Analog Devices Inc./Maxim Integrated DS80C320-QCG+

Overview

DS80C320-QCG+ from Maxim Integrated is a high-speed, 80C32-compatible 8-bit microcontroller with 4-clock-per-machine-cycle architecture, 256 bytes of on-chip RAM, three 16-bit timer/counters, and dual full-duplex hardware serial ports. It operates at up to 25MHz (0°C to +70°C), supports external 64kB ROM/RAM addressing, and integrates power-fail reset, programmable watchdog timer, and early-warning power-fail interrupt for industrial control and embedded instrumentation.

For engineers reviewing the DS80C320-QCG+ datasheet, DS80C320-QCG+ pinout, DS80C320-QCG+ application, or DS80C320-QCG+ equivalent, key selection considerations include its 44-pin PLCC package, 25MHz max clock speed at commercial temperature range, dual DPTR support for accelerated memory moves, variable MOVX stretch timing (2–9 machine cycles), and pin compatibility with legacy 80C32 designs in PLCC format.

Technical Context

The DS80C320-QCG+ implements a redesigned 8051 core eliminating wasted clock and memory cycles, delivering 2.5× average instruction execution speed versus standard 80C32 at identical crystal frequency. Its architecture decouples instruction timing (4 clocks/machine cycle) from default timer operation (12 clocks/cycle on reset), preserving backward compatibility for baud rate and timing-critical firmware.

It features two independent UARTs-Serial Port 0 (P3.0/P3.1) and Serial Port 1 (P1.2/P1.3)-with separate SFRs (SCON0/SCON1, SBUF0/SBUF1), and supports flexible off-chip data memory access via programmable MOVX stretch (CKCON.2–0) and dual data pointers (DPTR0 at 82h/83h, DPTR1 at 84h/85h, DPS at 86h.0).

Key Specifications

Pinout & Package

DS80C320-QCG+ is housed in a 44-pin Plastic Leaded Chip Carrier (PLCC) package with J-lead configuration, pin-compatible with standard 80C32 PLCC variants and suitable for surface-mount reflow assembly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DS80C320-QCG+, DS80C320-MCG+ offers identical functionality in a through-hole package for ease of evaluation, while DS80C320-ECL+ provides higher speed and extended temperature range in a space-efficient TQFP - both retain full 80C32 software and pin compatibility but differ in mechanical implementation and environmental rating.

Availability

DS80C320-QCG+ is available at Aetrix Electronics and suitable for industrial control systems, legacy embedded upgrades, multi-protocol gateways, and test instrumentation requiring stable component supply, long-term manufacturability, and RoHS-compliant sourcing.

Supply support for DS80C320-QCG+ 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) is a semiconductor company specializing in precision analog, mixed-signal, and high-reliability microcontrollers for industrial, medical, and communications applications.

The DS80C320-QCG+ belongs to Maxim's high-speed 8051-compatible microcontroller product line, designed to deliver 2.5× performance uplift over legacy 80C32 while maintaining full software and pin compatibility for cost-sensitive industrial upgrades.

FAQ

Is DS80C320-QCG+ pin-compatible with standard 80C32 microcontrollers?

Yes, DS80C320-QCG+ is fully pin-compatible with the 80C32 in the 44-pin PLCC package. All I/O pins, control signals (RST, EA, PSEN, ALE), and oscillator connections match exactly. External memory interface timing differs due to the 4-clock architecture, but pin mapping and default reset behavior preserve drop-in usability for most existing 80C32 designs.

What is the maximum operating frequency of DS80C320-QCG+ and how does it affect instruction timing?

The DS80C320-QCG+ supports a maximum crystal frequency of 25MHz across the 0°C to +70°C commercial temperature range. At this speed, single-cycle instructions execute in 160ns (4 clocks), delivering an average 2.5× speed improvement over the 12-clock 80C32. Timer peripherals default to 12-clock mode on reset for backward compatibility but can be reconfigured to 4-clock mode via CKCON register bits.

Does DS80C320-QCG+ include on-chip program memory or require external ROM?

DS80C320-QCG+ contains no on-chip program memory and requires external ROM or Flash for code storage. The EA pin must be tied LOW to enable external program memory access. It supports up to 64kB of external program space using P0 (AD0–AD7) and P2 (A8–A15), with PSEN controlling ROM chip enable - consistent with standard 80C32 memory mapping.

How does the dual data pointer (DPTR0/DPTR1) in DS80C320-QCG+ improve memory transfer efficiency?

The DS80C320-QCG+ implements two independent 16-bit data pointers (DPTR0 at SFR 82h/83h, DPTR1 at 84h/85h) selected via DPS bit (86h.0). This eliminates software overhead of saving/restoring addresses during block moves: a 64-byte transfer requires 1097 machine cycles with dual DPTR versus 1869 with single DPTR at 25MHz - a 41% reduction in execution time.

Can DS80C320-QCG+ interface directly with slow peripherals like LCD controllers without external wait-state logic?

Yes, DS80C320-QCG+ supports variable-speed MOVX execution via the CKCON register (bits 2–0), allowing data memory access to be stretched from 2 to 9 machine cycles. This enables direct connection to slow peripherals such as character LCDs or legacy UARTs without glue logic - the stretch value is software-configurable and can be changed dynamically based on the target device's response time.