NXP Semiconductors MC908AP32CFAER

Overview

MC908AP32CFAER from NXP Semiconductors (formerly Freescale) is an 8-bit HCS08-core microcontroller with 32 KB on-chip Flash, 1 KB RAM, and integrated peripherals including SCI, SPI, I²C, ADC, PWM, and TIM modules. It operates at up to 8 MHz internal bus speed, supports 2.7–5.5 V supply, and features low-power stop/wait modes - used in industrial sensor nodes and motor control subsystems.

For engineers reviewing the MC908AP32CFAER datasheet, MC908AP32CFAER pinout, MC908AP32CFAER application, or MC908AP32CFAER equivalent, key selection criteria include Flash endurance (100k erase/write cycles), 8-channel 10-bit ADC conversion time (≤14 µs), and availability of ROM-resident bootloader for field firmware updates.

Technical Context

The MC908AP32CFAER implements the HCS08 CPU core with enhanced BDM debug interface, 16-bit index register, and 8-level hardware stack. Its Clock Generator Module (CGM) integrates a PLL with programmable multipliers (×1 to ×32) and selectable reference dividers, enabling precise bus clock derivation from internal RC or external crystal sources.

System integration includes a System Integration Module (SIM) managing reset sources (POR, LVI, COP), interrupt prioritization across 24 vectors, and low-voltage inhibit with configurable trip points (2.5 V or 2.8 V). The ADC module supports single-ended/differential inputs with software- or timer-triggered conversions and configurable sample-and-hold timing.

Key Specifications

Pinout & Package

MC908AP32CFAER is housed in a 44-pin QFP (Quad Flat Package) with 0.8 mm pitch and 10 mm × 10 mm body size. Pin functions are defined per Table 1-2 and Figure 1-4 of the MC68HC908AP Family Data Sheet, Rev. 4.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC908AP64CFAER, the MC908AP32CFAER trades Flash capacity for cost-sensitive volume production; versus S9KEAZ128AMLH, it offers proven HCS08 toolchain continuity and lower gate count but lacks modern peripherals like USB or CAN FD.

Availability

MC908AP32CFAER is available at Aetrix Electronics and suitable for industrial motor control, smart sensor node, and automotive body control applications requiring stable component supply and long-term lifecycle support.

Supply support for MC908AP32CFAER 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 company formed from the spin-off of Philips' semiconductor division, specializing in secure connectivity solutions for automotive, industrial, and IoT markets.

The MC908AP32CFAER belongs to the legacy HCS08 microcontroller family designed for cost-effective, low-power embedded control in resource-constrained environments where deterministic real-time response and field-upgradable firmware are critical.

FAQ

What is the maximum operating frequency of the MC908AP32CFAER?

The MC908AP32CFAER achieves a maximum bus clock frequency of 8 MHz, derived from its internal Phase-Locked Loop (PLL) circuit. This PLL accepts reference clocks from either the internal 125 kHz RC oscillator or an external crystal (1–8 MHz), then multiplies them to generate the final system clock. The 8 MHz bus speed enables deterministic instruction execution within tight real-time deadlines typical in motor control and sensor acquisition systems. The MC908AP32CFAER maintains this performance across its full 2.7–5.5 V supply range.

Does the MC908AP32CFAER support in-system programming without external hardware?

Yes, the MC908AP32CFAER includes 1 KB of ROM-resident Monitor (MON) firmware that enables in-system programming via its SCI1 interface. Using standard UART commands, users can erase, program, and verify Flash memory without requiring a JTAG or BDM debugger. This capability is essential for field firmware updates in deployed equipment. The MC908AP32CFAER's MON ROM also supports checksum verification and memory dump operations, all accessible through ASCII command sequences sent over SCI.

What low-power modes does the MC908AP32CFAER support, and what are their typical current draws?

The MC908AP32CFAER supports Wait and Stop low-power modes. In Wait mode, the CPU halts while peripherals (ADC, TIM, SCI) remain active; typical current draw is ~100 µA at 3.3 V. In Stop mode, all clocks are gated except the LVI and reset logic; typical current draw drops to <1 µA at 3.3 V. Both modes retain RAM contents and allow wake-up via IRQ, KBI, or SCI activity. These modes make the MC908AP32CFAER suitable for battery-powered applications where duty-cycled operation is required.

How many ADC channels does the MC908AP32CFAER have, and what is their resolution and speed?

The MC908AP32CFAER integrates an 8-channel, 10-bit successive-approximation ADC. Each channel supports single-ended or differential input configurations. Conversion time is ≤14 µs per sample under optimal clock conditions (ADC clock between 500 kHz and 1 MHz), enabling effective sampling rates exceeding 70 kHz. The ADC includes dedicated result registers, configurable sample-and-hold timing, and software or timer-triggered start capability - features directly leveraged by the MC908AP32CFAER in closed-loop control and sensor data acquisition tasks.

Is the MC908AP32CFAER pin-compatible with other members of the MC68HC908AP family?

Yes, the MC908AP32CFAER is pin-compatible with MC908AP64CFAER, MC908AP16CFAER, and MC908AP8CFAER in the 44-pin QFP package. All share identical pin assignments for power, reset, oscillator, I/O ports, and peripheral signals (SCI, SPI, I²C, ADC, PWM). This allows hardware design reuse across variants - for example, a single PCB layout can accommodate any AP-family member by changing only the Flash-programmed firmware and configuration bits. The MC908AP32CFAER's compatibility simplifies prototyping and product family scaling.