LTC1391 8-Channel Analog Multiplexer with Cascadable Serial Interface UFEATURESDESCRIPTIO ■ Low RON: 45 Ω The LTC ®1391 is a high performance CMOS 8-to-1 analog ■ Single 2.7V to ± 5V Supply Operation multiplexer. It features a serial digital interface that allows ■ Low Charge Injection several LTC1391s to be daisy-chained together, increas- ■ Serial Digital Interface ing the number of MUX channels available using a single ■ Analog Inputs May Extend to Supply Rails digital port. ■ Low Leakage: ±5nA Max The LTC1391 features a typical RON of 45Ω, a typical ■ Guaranteed Break-Before-Make switch leakage of 50pA and guaranteed break-before- ■ TTL/CMOS Compatible for All Digital Inputs make operation. Charge injection is ±10pC maximum. All ■ Cascadable to Allow Additional Channels digital inputs are TTL and CMOS compatible when oper- ■ Can Be Used as a Demultiplexer ated from single or dual supplies. The inputs can with- U stand 100mA fault current. APPLICATIO S The LTC1391 is available in 16-pin PDIP, SSOP and ■ Data Acquisition Systems narrow SO packages. For applications requiring 2-way ■ Communication Systems serial data transmission, see the LTC1390 data sheet. ■ Signal Multiplexing/Demultiplexing , LTC and LT are registered trademarks of Linear Technology Corporation. UTYPICAL APPLICATIOOn-Resistance vs3V, 8-Channel 12-Bit ADCAnalog Input Voltage 3V 300 0.1µF OPTIONAL A/D 1µF T 1 16 1 8 A = 25°C S0 V+ INPUT FILTER V V REF CC 250 2 15 2 7 S1 D +IN CLK V+ = 2.7V ) 3 14 3 LTC1285 6 Ω V – = 0V S2 V – –IN D 200 OUT 4 13 4 5 ANALOG S3 DOUT GND CS/SHDN INPUTS 5 LTC1391 12 150 S4 DIN 6 11 S5 CS 100 7 10 ON-RESISTANCE ( S6 CLK V+ = 5V 8 9 S7 GND 50 V – = –5V DATA IN 0–5 –4 –3 –2 –1 0 1 2 3 4 5 SERIAL INTERFACE CLK ANALOG INPUT VOLTAGE (V) TO MUX AND ADC CS 1391 TA02 DATA OUT 1391 TA01 sn1391 1391fas 1