The DS87C550 is a CMOS 8051‑compatible microcontroller offering up to 33 MHz clock speed, three 16‑bit timer/counters, two full‑duplex serial ports, eight 10‑bit ADC channels and four 8‑bit PWM channels. It provides 8 KB of EPROM, 1 KB of on‑chip SRAM, 256 bytes of scratchpad RAM and 55 I/O pins, with selectable ROM size from 0 to 8 KB.
The device is available in 68‑pin PLCC, 80‑pin PQFP and 68‑pin windowed CLCC packages, supports power‑fail reset, watchdog timer and multiple power‑saving modes, and includes EMI reduction features such as ALEOFF.
| Package Types | 68‑Pin PLCC, 80‑Pin PQFP, 68‑Pin Windowed CLCC |
|---|---|
| ADC Channels | 8 channels, 10‑bit resolution |
| PWM Channels | 4 channels, 8‑bit (cascadable to 16‑bit) |
| I/O Pins | 55 pins |
| Timer/Counters | Three 16‑bit timer/counters |
| Serial Ports | Two full‑duplex hardware serial ports |
It is offered in 68‑Pin PLCC, 80‑Pin PQFP and 68‑Pin Windowed CLCC packages.
The microcontroller includes eight 10‑bit ADC channels.