TXD A (103) TXD B SCTE A (113) SCTE B TXC A (114) TXC B RXC A (115) RXC B RXD A (104) RXD B SG (102) SHIELD (101) RTS A (105) RTS B DTR A (108) DTR B DCD A (107) DCD B DSR A (109) DSR B CTS A (106) CTS B LL A (141) LTC1344A Software-Selectable Cable Terminator DESCRIPTION FEATURES n Software-Selectable Cable Termination for: The LTC 1344A features six software-selectable RS232 (V.28) multiprotocol cable terminators. Each terminator can be RS423 (V.10) configured as an RS422 (V.11) 100W minimum differen- RS422 (V.11) tial load, V.35 T-network load or an open circuit for use RS485 with RS232 (V.28) or RS423 (V.10) transceivers that RS449 provide their own termination. When combined with the EIA530 LTC1543 and LTC1544, the LTC1344A forms a complete EIA530-A software-selectable multiprotocol serial port. A data bus V.35 latch feature allows sharing of the select lines between V.36 multiple interface ports. X.21 The LTC1344A is similar to the LTC1344 except for a n Outputs Wont Load the Line with Power Off difference in the Mode Selection table. U The LTC1344A is available in a 24-lead SSOP. APPLICATIONS n Data Networking n CSU and DSU n Data Routers , LTC and LT are registered trademarks of Linear Technology Corporation. TYPICAL APPLICATION DTE or DCE Multiprotocol Serial Interface with DB-25 Connector LL CTS DSR DCD DTR RTS TXC SCTE TXD RXD RXC Daisy-Chained Control Outputs LTC1544 LTC1543 D3 D2 D1 D4 D3 D2 D1 R3 R2 R1 R4 R3 R2 R1 LTC1344A 18 13 5 10 8 22 623 20 19 4 1 7 16 3 9 17 12 15 11 24 14 2 DB-25 CONNECTOR 1344A TA01 1 U ULTC1344A ABSOLUTE MAXIMUM RATINGS PACKAGE/ORDER I FOR ATIO (Note 1) TOP VIEW Positive Supply Voltage (V )................................... 7V CC ORDER PART 1 24 M1 M0 Negative Supply Voltage (V ) ........................... 13.2V NUMBER EE 2 23 M2 V EE Input Voltage LTC1344ACG 3 22 DCE/DTE R1C (Logic Inputs) .................... (V 0.3V) to (V + 0.3V) EE CC LTC1344AIG 4 21 LATCH R1B Input Voltage (Load Inputs) .................................. 18V 5 20 R6B R1A Power Dissipation.............................................. 600mW 6 19 R6A R2A Operating Temperature Range 7 18 R5A R2B LTC1344AC ............................................ 0 C to 70 C 8 17 R5B R2C LTC1344AI ......................................... 40 C to 85 C 9 16 R4A R3A Storage Temperature Range ................ 65 C to 150 C 10 15 R4B R3B Lead Temperature (Soldering, 10 sec)................. 300 C 11 14 V R3C CC GND 12 13 GND G PACKAGE 24-LEAD PLASTIC SSOP T = 150 C, q = 100 C/W JMAX JA Consult factory for Military grade parts. ELECTRICAL CHARACTERISTICS V = 5V 5%, V = 5V 5%, T = T to T (Notes 2, 3) unless otherwise noted. CC EE A MIN MAX SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS Supplies I Supply Current All Digital Pins = GND or V l 0.4 1.0 mA CC CC Terminator Pins R Differential Mode Impedance All Loads (Figure 1), 2V V 2V (Commercial) l 90 104 110 W V.35 CM Common Mode Impedance All Loads (Figure 2), 2V V 2V (Commercial) l 135 153 165 W CM All Loads (Figure 1), 2V V 2V (Industrial) l 90 104 115 W CM All Loads (Figure 2), 2V V 2V (Industrial) l 130 153 170 W CM R Differential Mode Impedance All Loads (Figure 1), V = 0V (Commercial) l 100 104 110 W V.11 CM All Loads (Figure 1), 7V V 7V (Commercial) 100 104 W CM All Loads (Figure 1), V = 0V (Industrial) l 95 104 115 W CM All Loads (Figure 1), 7V V 7V (Industrial) 100 104 W CM I High Impedance Leakage Current All Loads, 7V V 7V l 1 50 m A LEAK CM Logic Inputs V Input High Voltage All Logic Input Pins l2V IH V Input Low Voltage All Logic Input Pins l 0.8 V IL I Input Current All Logic Input Pins l 10 m A IN The l denotes specifications which apply over the full operating Note 2: All currents into device pins are positive all currents out of device temperature range. pins are negative. All voltages are reference to ground unless otherwise specified. Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 3: All typicals are given at V = 5V, V = 5V, T = 25 C. CC EE A 2 U U WWW WU