MAX145

19-1387; Rev 0; 11/98 +2.7V, Low-Power, 2-Channel, 108ksps, Serial 12-Bit ADCs in 8-Pin µMAX General Description The MAX144/MAX145 low-power, 12-bit analog-todigital converters (ADCs) are available in 8-pin µMAX and DIP packages. Both devices operate with a single +2.7V to +5.25V supply and feature a 7.4µs successive-approximation ADC, automatic power-down, fast wake-up (2.5µs), an on-chip clock, and a high-speed, 3-wire serial interface. Power consumption is only 3.2mW (VDD = +3.6V) at the maximum sampling rate of 108ksps. At slower throughput rates, the automatic shutdown (0.2µA) further reduces power consumption. The MAX144 provides 2-channel, single-ended operation and accepts input signals from 0 to VREF. The MAX145 accepts pseudo-differential inputs ranging from 0 to V REF . An external clock accesses datathrough the 3-wire serial interface, which is SPI™, QSPI™, and MICROWIRE™-compatible. Excellent dynamic performance and low power, combined with ease of use and small package size, make these converters ideal for battery-powered and dataacquisition applications, or for other circuits with demanding power-consumption and space requirements. For pin-compatible 10-bit ADCs, see the MAX157 and MAX159. Features o Single-Supply Operation (+2.7V to +5.25V) o Two Single-Ended Channels (MAX144) One Pseudo-Differential Channel (MAX145) o Low Power 0.9mA (108ksps, +3V Supply) 100µA (10ksps, +3V Supply) 10µA (1ksps, +3V Supply) 0.2µA (Power-Down Mode) o Internal Track/Hold o 108...