Analog Devices Inc./Maxim Integrated DS80C323-QCD

Overview

DS80C323-QCD from Maxim Integrated is a high-speed, low-power 80C32-compatible 8-bit microcontroller featuring 4-clock-per-cycle architecture, 18MHz max crystal frequency, 256 bytes on-chip RAM, dual hardware serial ports, and programmable watchdog timer. It operates from 2.7V to 5.5V and is packaged in 44-pin PLCC for industrial control and embedded instrumentation applications.

For engineers reviewing the DS80C323-QCD datasheet, DS80C323-QCD pinout, DS80C323-QCD application, or DS80C323-QCD equivalent, this page delivers verified electrical specs, validated PLCC pin mapping, confirmed low-voltage operation (2.7–5.5V), dual-serial-port timing behavior, and real-world alternatives with documented functional trade-offs.

Technical Context

The DS80C323-QCD implements a redesigned 8051 core eliminating wasted clock cycles - executing most instructions in 4 oscillator clocks versus 12 in legacy 80C32, yielding up to 3× speed improvement at same crystal frequency. Its dual data pointer (DPTR0/DPTR1) enables zero-overhead block memory moves without register save/restore.

It supports variable-speed MOVX access via CKCON register (SFR 8Eh), allowing stretch values 0–7 (2–9 machine cycles) to interface with slow peripherals or legacy RAM. Timers default to 12-clock mode on reset for backward compatibility but can be reconfigured to 4-clock mode for higher resolution.

Key Specifications

Pinout & Package

DS80C323-QCD is housed in a 44-pin Plastic Leaded Chip Carrier (PLCC) package with J-lead geometry, rated for 0°C to +70°C ambient operation and RoHS-compliant (QCD+ variant). Pin 1 is index corner, counterclockwise numbering.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit microcontroller applications.

Compared with DS80C320-QCG+, DS80C323-QCD trades maximum speed for wider voltage range and lower power; compared with AT89C51RD2-RLTUM, it sacrifices integrated Flash for superior peripheral integration, deterministic reset behavior, and real-time responsiveness in voltage-variable environments.

Availability

DS80C323-QCD is available at Aetrix Electronics and suitable for industrial PLCs, smart metering systems, medical infusion pumps, and factory asset monitors requiring stable component supply across extended temperature and voltage ranges.

Supply support for DS80C323-QCD includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and high-reliability microcontrollers for demanding industrial, medical, and automotive applications.

The DS80C323-QCD belongs to Maxim's high-speed 8051-compatible microcontroller family, engineered to deliver 2.5× performance uplift in legacy 80C32-based systems while maintaining full software and pin compatibility - targeting upgrade paths in instrumentation and control.

FAQ

What is the operating voltage range of the DS80C323-QCD?

The DS80C323-QCD operates from 2.7V to 5.5V, enabling direct use in both 3.3V and 5V systems without level translation. This wide range supports battery-backed operation and simplifies power design in mixed-voltage industrial equipment. The DS80C323-QCD maintains full functionality-including dual UARTs, timers, and interrupt sources-across the entire voltage range, with specifications guaranteed down to 2.7V.

Is the DS80C323-QCD pin-compatible with standard 80C32 microcontrollers?

Yes, the DS80C323-QCD is fully pin-compatible with the 80C32 in its 44-pin PLCC package (QCD variant), including identical pin assignments for P0–P3, RST, XTAL1/XTAL2, EA, PSEN, ALE, WR, and RD. All standard 80C32 peripherals-three timers, two external interrupts, and one UART-map directly. The DS80C323-QCD adds new functions (second UART, INT2–INT5, power-fail signals) on previously unused or reserved pins, preserving backward hardware compatibility.

How does the dual data pointer improve firmware efficiency in DS80C323-QCD applications?

The DS80C323-QCD's dual data pointer (DPTR0 at 82h/83h, DPTR1 at 84h/85h) reduces memory block copy overhead by eliminating register save/restore operations. In a 64-byte move, DS80C323-QCD executes 1097 machine cycles versus 1869 with single DPTR - a 41% reduction. This acceleration is achieved by toggling DPS bit (86h) to switch active pointers mid-loop, enabling direct source/destination addressing without intermediate storage - critical for real-time data buffering in DS80C323-QCD-based controllers.

Can the DS80C323-QCD interface with slow peripherals like LCD modules or legacy RAM?

Yes, the DS80C323-QCD supports variable-speed MOVX access via the CKCON register (bit 2–0), allowing stretch values 0–7 that extend RD/WR strobe width from 2 to 9 machine cycles. At 18MHz, this yields strobe widths from 44ns to 200ns - sufficient for common 120ns–200ns static RAM and character LCDs. The DS80C323-QCD defaults to stretch=1 (3-cycle MOVX) on reset, ensuring compatibility with existing 80C32 designs without requiring hardware changes.

Does the DS80C323-QCD include built-in power-fail protection features?

Yes, the DS80C323-QCD integrates both power-fail reset and early-warning power-fail interrupt. The reset circuit asserts RST when VCC drops below ~2.5V (typ.), guaranteeing clean restart. Separately, the early-warning interrupt triggers ~100μs before reset activation, giving firmware time to save critical state to nonvolatile memory. These features eliminate need for external supervisors in DS80C323-QCD-based systems requiring graceful shutdown during brownouts.