NXP Semiconductors MC68HC908QT1MPE

Overview

MC68HC908QT1MPE from NXP (formerly Freescale) is an 8-bit HCS08-core microcontroller with 1 KB FLASH, 64 bytes RAM, and integrated 8-channel 8-bit ADC, designed for cost-sensitive embedded control in appliance motor drives, industrial sensors, and battery-powered instrumentation. It operates at up to 8 MHz bus speed using an internal RC oscillator, supports WAIT/STOP low-power modes, and features on-chip COP watchdog and LVI brownout protection.

For engineers reviewing the MC68HC908QT1MPE datasheet, MC68HC908QT1MPE pinout, MC68HC908QT1MPE application, or MC68HC908QT1MPE equivalent, key selection criteria include its 8-pin SOIC package, 1 KB programmable FLASH with block protection, internal oscillator trim capability, and support for keyboard interrupt and auto-wakeup functions in ultra-low-power monitoring scenarios.

Technical Context

The MC68HC908QT1MPE implements the M68HC08 CPU core with 16-bit address space, supporting indexed, extended, and relative addressing. Its oscillator module provides selectable clock sources: internal RC (±2% typical after trimming), external crystal, or external clock input via OSC1/OSC2 pins.

System integration includes a 16-bit Timer Interface Module (TIM) with input capture, output compare, and PWM generation; a Keyboard Interrupt Module (KBI) supporting up to 8-key matrix scan; and a Low-Voltage Inhibit (LVI) circuit with programmable trip point (2.5 V or 3.0 V) and hysteresis for reliable power failure detection.

Key Specifications

Pinout & Package

MC68HC908QT1MPE is housed in an 8-pin SOIC (Small Outline Integrated Circuit) package with 1.27 mm pitch, compliant with JEDEC MS-012AC. Pin assignments are validated per Figure 1-2 and Table 1-2 of Rev. 6 datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC68HC908QT2MPE and MC9RS08KA2CSC, the MC68HC908QT1MPE offers optimal cost/performance balance for minimal-footprint control tasks where 1 KB FLASH suffices and pin compatibility with legacy QT-series designs is critical.

Availability

MC68HC908QT1MPE is available at Aetrix Electronics and suitable for home appliance control, industrial sensor nodes, and smart power outlet designs requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for MC68HC908QT1MPE 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 delivering secure, scalable solutions for automotive, industrial, IoT, and mobile applications, with heritage from Freescale's HCS08 microcontroller portfolio.

The MC68HC908QT1MPE belongs to the HCS08-based QY/QT family - engineered for ultra-low-cost, low-pin-count embedded control in resource-constrained environments where minimal external components and robust power management are essential.

FAQ

What is the maximum operating frequency of the MC68HC908QT1MPE?

The MC68HC908QT1MPE supports a maximum bus clock frequency of 8 MHz when powered at 5.0 V. This is achieved using the internal RC oscillator (trimmed), an external crystal (up to 8 MHz), or an external clock source. At lower supply voltages (e.g., 3.0 V), the maximum rated bus speed is reduced to 4 MHz per electrical specifications in Section 16 of the datasheet. The MC68HC908QT1MPE does not support PLL-based frequency multiplication.

Does the MC68HC908QT1MPE support in-circuit programming?

Yes, the MC68HC908QT1MPE supports in-circuit programming via the MON (Monitor) module using a standard background debug interface (BDM) protocol. Programming requires a compatible BDM pod and Freescale Codewarrior development tools. The MC68HC908QT1MPE's FLASH memory supports page erase, mass erase, and byte/word programming - all executed under monitor mode control without requiring high-voltage VPP.

What are the voltage thresholds for the Low-Voltage Inhibit (LVI) feature on the MC68HC908QT1MPE?

The MC68HC908QT1MPE LVI module offers two programmable trip points: 2.5 V ±0.1 V and 3.0 V ±0.1 V, selected via the LVI control bits in the CONFIG1 register. Hysteresis is fixed at 0.2 V to prevent oscillation near threshold. When VDD drops below the selected trip point, the LVI asserts a hardware reset - ensuring deterministic behavior before supply collapse. This functionality is fully operational in both RUN and STOP modes.

Can the MC68HC908QT1MPE operate from a 3.3 V supply?

Yes, the MC68HC908QT1MPE is fully specified for operation from 2.7 V to 5.5 V, including 3.3 V nominal systems. At 3.3 V, the maximum bus clock is 4 MHz, and all I/O pins are 5 V-tolerant when configured as inputs - enabling direct interfacing with 5 V peripherals without level shifters. The internal oscillator remains functional, though accuracy degrades slightly versus 5 V operation (±5% typical untrimmed at 3.3 V).

How many I/O pins does the MC68HC908QT1MPE provide in its 8-pin SOIC package?

The MC68HC908QT1MPE provides five dedicated I/O pins in its 8-pin SOIC package: PTA0 through PTA3 and PTA4 (shared with OSC2/BUSCLKX4). VDD and VSS are power pins, and OSC1 is a dedicated oscillator input. All five port pins support digital input/output, with PTA1 and PTA2 additionally supporting keyboard interrupt functionality, and PTA3 serving as ADC input channel 0.