NXP Semiconductors MCHC908MR8MFAE

Overview

MCHC908MR8MFAE from NXP Semiconductors (formerly Freescale) is an 8-bit HCS08 microcontroller designed for motor control and embedded real-time applications. It integrates 8 KB of on-chip FLASH, 512 B RAM, a dedicated Pulse-Width Modulator for Motor Control (PWMMC) with six PWM outputs and fault protection, 10-bit ADC with 8 channels, and dual timer interfaces (TIMA/TIMB). It operates at up to 8 MHz bus frequency and supports automotive-grade temperature range (–40°C to +125°C) in a 44-pin QFP package.

For engineers reviewing the MCHC908MR8MFAE datasheet, MCHC908MR8MFAE pinout, MCHC908MR8MFAE application, or MCHC908MR8MFAE equivalent, this page delivers verified technical context, validated pin functions, motor-control-specific features, and real-world substitution guidance - all grounded in Freescale's MC68HC908MR8 Rev. 4.1 Technical Data.

Technical Context

The MCHC908MR8MFAE implements the HCS08 CPU core with enhanced addressing modes and a 16-bit index register. Its System Integration Module (SIM) manages clock generation via a PLL-based Clock Generator Module (CGM), supporting crystal or external clock inputs and configurable bus frequencies up to 8 MHz.

The device includes two independent timer subsystems (TIMA and TIMB) with input capture, output compare, and PWM capabilities, plus a dedicated PWMMC module featuring dead-time insertion, complementary PWM pair configuration, and hardware fault shutdown via PTC0/PTC1 fault pins - all critical for brushless DC (BLDC) and stepper motor drive systems.

Key Specifications

Pinout & Package

44-pin QFP (Quad Flat Package), 10 mm × 10 mm body, 0.8 mm lead pitch, exposed thermal pad (non-electrical). Pinout conforms to MC68HC908MR8 pin assignment per Section 1.5 of Rev. 4.1 datasheet.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar motor control microcontroller applications.

Compared with MCHC908MR8MFAE, MC9S08AW60CFGE offers greater memory and CAN but sacrifices hardware motor fault response, while S9KEAZ128AMLH delivers ARM-class compute and flexibility at the cost of legacy ecosystem compatibility and qualification for harsh environments.

Availability

MCHC908MR8MFAE is available at Aetrix Electronics and suitable for automotive seat actuators, HVAC blower systems, and smart appliance motor drives requiring stable component supply across extended product lifecycles.

Supply support for MCHC908MR8MFAE 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

NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT markets, with deep heritage in microcontrollers dating to Motorola and Freescale.

The MCHC908MR8MFAE belongs to the HCS08 family - engineered specifically for cost-sensitive, real-time motor control applications where deterministic timing, hardware fault safety, and minimal external components are essential.

FAQ

What is the maximum bus frequency supported by the MCHC908MR8MFAE?

The MCHC908MR8MFAE supports a maximum bus frequency of 8 MHz, achieved via its integrated Clock Generator Module (CGM) with PLL. This frequency is confirmed in Section 8.4.2 and Table 21-1 (Electrical Specifications) of the MC68HC908MR8 Rev. 4.1 datasheet. The 8 MHz bus clock enables precise 125 ns instruction timing for real-time motor commutation loops in the MCHC908MR8MFAE.

Does the MCHC908MR8MFAE include a hardware watchdog timer?

Yes, the MCHC908MR8MFAE includes a Computer Operating Properly (COP) watchdog timer with user-configurable timeout intervals ranging from 0.5 ms to 1.6 s. As described in Section 15, the COP resets the device if not serviced within the selected window - a critical feature for fail-safe motor control in the MCHC908MR8MFAE.

Can the MCHC908MR8MFAE perform analog-to-digital conversion while running in low-power mode?

No - the 10-bit ADC in the MCHC908MR8MFAE is disabled in Stop mode and requires active clocks to operate. However, it remains functional in Wait mode when the CGM is configured to maintain ADC clocking. This behavior is specified in Sections 4.3.3 and 18.4 of the MC68HC908MR8 Rev. 4.1 datasheet for the MCHC908MR8MFAE.

How many independent PWM channels does the MCHC908MR8MFAE provide?

The MCHC908MR8MFAE provides six independent PWM outputs (PWM1–PWM6) through its dedicated Pulse-Width Modulator for Motor Control (PWMMC) module. These can be configured either as six single-ended channels or three complementary pairs with programmable dead time - a key capability documented in Section 9 of the MC68HC908MR8 Rev. 4.1 datasheet for the MCHC908MR8MFAE.

Is the MCHC908MR8MFAE pin-compatible with other HCS08 devices like the MC68HC908MR16?

No - the MCHC908MR8MFAE is not pin-compatible with the MC68HC908MR16. While both belong to the MR-series HCS08 family and share the 44-pin QFP package, their pin assignments differ significantly, particularly for ADC inputs, PWM outputs, and fault pins. Pin mapping must be verified against each device's respective datasheet - e.g., Section 1.5 of MC68HC908MR8 Rev. 4.1 for the MCHC908MR8MFAE.