The AD7730/AD7730L Bridge Transducer ADC is a complete analog front end for weigh-scale and pressure measurement applications. The device accepts low-level signals directly from a transducer and outputs a serial digital word. The input signal is applied to a proprietary pro-grammable gain front end based around an analog modulator.
The AD7730 family is a 24‑bit sigma‑delta ADC designed for bridge‑transducer applications such as weigh scales and pressure measurement. It offers programmable gain front‑ends, on‑chip DAC for offset/TARE removal, and multiple filter modes including FASTStep™ and FIR filtering.
The device operates from a single +5 V supply, supports a range of unipolar and bipolar input spans, and provides serial interfaces compatible with microcontrollers and DSPs. Packages include 24‑pin DIP, 24‑lead SOIC and 24‑lead TSSOP, with detailed electrical specifications and timing characteristics listed throughout the document.
| Resolution | 230,000 counts (peak‑to‑peak) |
|---|---|
| Offset Drift | 5 nV/°C (typ) |
| Gain Drift | 2 ppm/°C (max) |
| Line Frequency Rejection | >150 dB |
| Power Supply Rejection | 120 dB typ |
| Common‑Mode Rejection | 120 dB min (DC) |
| Analog Input DC Bias Current | 50 nA max |
| Supply Voltage (AVpp) | +4.75 to +5.25 V |
The AD7730 provides a 230,000‑count (peak‑to‑peak) resolution.
Offset drift is specified as 5 nV/°C typical.
It operates from a single +5 V supply, with AVpp allowed from +4.75 V to +5.25 V.
The AD7730 is offered in 24‑pin plastic DIP, 24‑lead SOIC, and 24‑lead TSSOP packages; the AD7730L is in SOIC and TSSOP.