12-bit dual-slope ADC in a 40-pin DIP
The ICL7109CPL+ is a 12-bit integrating ADC built on a dual-slope architecture, sampling at 30 conversions per second. The differential input rejects common-mode noise, and the parallel data interface makes it straightforward to read into a microcontroller or latch without a serial clock. It runs on ±5 V supplies for both the analog and digital sections, and requires an external voltage reference — typical for ratiometric measurements where the reference tracks the sensor excitation.
Through-hole package for repair and prototyping
Housed in a 40-lead PDIP (0.600" wide body, 15.24 mm row spacing), this part is through-hole only — no surface-mount variant. The commercial temperature range (0°C to 70°C) covers most benchtop instruments, panel meters, and industrial controllers that live indoors. If your application sees -40°C, this isn't the grade.