LTC1091/LTC1092 LTC1093/LTC1094 WUTYPICAL PERFOR A CE CHCARA TERISTICSLTC1092/LTC1093/LTC1094LTC1093/LTC1094 Input ChannelReference Current vs TemperatureLeakage Current vs Temperature 0.6 1000 VREF = 5V 900 GUARANTEED 0.5 800 700 0.4 600 0.3 500 400 0.2 300 REFERENCE CURRENT (mA) ON-CHANNEL 200 0.1 OFF-CHANNEL 100 INPUT CHANNEL LEAKAGE CURRENT (nA) 0 0 –50 –25 0 25 50 75 100 125 –50 –25 0 25 50 75 100 125 AMBIENT TEMPERATURE (°C) AMBIENT TEMPERATURE (°C) 1091/2/3/4 G28 1091/2/3/4 G29 UUUPI FU CTIO SLTC1091/LTC1092CS (Pin 1): Chip Select Input. A logic low on this input VCC (Pin 8 )(LTC1092): Positive Supply Voltage. This pin enables the LTC1091/LTC1092. provides power to the A/D converter. It must be kept free of noise and ripple by bypassing directly to the analog CH0, CH1/+ IN, – IN (Pins 2, 3): Analog Inputs. These ground plane. inputs must be free of noise with respect to GND. GND (Pin 4): Analog Ground. GND should be tied directly LTC1093/LTC1094 to an analog ground plane. CH0 to CH5/CH0 to CH7 (Pins 1 to 6/Pins 1 to 8): Analog D Inputs. The analog inputs must be free of noise with IN (Pin 5)(LTC1091): Digital Data Input. The multiplexer address is shifted into this input. respect to AGND. VCOM (Pin 7/Pin 9): Common. The common pin defines the REF (Pin 5)(LTC1092): Reference Input. The reference input defines the span of the A/D converter and must be zero reference point for all single-ended inputs. It must be kept free of noise with respect to AGND. free of noise and is usually tied to the analog ground plane. DDGND (Pin 8/Pin 10): Digital Ground. This is the ground OUT (Pin 6): Digital Data Output. The A/D conversion result is shifted out of this output. for the internal logic. Tie to the ground plane. CLK (Pin 7): Shift Clock. This clock synchronizes the serial V – (Pin 9/Pin 11): Negative Supply. Tie V – to most data transfer. negative potential in the circuit. (Ground in single supply applications.) VCC(VREF)(Pin 8)(LTC1091): Positive Supply and Refer- ence Voltage. This pin provides power and defines the AGND (Pin 10/Pin 12): Analog Ground. AGND should be span of the A/D converter. It must be kept free of noise and tied directly to the analog ground plane. ripple by bypassing directly to the analog ground plane. 8