unused receiver inputs are terminated with 30k to ground. Note 3: Receiver outputs are CMOS level compatible and have a weak pull-up to VIN when Z. Note 4: Driver 4 is enabled by D4ENB=0 (Pin 15). Note 5: Receiver 4 is enabled by R4EN=1 (Pin 16). 8 U M1 M0 DCE /DTE 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 (Note 1) (Note 4) (Note 1) D1, D2, D3 D4, D5 TTL TTL TTL TTL TTL TTL TTL X TTL TTL TTL TTL TTL TTL TTL X X X X X X X X X TTL TTL TTL TTL TTL TTL TTL X D1 A V.11 V.11 V.11 V.11 V.28 V.11 V.28 Z V.11 V.11 V.11 V.11 V.28 V.11 V.28 Z B V.11 V.11 V.11 V.11 Z V.11 Z Z V.11 V.11 V.11 V.11 Z V.11 Z Z A V.11 V.10 V.11 V.11 V.28 V.11 V.28 Z V.11 V.10 V.11 V.11 V.28 V.11 V.28 Z D2 B V.11 Z V.11 V.11 Z V.11 Z Z V.11 Z V.11 V.11 Z V.11 Z Z A Z Z Z Z Z Z Z Z V.11 V.11 V.11 V.11 V.28 V.11 V.28 Z D3 B Z Z Z Z Z Z Z Z V.11 V.11 V.11 V.11 Z V.11 Z Z V.10 V.10 V.10 V.10 V.28 V.10 V.28 Z V.10 V.10 V.10 V.10 V.28 V.10 V.28 Z (Note 4) D4A D5A 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 M1 M0 DCE /DTE 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 (Note 2) R1 A B V.11 V.11 V.11 V.11 V.28 V.11 V.28 30k 30k 30k 30k 30k 30k 30k 30k 30k V.11 V.11 V.11 V.11 30k V.11 30k 30k 30k 30k 30k 30k 30k 30k 30k 30k (Note 2) R2 A B V.11 V.10 V.11 V.11 V.28 V.11 V.28 30k V.11 V.10 V.11 V.11 V.28 V.11 V.28 30k V.11 30k V.11 V.11 30k V.11 30k 30k V.11 30k V.11 V.11 30k V.11 30k 30k (Note 2) R3 A B V.11 V.11 V.11 V.11 V.28 V.11 V.28 30k V.11 V.11 V.11 V.11 V.28 V.11 V.28 30k V.11 V.11 V.11 V.11 30k V.11 30k 30k V.11 V.11 V.11 V.11 30k V.11 30k 30k (Note 2) (Note 3) (Note 5) (Note 3) (Note 5) R4A R1 R2, R3 R5A R4, R5 V.10 V.10 V.10 V.10 V.28 V.10 V.28 30k V.10 V.10 V.10 V.10 V.28 V.10 V.28 30k CMOS CMOS CMOS CMOS CMOS CMOS CMOS Z Z Z Z Z Z Z Z Z CMOS CMOS CMOS CMOS CMOS CMOS CMOS Z CMOS CMOS CMOS CMOS CMOS CMOS CMOS Z 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 sn2845 2845fs W LTC2845 SWITCHI G TI E WAVEFOR S 3V D 0V VO B–A –VO A VO B t SKEW t SKEW 2845 F05 1.5V t PLH 50% tr 90% 10% f = 1MHz : t r ≤ 10ns : t f ≤ 10ns 1/2 VO Figure 5. V.11 Driver Propagation Delays VOD2 B–A –VOD2 VOH R VOL 0V t PLH 1.65V Figure 6. V.11 Receiver Propagation Delays 3V D 0V VO A –VO tf 1.5V t PHL 3V 0V –3V –3V tr 0V 1.5V t PLH 3V 2845 F07 Figure 7. V.10, V.28 Driver Propagation Delays VIH A VIL VOH R VOL RECEIVER THRESHOLD t PHL 1.65V RECEIVER THRESHOLD t PLH 1.65V 2845 F08 Figure 8. V.10, V.28 Receiver Propagation Delays W W U 1.5V t PHL VDIFF = V(B) – V(A) 90% tf 50% 10% f = 1MHz : t r ≤ 10ns : t f ≤ 10ns INPUT 0V t PHL OUTPUT 1.65V 2845 F06 sn2845 2845fs 9 LTC2845 APPLICATIONS INFORMATION Overview The LTC2846/LTC2845 or LTC2847/LTC2845 form the core of a complete software-selectable DTE or DCE interface port that supports the RS232, RS449, EIA530, EIA530A, V.35, V.36 or X.21 protocols. Cable termination is provided on-chip, eliminating the need for discrete designs. A complete DCE-to-DTE interface operating in EIA530 mode is shown in Figure 9. The LTC2846 of each port is used to generate the clock and data signals. The LTC2845 is used to generate the control signals along with LL (Local Loop-Back), RL (Remote Loop-Back), TM (Test Mode) and RI (Ring Indicate). Cable termination is used only for the clock and data signals because they must support V.11 cable termination. The control signals do not need any external resistors. DCE LTC2846 TXD 103Ω R3 SERIAL CONTROLLER TXD DTE SERIAL CONTROLLER TXD D1 LTC2846 SCTE D2 D3 TXC R1 103Ω RXC R2 103Ω RXD R3 103Ω LTC2845 RTS D1 RTS DTR D2 D3 DCD R1 DSR R2 CTS R3 LL TM RI RL D4 R4 R5 D5 Figure 9. Complete Multiprotocol Interface in EIA530 Mode sn2845 2845fs 10 U W U U SCTE 103Ω R2 SCTE R1 TXC D3 TXC RXC D2 RXC RXD D1 RXD LTC2845 R3 RTS DTR R2 DTR R1 DCD D3 DCD DSR D2 DSR CTS LL TM RI RL D1 CTS R4 D4 D5 R5 LL TM RI RL 2845 F09 LTC2845 APPLICATIONS INFORMATION Mode Selection The interface protocol is selected using the mode select pins M0, M1 and M2 (see the Mode Selection table). For example, if the port is configured as a V.35 interface, the mode selection pins should be M2 = 1, M1 = 0, M0 = 0. For the control signals, the drivers and receivers will operate in V.28 (RS232) electrical mode. For the clock and data signals, the drivers and receivers will operate in V.35 electrical mode. The DCE/DTE pin will configure the port for DCE mode when high, and DTE when low. The interface protocol may be selected simply by plugging the appropriate interface cable into the connector. The mode pins are routed to the connector and are left unconnected (1) or wired to ground (0) in the cable as shown in Figure 10. The internal pull-up current sources will ensure a binary 1 when a pin is left unconnected and that the LTC2846/ LTC2845 enters the no-cable mode when the cable is removed. In the no-cable mode the LTC2846/LTC2845 supply current drops to less than 1000µA and all driver outputs are forced into a high impedance state. The mode selection may also be accomplished by using jumpers to connect the mode pins to ground or VIN. (DATA) M0 LTC2846 M1 M2 DCE/DTE NC NC DCE/DTE M2 M1 LTC2845 M0 D4ENB R4EN (DATA) 3.3k Figure 10. Single Port DCE V.35 Mode Selection in the Cable sn2845 2845fs U W U U Cable Termination Traditional implementations have included switching resistors with expensive relays, or required the user to change termination modules every time the interface standard has changed. Custom cables have been used with the termination in the cable head or separate terminations are built on the board and a custom cable routes the signals to the appropriate termination. Switching the termination with FETs is difficult because the FETs must remain off even though the signal voltage is beyond the supply voltage for the FET drivers or the power is off. Using the LTC2846/LTC2845 solves the cable termination switching problem. Via software control, appropriate termination for the V.10 (RS423), V.11 (RS422), V.28 (RS232) and V.35 electrical protocols is chosen. V.10 (RS423) Interface A typical V.10 unbalanced interface is shown in Figure 11. A V.10 single-ended generator output A with ground C is connected to a differential receiver with inputs A' connected to A, and input C' connected to the signal return ground C. Usually, no cable termination is required for V.10 interfaces, but the receiver inputs must be compliant with the impedance curve shown in Figure 12. CONNECTOR VIN CABLE 2845 F10 11 LTC2845 APPLICATIONS INFORMATION The V.10 receiver configuration in the LTC2845 is shown in Figure 13. In V.10 mode switch S3 inside the LTC2845 is turned off. The noninverting input is disconnected inside the LTC2845 receiver and connected to ground.The cable termination is then the 30k input impedance to ground of the LTC2845 V.10 receiver. GENERATOR BALANCED INTERCONNECTING CABLE LOAD CABLE TERMINATION A A' RECEIVER C C' Figure 11. Typical V.10 Interface IZ –10V –3V VZ 3V 10V –3.25mA Figure 12. V.10 Receiver Input Impedance A' R1 51.5Ω LTC2845 R8 6k S3 R5 20k R6 10k RECEIVER R2 51.5Ω R4 20k R7 10k S1 S2 R3 124Ω R8 6k S3 R5 20k R6 10k RECEIVER LTC2846 A' B' C' R4 20k R7 10k GND 2845 F13 Figure 13. V.10 Receiver Configuration 12 U W U U V.11 (RS422) Interface A typical V.11 balanced interface is shown in Figure 14. A V.11 differential generator with outputs A and B with ground C is connected to a differential receiver with ground C', inputs A' connected to A, B' connected to B. The V.11 interface has a differential termination at the receiver end that has a minimum value of 100Ω. The termination resistor is optional in the V.11 specification, but for the high speed clock and data lines, the termination is required to prevent reflections from corrupting the data. The receiver inputs must also be compliant with the impedance curve shown in Figure 12. In V.11 mode, all switches are off except S1 of the LTC2846’s receivers which connects a 103Ω differential termination impedance to the cable as shown in Figure 151. The LTC2845 only handles control signals, so no termination other than its V.11 receivers’ 30k input impedance is necessary. GENERATOR BALANCED INTERCONNECTING CABLE LOAD CABLE TERMINATION A A' 100Ω MIN RECEIVER 2845 F11 3.25mA B C B' C' 2845 F14 2845 F12 Figure 14. Typical V.11 Interface B' C' GND 2845 F15 Figure 15. V.11 Receiver Configuration 1Actually, there is no switch S1 in receivers R2 and R3. However, for simplicity, all termination networks on the LTC2846 can be treated identically if it is assumed that an S1 switch exists and is always closed on the R2 and R3 receivers. sn2845 2845fs LTC2845 APPLICATIONS INFORMATION V.28 (RS232) Interface A typical V.28 unbalanced interface is shown in Figure 16. A V.28 single-ended generator output A with ground C is connected to a single-ended receiver with input A' connected to A, ground C' connected via the signal return ground C. In V.28 mode, all switches are off except S3 inside the LTC2846/LTC2845 which connects a 6k (R8) impedance to ground in parallel with 20k (R5) plus 10k (R6) for a combined impedance of 5k as shown in Figure 17. The noninverting input is disconnected inside the LTC2846/ LTC2845 receiver and connected to a TTL level reference voltage for a 1.4V receiver trip point. V.35 Interface A typical V.35 balanced interface is shown in Figure 18. A V.35 differential generator with outputs A and B with ground C is connected to a differential receiver with ground C', inputs A' connected to A, B' connected to B. The V.35 interface requires a T or delta network termination at the receiver end and the generator end. The receiver differential impedance measured at the connector must be 100Ω ±10Ω, and the impedance between shorted terminals (A' and B') and ground C' must be 150Ω ±15Ω. In V.35 mode, both switches S1 and S2 inside the LTC2846 are on, connecting the T network impedance as shown in Figure 19. The 30k input impedance of the receiver is placed in parallel with the T network termination, but does not affect the overall input impedance significantly. The generator differential impedance must be 50Ω to 150Ω and the impedance between shorted terminals (A and B) and ground C must be 150Ω ±15Ω. For the generator termination, switches S1 and S2 are both on as shown in Figure 20. BALANCED INTERCONNECTING CABLE GENERATOR BALANCED INTERCONNECTING CABLE LOAD CABLE TERMINATION RECEIVER A A' C C' Figure 16. Typical V.28 Interface A' R8 6k S3 R5 20k R6 10k RECEIVER A' LTC2845 B' C' R4 20k R7 10k B' GND 2845 F17 Figure 17. V.28 Receiver Configuration U W U U GENERATOR LOAD CABLE TERMINATION RECEIVER A 50Ω 125Ω A' 125Ω 50Ω 50Ω B 2845 F16 50Ω B' C' 2845 F18 C Figure 18. Typical V.35 Interface LTC2846 R1 51.5Ω S1 S2 R2 51.5Ω R8 6k S3 R5 20k R6 10k R3 124Ω RECEIVER R4 20k R7 10k C' GND 2845 F19 Figure 19. V.35 Receiver Configuration sn2845 2845fs 13 LTC2845 APPLICATIONS INFORMATION LTC2846 51.5Ω V.35 DRIVER 124Ω S1 S2 51.5Ω B C 2845 F20 A Figure 20. V.35 Driver No-Cable Mode The no-cable mode (M0 = M1 = M2 = D4ENB = 1, R4EN = 0) is intended for the case when the cable is disconnected from the connector. The bias circuitry, drivers and receivers are turned off, the driver outputs are forced into a high impedance state, and the supply current drops to less than 700µA. LTC2846 and LTC2847 Supplies The LTC2846 and LTC2847 use an internal capacitive charge pump to generate VDD and VEE as shown in Figure 21. A voltage doubler generates about 8V on VDD and a voltage inverter generates about – 7.5V for VEE. Three 1µF surface mounted tantalum or ceramic capacitors are required for C1, C2 and C3. The VEE capacitor C4 should be a minimum of 3.3µF. All capacitors are 16V and should be placed as close as possible to the LTC2846 to reduce EMI. The LTC2846 has an internal boost switching regulator which generates a 5V output from the 3.3V supply as shown in Figure 22. The 5V VCC supplies its internal charge pump and transceivers as well as its companion chip. The LTC2847 requires an external 5V supply. Receiver Fail-Safe All LTC2846/LTC2845 receivers feature fail-safe operation in all modes. If the receiver inputs are left floating or shorted together by a termination resistor, the receiver output will always be forced to a logic high. C3 1µF C1 1µF VDD C1+ C1– VCC C5 10µF 2845 F21 C2 + LTC2846 OR LTC2847 C2 – VEE GND C2 1µF C4 3.3µF 5V Figure 21. Charge Pump 14 U + W U U DTE vs DCE Operation The DCE/DTE pin acts as an enable for Driver 3/Receiver 1 in the LTC2846, and Driver 3/Receiver 1 in the LTC2845. The LTC2846/LTC2845 can be configured for either DTE or DCE operation in one of two ways: a dedicated DTE or DCE port with a connector of appropriate gender, or a port with one connector that can be configured for DTE or DCE operation by rerouting the signals to the LTC2846/LTC2845 using a dedicated DTE cable or dedicated DCE cable. A dedicated DTE port using a DB-25 male connector is shown in Figure 23. The interface mode is selected by logic outputs from the controller or from jumpers to either VIN or GND on the mode select pins. A dedicated DCE port using a DB-25 female connector is shown in Figure 24. A port with one DB-25 connector, can be configured for either DTE or DCE operation is shown in Figure 25. The configuration requires separate cables for proper signal routing in DTE or DCE operation. For example, in DTE mode, the TXD signal is routed to Pins 2 and 14 via Driver 1 in the LTC2846. In DCE mode, Driver 1 now routes the RXD signal to Pins 2 and 14. Compliance Testing The LTC2846/LTC2845 chipset has been tested by TUV Rheinland of North America Inc. and passed the NET1, NET2 and TBR2 requirements. Copies of the test report are available from LTC or TUV Rheinland of North America Inc. The title of the report is Test Report No.TBR2/050101/02 The address of TUV Rheinland of North America Inc. is: TUV Rheinland of North America Inc. 1775, Old Highway 8 NW, Suite 107 St. Paul, MN 55112 Tel. (651) 639-0775 Fax (651) 639-0873 VIN 3.3V C6 10µF VIN L1 5.6µH D1 VCC 5V 480mA R1 13k C5 10 µF R2 4.3k SHDN SW BOOST SWITCHING REGULATOR SHDN FB GND C1,C2: TAIYO YUDEN X5R JMK316BJ106ML D1: ON SEMICONDUCTOR MBR0520 L1: SUMIDA CR43-5R6 2845 F22 Figure 22. LTC2846 Boost Switching Regulator sn2845 2845fs LTC2845 TYPICAL APPLICATIONS VIN 3.3V L1 5.6µH C6 10µF SHDN VDD 8V C3 1µF VCC 5V LTC2846 TXD D1 T D1 MBR0520 R1 13k R2 4.3k C2 1µF C1 1µF CHARGE PUMP VEE –7.5V C4 3.3µF C5 10µF VCC 5V SCTE D2 T D3 T 15 TXC A (114) TXC B RXC A (115) RXC B RXD A (104) RXD B SG SHIELD DB-25 MALE CONNECTOR 4 TXC R1 RXC R2 T RXD M0 M1 M2 R3 T VIN 3.3V DCE/DTE C7 1µF VCC C8 1µF RTS VDD D1 VEE GND DTR D2 D3 LTC2845 DCD R1 R2 8 10 6 DSR 22 5 CTS LL RI R3 D4 R4 13 18 * TM RL M0 M1 M2 M0 M1 M2 R5 D5 VIN D4ENB R4EN NC C10 1µF VIN 3.3V DCE/DTE Figure 23. Controller-Selectable Multiprotocol DTE Port with DB-25 Connector sn2845 2845fs + U BOOST SWITCHING REGULATOR 2 TXD A (103) 14 TXD B 24 SCTE A (113) 11 SCTE B 12 17 9 3 16 7 1 C9 1µF 19 20 23 RTS A (105) RTS B DTR A (108) DTR B DCD A (109) DCD B DSR A (107) DSR B CTS A (106) CTS B LL (141) RI (125) 25 21 TM (142) RL (140) *OPTIONAL 2845 F23 15 LTC2845 TYPICAL APPLICATIONS VIN 3.3V L1 5.6µH C6 10µF SHDN VDD 8V C3 1µF VCC 5V LTC2846 RXD D1 T D1 MBR0520 R1 13k R2 4.3k C2 1µF C1 1µF CHARGE PUMP VEE –7.5V C4 3.3µF C5 10µF VCC 5V RXC D2 T D3 T 15 TXC A (114) TXC B SCTE A (113) SCTE B TXD A (103) TXD B SG (102) SHIELD (101) DB-25 FEMALE CONNECTOR 5 TXC R1 SCTE R2 T TXD M0 M1 M2 NC R3 T VIN 3.3V DCE/DTE C7 1µF VCC C8 1µF CTS VDD D1 VEE GND DSR D2 D3 LTC2845 DCD R1 R2 8 10 20 DTR 23 4 RTS RI LL R3 D4 R4 19 * 18 RL TM M0 M1 M2 NC M0 M1 M2 R5 D5 VIN D4ENB R4EN NC C10 1µF VIN 3.3V DCE/DTE Figure 24. Controller-Selectable DCE Port with DB-25 Connector sn2845 2845fs 16 + U BOOST SWITCHING REGULATOR 2 RXD A (104) 14 RXD B 24 RXC A (115)B 11 RXC B 12 24 11 2 14 7 1 C9 1µF 13 6 22 CTS A (106) CTS B DSR A (107) DSR B DCD A (109) DCD B DTR A (108) DTR B RTS A (105) RTS B RI (125) LL (141) 21 25 RL (140) TM (142) *OPTIONAL 2845 F24 LTC2845 TYPICAL APPLICATIONS VIN 3.3V L1 5.6µH C6 10µF SHDN VDD 8V C3 1µF VCC 5V LTC2846 DTE_TXD/DCE_RXD D1 T D1 MBR0520 R1 13k R2 4.3k C2 1µF C1 1µF CHARGE PUMP VEE –7.5V C4 3.3µF DTE 2 14 24 DTE_SCTE/DCE_RXC D2 T 11 TXD A TXD B SCTE A SCTE B DCE RXD A RXD B RXC A RXC B C5 10µF VCC 5V D3 T 15 TXC A TXC B RXC A RXC B RXD A RXD B SG SHIELD DB-25 CONNECTOR 4 TXC A TXC B SCTE A SCTE B TXD A TXD B DTE_TXC/DCE_TXC R1 DTE_RXC/DCE_SCTE R2 T DTE_RXD/DCE_TXD M0 M1 M2 R3 T VIN 3.3V DCE/DTE C7 1µF VCC C8 1µF DTE_RTS/DCE_CTS VDD D1 VEE GND DTE_DTR/DCE_DSR D2 D3 LTC2845 DTE_DCD/DCE_DCD R1 R2 8 10 6 DTE_DSR/DCE_DTR 22 5 DTE_CTS/DCE_RTS DTE_LL/DCE_RI DTE_RI/DCE_LL R3 D4 R4 13 18 * DTE_TM/DCE_RL DTE_RL/DCE_TM M0 M1 M2 DCE/DTE M0 M1 M2 R5 D5 VIN D4ENB R4EN NC C10 1µF VIN 3.3V DCE/DTE Figure 25. Controller-Selectable Multiprotocol DTE/DCE Port with DB-25 Connector sn2845 2845fs + U BOOST SWITCHING REGULATOR 12 17 9 3 16 7 1 C9 1µF 19 20 23 RTS A RTS B DTR A DTR B CTS A CTS B DSR A DSR B DCD A DCD B DSR A DSR B CTS A CTS B LL RI DCD A DCD B DTR A DTR B RTS A RTS B RI LL 25 21 TM RL RL TM *OPTIONAL 2845 F25 17 LTC2845 PACKAGE DESCRIPTION G Package 36-Lead Plastic SSOP (5.3mm) (Reference LTC DWG # 05-08-1640) 12.50 – 13.10* (.492 – .516) 1.25 ± 0.12 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19 7.8 – 8.2 0.42 ± 0.03 RECOMMENDED SOLDER PAD LAYOUT 5.00 – 5.60** (.197 – .221) 0.09 – 0.25 (.0035 – .010) 0.55 – 0.95 (.022 – .037) NOTE: 1. CONTROLLING DIMENSION: MILLIMETERS MILLIMETERS 2. DIMENSIONS ARE IN (INCHES) 3. DRAWING NOT TO SCALE *DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED .152mm (.006") PER SIDE **DIMENSIONS DO NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED .254mm (.010") PER SIDE 18 U 5.3 – 5.7 7.40 – 8.20 (.291 – .323) 0.65 BSC 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 2.0 (.079) 0 ° – 8° 0.65 (.0256) BSC 0.22 – 0.38 (.009 – .015) 0.05 (.002) G36 SSOP 0802 sn2845 2845fs LTC2845 PACKAGE DESCRIPTIO U UHF Package 38-Lead Plastic QFN (5mm × 7mm) (Reference LTC DWG # 05-08-1701) 0.70 ± 0.05 PACKAGE OUTLINE 0.25 ± 0.05 0.50 BSC 5.20 ± 0.05 (2 SIDES) 6.10 ± 0.05 (2 SIDES) 7.50 ± 0.05 (2 SIDES) RECOMMENDED SOLDER PAD LAYOUT 5.00 ± 0.10 (2 SIDES) 0.75 ± 0.05 0.00 – 0.05 3.15 ± 0.10 (2 SIDES) 0.435 0.18 0.18 37 38 1 2 0.23 5.15 ± 0.10 (2 SIDES) 0.40 ± 0.10 0.200 REF 0.25 ± 0.05 0.75 ± 0.05 0.200 REF 0.00 – 0.05 0.50 BSC R = 0.115 TYP (UH) QFN 0303 5.50 ± 0.05 (2 SIDES) 4.10 ± 0.05 (2 SIDES) 3.20 ± 0.05 (2 SIDES) PIN 1 TOP MARK (SEE NOTE 6) 7.00 ± 0.10 (2 SIDES) BOTTOM VIEW—EXPOSED PAD NOTE: 1. DRAWING CONFORMS TO JEDEC PACKAGE OUTLINE M0-220 VARIATION WHKD 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.20mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE sn2845 2845fs Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 19 LTC2845 TYPICAL APPLICATIO RL TM RI LL CTS DSR DTE or DCE Multiprotocol Serial Interface with DB-25 Connector DCD DTR RTS RXD RXC TXC SCTE TXD D5 R5 R4 D4 R3 R2 21 RL A (140) 25 TM A (142) * RI A (125) 18 13 5 LL A (141) CTS B CTS A (106) 10 8 DSR B DSR A (109) RELATED PARTS PART NUMBER LTC1321 LTC1334 LTC1343 LTC1344A LTC1345 LTC1346A LTC1543 LTC1544 LTC1545 LTC1546 LTC2844 LTC2846 DESCRIPTION Dual RS232/RS485 Transceiver Single 5V RS232/RS485 Multiprotocol Transceiver Software-Selectable Multiprotocol Transceiver Software-Selectable Cable Terminator Single Supply V.35 Transceiver Dual Supply V.35 Transceiver Software-Selectable Multiprotocol Transceiver Software-Selectable Multiprotocol Transceiver Software-Selectable Multiprotocol Transceiver Software-Selectable Multiprotocol Transceiver 3.3V Software-Selectable Multiprotocol Transceiver 3.3V Software-Selectable Multiprotocol Transceiver LTC2847 Software-Selectable Multiprotocol Transceiver with 3.3V Digital Interface 20 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 q FAX: (408) 434-0507 q U LTC2845 D3 R1 D2 D1 R3 R2 R1 LTC2846 D3 D2 D1 T T T T T 22 6 DCD B DCD A (107) 23 20 19 4 DTR B DTR A (108) RTS B RTS A (105) SHIELD (101) 1 SG (102) 7 16 RXD B 3 RXD A (104) 9 RXC B 17 RXC A (115) 12 TXC B TXC A (114) 15 11 SCTE B SCTE A (113) 24 14 TXD B 2 TXD A (103) *OPTIONAL DB-25 CONNECTOR 2845 TA01 COMMENTS Two RS232 Driver/Receiver Pairs or Two RS485 Driver/Receiver Pairs Two RS232 Driver/Receiver or Four RS232 Driver/Receiver Pairs 4-Driver/4-Receiver for Data and Clock Signals Perfect for Terminating the LTC1543 (Not Needed with LTC1546) 3-Driver/3-Receiver for Data and Clock Signals 3-Driver/3-Receiver for Data and Clock Signals Terminated with LTC1344A for Data and Clock Signals, Companion to LTC1544 or LTC1545 for Control Signals Companion to LTC1546 or LTC1543 for Control Signals Including LL 5-Driver/5-Receiver Companion to LTC1546 or LTC1543 for Control Signals Including LL, TM and RL 3-Driver/3-Receiver with Termination for Data and Clock Signals 3.3V Supply, 4-Driver/4-Receiver Companion to LTC2846 for Control Signals Including LL 3.3V Supply, 3-Driver/3-Receiver with Termination for Data and Clock Signals, Generates the Required 5V and ±8V Supplies for LTC2846 and Companion Parts 3-Driver/3-Receiver with Termination for Data and Clock Signals. Seperate Supply for Digital Interface Works Down to 3.3V sn2845 2845fs LT/TP 0703 1K • PRINTED IN USA www.linear.com © LINEAR TECHNOLOGY CORPORATION 2002