NXP Semiconductors MC68HC908GR16CFA

Overview

MC68HC908GR16CFA from Freescale Semiconductor is an 8-bit HCS08-core microcontroller with 16 KB on-chip Flash, 512 B RAM, integrated 8-channel 10-bit ADC, SPI, ESCI, and TIM modules. It operates at up to 8 MHz bus frequency, supports low-power Wait/Stop modes, and targets embedded control in industrial sensors and appliance motor interfaces.

For engineers reviewing the MC68HC908GR16CFA datasheet, MC68HC908GR16CFA pinout, MC68HC908GR16CFA application, or MC68HC908GR16CFA equivalent, key selection criteria include Flash endurance (10k erase/write cycles), ADC sampling rate (up to 50 kSPS), CGM PLL lock time (<10 ms), and ESCI asynchronous serial support with programmable baud rates.

Technical Context

The MC68HC908GR16CFA implements the CPU08 core with 16-bit index register, 8-bit accumulator, and condition code register supporting 72 instructions. Its Clock Generator Module integrates a crystal oscillator, PLL with programmable multiplier (×1–×32), and base clock selector for flexible system timing.

The enhanced Serial Communications Interface (ESCI) provides full-duplex asynchronous communication with selectable clock source (CGMXCLK or BUS CLOCK), programmable stop bits (1 or 2), and LIN-compatible framing. The 8-channel 10-bit ADC includes internal reference, configurable sample-and-hold, and interrupt-on-conversion capability.

Key Specifications

Pinout & Package

MC68HC908GR16CFA is housed in a 48-pin QFP (Quad Flat Package) with 0.5 mm pitch, compliant with JEDEC MS-026. Pin assignments are defined per Chapter 1.4 and Figure 1-4 of Rev. 5.0 datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC68HC908GR16CFA, MC9RS08KA8CFD offers lower gate count and power but sacrifices PLL-based clock synthesis and ESCI LIN support, while MC9S08QG8CDT trades KBI and PLL for broader peripheral compatibility and mature S08 ecosystem support.

Availability

MC68HC908GR16CFA is available at Aetrix Electronics and suitable for industrial sensor nodes, home appliance motor controllers, smart thermostats, and POS terminal keypad interfaces requiring stable component supply across long-lifecycle production programs.

Supply support for MC68HC908GR16CFA 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) pioneered mixed-signal microcontrollers for cost-sensitive embedded control, emphasizing robustness, low power, and toolchain maturity.

The MC68HC908GR16CFA belongs to the HCS08 family, designed specifically for appliance, industrial, and consumer control applications demanding integrated analog peripherals, Flash reprogrammability, and deterministic real-time response.

FAQ

What is the maximum operating frequency of the MC68HC908GR16CFA?

The MC68HC908GR16CFA achieves a maximum bus frequency of 8 MHz, derived from its integrated PLL operating on an external crystal (1–8 MHz range). This frequency governs instruction execution speed, ADC sampling rate, and peripheral timing-critical for closed-loop motor control and sensor polling intervals in real-time applications. The PLL multiplier (×1–×32) allows precise scaling from low-frequency crystals.

Does the MC68HC908GR16CFA support in-circuit programming?

Yes, the MC68HC908GR16CFA supports in-system programming via its on-chip SuperFlash® memory and background debug mode (BDM). Programming requires only VDD, GND, BKGD, and RESET pins-no external high-voltage supply. This enables field firmware updates and eliminates the need for socketed programming in production or service workflows involving the MC68HC908GR16CFA.

How many ADC channels does the MC68HC908GR16CFA provide, and what is their resolution?

The MC68HC908GR16CFA integrates an 8-channel, 10-bit successive-approximation ADC with ±1 LSB integral nonlinearity. Channels AD0–AD7 map directly to PTB0–PTB7, supporting simultaneous sampling control via software triggers. Conversion time is 16 bus cycles (2 µs at 8 MHz), enabling up to 50 kSPS throughput-sufficient for temperature, pressure, and current sensing in industrial control systems using the MC68HC908GR16CFA.

What low-power modes are available on the MC68HC908GR16CFA?

The MC68HC908GR16CFA offers two hardware-supported low-power states: Wait mode (CPU halted, peripherals and interrupts active) and Stop mode (all clocks gated, 1 µA typical current draw). Both modes retain RAM contents and allow wake-up via IRQ, KBI, or reset. These modes are essential for battery-powered sensor nodes and standby operation in appliances using the MC68HC908GR16CFA.

Is the MC68HC908GR16CFA pin-compatible with other HCS08 family members?

No, the MC68HC908GR16CFA is not pin-compatible with other HCS08 devices due to its unique 48-pin QFP package and specific peripheral mapping (e.g., ESCI on PTD0/PTD1, KBI on PTA0–PTA7). While functional overlap exists with parts like MC9S08QG8CDT, PCB layout must be designed specifically for the MC68HC908GR16CFA's pinout and electrical characteristics per its Rev. 5.0 datasheet.