Analog Devices Inc./Maxim Integrated DS80C320-ENG

Overview

DS80C320-ENG from Maxim Integrated is a high-speed, 80C32-compatible 8-bit microcontroller designed for industrial embedded control upgrades. It delivers 25 MHz maximum crystal frequency, 4-clock-per-machine-cycle architecture (vs. legacy 12), dual hardware serial ports, 256 bytes on-chip RAM, and operates from –40°C to +85°C in 44-pin TQFP. It serves as a drop-in performance upgrade in legacy 5V 8051-based motor control, instrumentation, and industrial HMI systems.

For engineers reviewing the DS80C320-ENG datasheet, DS80C320-ENG pinout, DS80C320-ENG application, or DS80C320-ENG equivalent, this page provides verified electrical parameters, validated TQFP-44 pin mapping, confirmed dual-serial-port timing behavior, stretchable MOVX memory access configuration, and real-world substitution guidance for legacy 80C32 designs requiring higher throughput without PCB redesign.

Technical Context

The DS80C320-ENG implements a rearchitected 8051 core eliminating wasted clock cycles: all instructions execute in 4–28 oscillator cycles (vs. 12–48 in standard 80C32), with 159 opcodes achieving 3× speedup. Its dual data pointer (DPTR0/DPTR1) enables zero-overhead block memory moves via DPS bit toggling at SFR 86h.

Peripherals include two independent full-duplex UARTs (Serial Port 0 on P3.0/P3.1; Serial Port 1 on P1.2/P1.3), programmable watchdog timer, early-warning power-fail interrupt, and configurable MOVX strobe width (2–9 machine cycles via CKCON.2–0). Timer 0/1/2 default to 12-clock mode on reset for backward compatibility but support 4-clock operation when CKCON bits are set.

Key Specifications

Pinout & Package

DS80C320-ENG is supplied in a 44-pin Thin Quad Flat Package (TQFP) with 0.8 mm pitch, 10 mm × 10 mm body, and exposed thermal pad (non-electrical). Pin 1 is marked by dot; pins numbered counterclockwise.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DS80C320-ECL, DS80C320-ENG trades 8 MHz clock headroom for guaranteed –40°C startup and sustained operation in harsh environments; compared with AT89C51RD2-RLTUM, it delivers deterministic 4-cycle timing, dual UARTs, and MOVX configurability essential for real-time industrial I/O - making it the sole choice for legacy 80C32 upgrades demanding both speed and ruggedness.

Availability

DS80C320-ENG is available at Aetrix Electronics and suitable for industrial motor control, factory floor instrumentation, legacy system upgrades, and embedded HMI applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for DS80C320-ENG 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 automotive applications.

The DS80C320-ENG belongs to Maxim's high-speed 8051-compatible microcontroller family, engineered specifically to extend the life of legacy 5V 80C32 designs with measurable performance gains while preserving software and hardware investment.

FAQ

Is DS80C320-ENG pin-compatible with standard 80C32 devices in 44-pin TQFP packages?

Yes, DS80C320-ENG is fully pin-compatible with the industry-standard 80C32 in 44-pin TQFP packaging. All signal names, pin positions, and electrical characteristics align per Maxim's datasheet - enabling direct PCB-level replacement without layout changes. The DS80C320-ENG retains identical P0–P3 port mappings, reset, crystal, and EA pin locations, ensuring mechanical and functional interchangeability in existing 80C32 designs.

What is the default MOVX memory access timing for DS80C320-ENG after power-on reset?

After power-on reset, DS80C320-ENG defaults to a 3-machine-cycle MOVX strobe width (CKCON.2–0 = 001b), resulting in a 160 ns strobe at 25 MHz. This setting ensures compatibility with common 120 ns and 150 ns SRAM parts without requiring external wait-state generation. To achieve maximum speed, software must explicitly write CKCON = 0x00 to select 2-cycle mode (80 ns strobe at 25 MHz).

Does DS80C320-ENG support both Timer 1 and Timer 2 for baud rate generation on Serial Port 1?

No, DS80C320-ENG supports Timer 1 only for baud rate generation on Serial Port 1 (SP1). Unlike Serial Port 0 (SP0), which can use Timer 1 or Timer 2, SP1's baud rate is exclusively derived from Timer 1 - as documented in the High-Speed Microcontroller User's Guide. Timer 2 remains available for SP0 or general-purpose counting, but cannot serve SP1 timing.

How does the power-fail interrupt function in DS80C320-ENG, and what voltage threshold triggers it?

The DS80C320-ENG features an internal power-fail comparator that asserts the power-fail interrupt when VCC drops below 4.25 V - matching its minimum operating specification. This early-warning signal occurs before the device reaches reset threshold (typically ~3.8 V), allowing firmware to execute critical save routines (e.g., EEPROM writes) within ~10–20 ms before brownout shutdown. The interrupt is edge-triggered and requires software acknowledgment.

Can DS80C320-ENG operate reliably at 33 MHz, or is that rating exclusive to other variants?

DS80C320-ENG is rated for a maximum crystal frequency of 25 MHz across its full –40°C to +85°C operating range. While higher-speed variants like DS80C320-ENL support 33 MHz, the DS80C320-ENG's 25 MHz limit is thermally and electrically validated for industrial temperature stability. Attempting 33 MHz operation risks timing violations, especially in worst-case corners, and voids guaranteed specifications.