Analog Devices Inc./Maxim Integrated DS80C320-QCL+T&R

Overview

DS80C320-QCL+T&R from Maxim Integrated is a high-speed, 80C32-compatible 8-bit microcontroller featuring a 4-clock-per-machine-cycle core, 33MHz maximum crystal frequency, 256 bytes of on-chip RAM, three 16-bit timer/counters, and dual full-duplex hardware serial ports. It operates from 4.25V to 5.5V and targets legacy 8051-based industrial control, instrumentation, and embedded communication systems requiring performance uplift without software rewrite.

For engineers reviewing the DS80C320-QCL+T&R datasheet, DS80C320-QCL+T&R pinout, DS80C320-QCL+T&R application, or DS80C320-QCL+T&R equivalent, key selection considerations include its 33MHz operation in 44-pin PLCC package, dual DPTR support for accelerated memory moves, programmable MOVX stretch timing, and pin compatibility with standard 80C32 designs-enabling drop-in replacement in existing 5V systems.

Technical Context

The DS80C320-QCL+T&R implements a redesigned 8051 core eliminating wasted clock cycles: all instructions execute in 4–28 oscillator cycles (vs. 12–48 in legacy 80C32), delivering up to 3× faster execution at same crystal frequency. Its dual data pointer (DPTR0/DPTR1) and configurable MOVX access timing (2–9 machine cycles via CKCON register) enable efficient interfacing with heterogeneous memory and peripherals.

It retains full 80C32 instruction set and SFR map compatibility while adding new peripherals-including power-fail reset, early-warning power-fail interrupt, and programmable watchdog timer-all accessible via dedicated SFRs without overlapping legacy addresses. Timer/counter operation defaults to 12-clock mode on reset for backward timing compatibility but supports 4-clock mode via CKCON bits.

Key Specifications

Pinout & Package

DS80C320-QCL+T&R is housed in a 44-pin Plastic Leaded Chip Carrier (PLCC) package with J-lead configuration, compatible with industry-standard PLCC sockets and reflow profiles. Pin 1 is marked by a notch on the top-left corner when viewed from above with notch oriented top-left.

Key Features

Applications

Equivalent & Alternatives

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

Compared with DS80C320-MCL+, DS80C320-QCL+T&R provides superior high-frequency stability and board-level EMI performance in compact layouts; compared with DS80C323-QCD+, it delivers 83% higher instruction throughput at 33MHz while maintaining identical firmware compatibility and peripheral feature set.

Availability

DS80C320-QCL+T&R is available at Aetrix Electronics and suitable for industrial automation, legacy equipment modernization, and embedded communications gateways requiring stable component supply across multi-year production cycles.

Supply support for DS80C320-QCL+T&R 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-QCL+T&R belongs to Maxim's high-speed 8051-compatible microcontroller family, designed specifically to extend the life of legacy 80C32-based systems with measurable performance gains while preserving software and hardware investment.

FAQ

Is DS80C320-QCL+T&R pin-compatible with standard 80C32 microcontrollers in PLCC packages?

Yes, DS80C320-QCL+T&R is fully pin-compatible with 80C32 devices in 44-pin PLCC packages. All signal names, pin positions, and electrical characteristics match the industry-standard 80C32 footprint, enabling direct replacement without PCB modification. The device retains identical I/O port structure, interrupt pin assignments, and memory bus signaling - verified in Maxim's official datasheet section "80C32 COMPATIBILITY".

What is the default MOVX access timing for DS80C320-QCL+T&R, and how is it configured?

The DS80C320-QCL+T&R defaults to a 3-machine-cycle MOVX access on power-up, corresponding to CKCON[2:0] = 001. This setting produces a 4-clock-wide RD/WR strobe at 25MHz (160ns), compatible with common 120ns–150ns SRAM. Timing is adjusted via bits CKCON.2–0 (SFR 8Eh), allowing stretch values from 0 (2 cycles) to 7 (9 cycles) - documented in Table 2 of the DS80C320 datasheet.

Does DS80C320-QCL+T&R include on-chip program memory, and how is code execution handled?

No, DS80C320-QCL+T&R contains no on-chip ROM or flash memory. Code execution occurs exclusively from external program memory (ROM/EPROM) accessed via the multiplexed P0 address/data bus and P2 high-order address lines. The EA pin must be tied LOW to enable external program fetches - confirmed in the "PIN DESCRIPTION" section under EA functionality and "MEMORY ACCESS" subsection.

How does the dual data pointer (DPTR0/DPTR1) in DS80C320-QCL+T&R improve memory block transfers?

The DS80C320-QCL+T&R's dual DPTR reduces 64-byte memory moves from 1869 to 1097 machine cycles - a 41% reduction - by eliminating software-managed address storage and reloading. DPTR0 (82h/83h) and DPTR1 (84h/85h) are selected via DPS bit (86h.0), enabling single-instruction pointer switching during block copy loops - validated in the "DUAL DATA POINTER" application example on page 13 of the datasheet.

What power-related safety features does DS80C320-QCL+T&R provide for industrial applications?

DS80C320-QCL+T&R integrates three critical power-monitoring features: (1) hardware power-fail reset triggered at ~4.0V, (2) early-warning power-fail interrupt activated at ~4.25V, and (3) programmable watchdog timer with independent timeout control. These allow deterministic state preservation and graceful shutdown during brownout conditions - detailed in the "PERIPHERAL OVERVIEW" and "POWER-FAIL RESET" sections of the datasheet.