NXP Semiconductors MC908QY8VDWE

Overview

MC908QY8VDWE from Freescale Semiconductor is an 8-bit M68HC08 core microcontroller with 8 KB on-chip FLASH, 256 B RAM, and integrated ADC10, ESCI, SPI, TIM, AWU, COP, and LVI modules. It operates at up to 8 MHz bus frequency, supports monitor mode programming, and features user-configurable security bytes at $FFF6–$FFFD for flash protection in embedded control applications.

For engineers reviewing the MC908QY8VDWE datasheet, MC908QY8VDWE pinout, MC908QY8VDWE application, or MC908QY8VDWE equivalent, this page delivers verified technical context, pin-level design meaning, real-world use cases in low-power industrial sensing and appliance control, and two validated alternative parts with documented functional and packaging differences.

Technical Context

The MC908QY8VDWE implements the M68HC08 CPU core with 16-bit address space, supporting indexed, extended, and relative addressing modes. Its oscillator module provides internal RC clock (±2% accuracy after trimming), external crystal support (1–8 MHz), and automatic clock switching between internal/external sources during runtime.

FLASH memory includes mass erase, page erase, and byte-program capabilities with hardware-based protection via CONFIG register bits and security byte validation ($FFF6–$FFFD) that blocks monitor mode entry if ≥5 of the eight bytes are zero - a hardened security feature introduced in the May 2012 Addendum.

Key Specifications

Pinout & Package

MC908QY8VDWE is housed in a 28-pin SOIC (SO-28) package with 300-mil body width and 0.025" lead pitch. Pin assignments follow the MC68HC908QB8/QY8 family layout, with shared port functionality and priority-based multiplexing per Chapter 1.4–1.6 of the datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC908QY4VDWE, the MC908QY8VDWE provides double FLASH and RAM for larger control algorithms and buffered communications; versus MC908QY8CDWE, it offers surface-mount compatibility for automated production while retaining identical register-level behavior and firmware binary compatibility.

Availability

MC908QY8VDWE is available at Aetrix Electronics and suitable for industrial sensor nodes, home appliance control units, smart meter front-ends, and legacy equipment retrofits requiring stable component supply across multi-year production cycles.

Supply support for MC908QY8VDWE 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

Freescale Semiconductor (now part of NXP Semiconductors) designed high-reliability, cost-optimized microcontrollers for automotive, industrial, and consumer applications using robust silicon processes and long-lifecycle support models.

The MC908QY8VDWE belongs to the M68HC08 family - engineered for deterministic real-time control in resource-constrained environments where low power, small footprint, and field-programmable FLASH are essential.

FAQ

What is the maximum operating frequency of the MC908QY8VDWE?

The MC908QY8VDWE supports a maximum bus clock frequency of 8 MHz. This is achieved using either the internal trimmed RC oscillator (calibrated to ±2% over temperature) or an external crystal up to 8 MHz. The internal BUSCLKX4 signal drives critical timing blocks including the COP watchdog and FLASH programming circuitry, ensuring reliable operation across voltage and temperature ranges.

How does the security feature at $FFF6–$FFFD work in the MC908QY8VDWE?

The MC908QY8VDWE requires eight user-defined security bytes stored at memory locations $FFF6–$FFFD to enable monitor mode entry. If five or more of those bytes are zero, monitor mode access is denied - a hardened anti-brute-force mechanism added in the May 2012 Addendum. These locations must be programmed even if unused for vectors, as blank values compromise flash protection.

Can the MC908QY8VDWE operate from a 3.3 V supply?

Yes, the MC908QY8VDWE operates across a 2.7–5.5 V supply range, making it fully compatible with standard 3.3 V systems. Its I/O pins are 5 V tolerant when configured as inputs, eliminating level shifters for interfacing with legacy 5 V peripherals - a key advantage in mixed-voltage designs.

What peripherals are integrated into the MC908QY8VDWE?

The MC908QY8VDWE integrates an 8-channel 10-bit ADC (ADC10), enhanced serial interface (ESCI) with LIN support, SPI master/slave, 16-bit timer interface module (TIM), auto wakeup unit (AWU), computer operating properly (COP) watchdog, keyboard interrupt (KBI), and low-voltage inhibit (LVI). All are accessible via PORTA and PORTB pins with priority-based function mapping.

Is the MC908QY8VDWE pin-compatible with other members of the QY8 family?

Yes, the MC908QY8VDWE shares identical pinout and electrical characteristics with other SO-28 variants in the QY8 family, including MC908QY8CDWE (DIP-28) and MC908QY4VDWE (4 KB FLASH). Firmware and PCB layout are interchangeable across these parts, enabling scalable memory selection without hardware redesign.