SGM52421R8A

The SGM52421R8/SGM52421R8A are high-precision, low power, low noise integrated analog front end. They integrate a 24-bit Σ-Δ ADC, supporting 8 differential inputs or 15 single-ended/pseudo-differential inputs, plus an on-chip low-gain amplifier for small-signal acquisition. 

The device features three power modes to balance power draw, output data rate, RMS noise, and alongside multiple configurable filters. At 25SPS single-cycle settling, it provides over 80dB rejection for 50Hz and 60Hz interference at low ODRs. 

The built-in modules include a precision bandgap reference (compatible with the external differential references), programmable excitation and burnout current sources, and a bias voltage generator. A low-side power switch disables bridge sensors between conversions to reduce power consumption. 

The integrated channel sequencer supports up to 16 channels including supply and reference monitoring, enabling interleaved conversion and diagnostics. Each channel can be independently configured for gain, filter, ODR, buffer and reference settings. 

The rich diagnostic functions such as CRC and interface verification improve system reliability, while high integration reduces external components, board size, development time and cost. It achieves over 90% SFF (Safe Failure Fraction) complying with IEC 61508 per FMEDA evaluation. 

The major difference between SGM52421R8 and SGM52421R8A is that the SGM52421R8A supports an nRST physical reset pin without the external clock input pin, whereas the SGM52421R8 supports the external clock input pin without the physical reset pin. 

Power supply: analog 2.7V to 3.6V (or dual 1.8V rails), digital 1.8V to 3.6V. Packaged a Green TQFN-5×5-32IL package, operating temperature range: -40℃ to +125℃. Multi-function pins are marked with full names or primary functions in this datasheet.