NXP Semiconductors MC908QB8MPE

Overview

MC908QB8MPE from Freescale Semiconductor is an 8-bit M68HC08 core microcontroller with 8 KB on-chip FLASH, 512 B RAM, 10-bit ADC, ESCI and SPI interfaces, and integrated oscillator - designed for cost-sensitive industrial control and appliance applications requiring low-power operation and in-system programmability.

For engineers reviewing the MC908QB8MPE datasheet, MC908QB8MPE pinout, MC908QB8MPE application, or MC908QB8MPE equivalent, this page delivers verified functional architecture, security byte handling at $FFF6–$FFFD, BUSCLKX4 timing behavior, AWU wake-up capability, and FLASH protection mechanisms essential for secure firmware deployment and embedded system integration.

Technical Context

The MC908QB8MPE implements the M68HC08 CPU core with 16-bit address space, supports internal RC oscillator (1–8 MHz) or external crystal/RC source, and uses SuperFlash® technology for 100K-cycle endurance and 10-year data retention. Its memory map includes dedicated vector table at $FFC0–$FFFF and user-configurable security bytes at $FFF6–$FFFD.

It integrates peripheral modules including Auto Wakeup (AWU) with programmable timeout, ESCI supporting LIN 1.3 master/slave modes, and a 10-bit ADC with 8 input channels and software-selectable conversion clock. Monitor mode entry requires matching all eight security bytes - and denies access if five or more are zero.

Key Specifications

Pinout & Package

MC908QB8MPE is housed in a 28-pin SOIC package (SO-28) with 24 I/O pins, 2 power pins (VDD/VSS), 2 oscillator pins (OSC1/OSC2), and dedicated reset (RES) and IRQ pins.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC908QY8CDTE and MC908QB4MPE, the MC908QB8MPE uniquely balances 8 KB FLASH capacity, ESCI-based LIN support, and full AWU functionality - making it the only option among the three capable of hosting both application firmware and LIN protocol stack in standalone automotive body electronics.

Availability

MC908QB8MPE is available at Aetrix Electronics and suitable for home appliance control, industrial sensor nodes, smart power outlets, and automotive body control modules requiring stable component supply and long-term manufacturing continuity.

Supply support for MC908QB8MPE 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) was a leading designer of embedded processors, analog, and connectivity solutions for automotive, industrial, and consumer markets.

The MC908QB8MPE belongs to the M68HC08 family - engineered for cost-effective, low-power 8-bit control in resource-constrained environments where Flash programmability, integrated peripherals, and security are essential.

FAQ

What is the function of memory locations $FFF6–$FFFD in the MC908QB8MPE?

Memory locations $FFF6–$FFFD in the MC908QB8MPE hold eight user-programmable security bytes used to authenticate monitor mode entry. The host must transmit matching bytes during monitor initialization; if five or more are zero, access is denied. These locations must be programmed - even if unused for vectors - to prevent security bypass.

Does the MC908QB8MPE support LIN communication, and how is it implemented?

Yes, the MC908QB8MPE supports LIN 1.3 communication via its Enhanced Serial Communications Interface (ESCI) module. It provides hardware-level sync-break detection, automatic checksum generation, and configurable baud rates up to 19.2 kbps - enabling reliable slave-node operation in automotive body networks without software timing overhead.

What clock sources does the MC908QB8MPE support, and how is the bus clock derived?

The MC908QB8MPE supports internal RC oscillator (trimmable to ±2%), external crystal (1–8 MHz), or external RC network. The bus clock (BUSCLK) is derived by dividing BUSCLKX4 by 4; BUSCLKX4 feeds COP, TIM, and FLASH timing circuits and runs at up to 32 MHz when the internal oscillator operates at 8 MHz.

How does the Auto Wakeup Module (AWU) operate in the MC908QB8MPE?

The AWU in the MC908QB8MPE uses the internal RC oscillator to generate wake-up interrupts after a programmable delay ranging from ~1 ms to 1.6 s. It operates in Stop and Wait modes, allowing the MCU to remain in ultra-low-power state until triggered - ideal for battery-powered sensor nodes needing periodic measurement.

What is the maximum ADC resolution and input channel count supported by the MC908QB8MPE?

The MC908QB8MPE integrates a 10-bit successive-approximation ADC with eight analog input channels (AD0–AD7). Conversion time is software-configurable via ADCLK register, and the module supports both single-ended and differential sampling - delivering 1024 discrete levels for precision sensor signal acquisition.