The Intersil HI7190 is a 24-bit high-precision Sigma Delta A/D converter that operates from ±5V supplies. The signal and reference inputs are fully differential for maximum flexibility and performance. An internal Programmable Gain Instrumentation Amplifier (PGIA) provides input gains from 1 to 128, eliminating the need for external pre-amplifiers. The on-demand converter auto-calibrate function is capable of removing offset and gain errors existing in external and internal circuitry. The on-board user programmable digital filter provides over 120dB of 60/50Hz noise rejection and allows fine tuning of resolution and conversion speed over a wide dynamic range. The HI7190 and HI7191 are functionally the same device, but the HI7190 has tighter linearity specifications. The HI7190 contains a serial I/O port and is compatible with most synchronous transfer formats, including both the Motorola 6805/11 series SPI and Intel 8051 series SSR protocols. A sophisticated set of commands gives the user control over calibration, PGIA gain, device selection, etc.
The HI7190 is a monolithic 24‑bit sigma‑delta A/D converter that operates from a +5 V supply. It offers fully differential inputs, an internal programmable‑gain instrumentation amplifier (PGIA) with gains from 1 to 128, and a serial I/O port compatible with SPI and SSR protocols. On‑demand auto‑calibration removes offset and gain errors, while the on‑chip digital filter gives over 120 dB line‑noise rejection.
The datasheet includes ordering information for PDIP and SOIC packages, a functional block diagram, typical application schematics, absolute maximum ratings, detailed electrical specifications, pin descriptions, timing diagrams, and noise performance tables. Typical applications listed are process control, industrial weight scales, laboratory instrumentation, and seismic monitoring.
| Resolution | 22‑Bit |
|---|---|
| Integral Non‑Linearity (INL) | 0.0007 % typ |
| Full‑Scale Input Range | 20 mV to +2.5 V |
| PGIA Gain | 1 to 128 |
| Serial Interface | SPI compatible (Motorola 6805/11, Intel 8051 SSR) |
| Line‑Noise Rejection | 120 dB at 50/60 Hz |
| Supply Voltage | +5 V (AVpp) |
| Supply Current (Active) | 15 mA typical |
The device accepts a full‑scale input range of 20 mV to +2.5 V.
The HI7190 is offered in 20‑lead PDIP and 20‑lead SOIC packages, with part numbers such as HI7190IP, HI7190IPZ, HI71901B, and HI71901BZ.
It provides an on‑demand auto‑calibrate function and on‑chip calibration registers that allow reading and writing of calibration data.
The device’s serial I/O port is compatible with Motorola 6805/11 SPI and Intel 8051 SSR protocols.