ADS7870

ADS7870 SBAS124C − DECEMBER 1999 − REVISED DECEMBER 2005 12ĆBIT, 52ĆkSPS, DATA ACQUISITION SYSTEM WITH ANALOGĆTOĆDIGITAL CONVERTER, MUX, PGA, AND REFERENCE FEATURES D PGA Gains: 1, 2, 4, 5, 8, 10, 16, 20 V/V D Programmable Input (Up to 4-Channel Differential/Up to 8-Channel Single-Ended or Some Combination) D 1.15-V, 2.048-V, or 2.5-V Internal Reference D SPI/DSP Compatible Serial Interface (≤ 20 MHz) D Throughput Rate: 52 kSamples/sec D Error Overload Indicator D Programmable Output 2s Complement/Binary D 2.7-V to 5.5-V Single Supply Operation D 4-Bit Digital I/O Via Serial Interface D Pin-Compatible With ADS7871 D SSOP-28 Package APPLICATIONS D Portable Battery-Powered Systems D Low-Power Instrumentation D Low-Power Control Systems D Smart Sensor Applications DESCRIPTION The ADS7870 (US patents 6140872, 6060874) is a complete low-power data acquisition system on a single chip. It consists of a 4-channel differential/8-channel single-ended multiplexer, precision programmable gain amplifier, 12-bit successive approximation analog-todigital (A/D) converter, and a precision voltage reference. The programmable-gain amplifier provides high input impedance, excellent gain accuracy, good common-mode rejection, and low noise. For many low-level signals, no external amplification or impedance buffering is needed between the signal source and the A/D input. The offset voltage of the PGA is auto-zeroed. Gains of 1, 2, 4, 5, 8, 10, 16, and 20 V/V allow signals as low as 125 mV to pro...