NXP Semiconductors MCR908JK1ECDWE

Overview

MCR908JK1ECDWE from NXP Semiconductors (formerly Freescale) is an 8-bit HCS08 microcontroller with 1 KB on-chip FLASH, 64 bytes RAM, and integrated 8-channel 8-bit ADC. It features a 20-pin SOIC package, internal RC oscillator (4 MHz), and supports low-power Wait/Stop modes for battery-operated sensor interfaces and industrial control panels.

For engineers reviewing the MCR908JK1ECDWE datasheet, MCR908JK1ECDWE pinout, MCR908JK1ECDWE application, or MCR908JK1ECDWE equivalent, key selection criteria include its 1 KB FLASH size, 8-bit ADC resolution, SOIC-20 footprint, COP watchdog, and KBI keyboard interrupt support for human-interface designs.

Technical Context

The MCR908JK1ECDWE implements the HCS08 CPU core with 16-bit address bus, supporting up to 64 KB memory space. Its System Integration Module (SIM) provides clock generation, reset control, and interrupt management, while the Timer Interface Module (TIM) delivers input capture, output compare, and PWM generation with two independent channels.

It integrates a 8-channel 8-bit successive-approximation ADC with programmable conversion time (16–256 µs), configurable reference (VDD or external), and interrupt-on-complete capability. The Keyboard Interrupt Module (KBI) supports debounced scanning of up to 8 keys via Port A pins.

Key Specifications

Pinout & Package

Package: 20-pin Small Outline Integrated Circuit (SOIC), 0.300-inch body width, RoHS-compliant, surface-mount compatible.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC908JK1ECDWE and MC908JK3ECDWE, the MCR908JK1ECDWE offers optimal cost/performance balance for fixed-function UI and sensor tasks where 1 KB FLASH and basic peripherals suffice-avoiding overdesign while ensuring long-term availability through NXP's extended product support.

Availability

MCR908JK1ECDWE is available at Aetrix Electronics and suitable for industrial control panels, smart appliance interfaces, and portable sensor nodes requiring stable component supply across multi-year production cycles.

Supply support for MCR908JK1ECDWE 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 specializing in secure connectivity solutions for automotive, industrial, and IoT applications.

The MCR908JK1ECDWE belongs to the legacy HCS08 microcontroller family, designed for cost-sensitive, low-power embedded control applications requiring high reliability and long-term manufacturability.

FAQ

What is the maximum operating frequency of the MCR908JK1ECDWE?

The MCR908JK1ECDWE operates with an internal RC oscillator calibrated to 4 MHz (±2%) at 5 V and 25 °C. When using an external crystal, the maximum system bus frequency is 8 MHz. This frequency determines instruction execution speed and ADC conversion timing-critical for real-time response in UI and sensor applications. The MCR908JK1ECDWE does not support PLL multiplication or higher-frequency external clocks.

Does the MCR908JK1ECDWE support in-system programming (ISP)?

Yes, the MCR908JK1ECDWE supports in-system programming via its built-in Monitor ROM (MON). Using a standard UART interface and the MON command set, firmware can be erased, programmed, and verified without removing the device from the PCB. This capability is fully implemented in the MCR908JK1ECDWE and requires only a 3.3 V or 5 V UART level shifter and proper BKGD pin handling during entry.

What are the ADC input voltage range and reference options for the MCR908JK1ECDWE?

The MCR908JK1ECDWE ADC accepts analog inputs from 0 V to VDD (single-ended) or 0 V to VREFH (differential), with VREFH selectable as either VDD or an external voltage applied to the ADCVREFH pin. Input channels are multiplexed across PTA1–PTA5 and PTD0–PTD2. The MCR908JK1ECDWE ADC achieves ±2 LSB integral nonlinearity and supports conversion times from 16 µs (fastest) to 256 µs (highest accuracy).

How does the Keyboard Interrupt Module (KBI) function on the MCR908JK1ECDWE?

The KBI in the MCR908JK1ECDWE monitors up to eight input lines (mapped to PTA1–PTA5 and PTD0–PTD2) for key press/release events with built-in 12.8 ms debounce filtering. It generates an interrupt when a state change occurs, and the KBI status register identifies which line triggered the event. This hardware acceleration eliminates polling overhead in the MCR908JK1ECDWE firmware, reducing CPU load and power consumption in UI applications.

Is the MCR908JK1ECDWE pin-compatible with the original Freescale MC68HC908JK1?

Yes, the MCR908JK1ECDWE is pin-compatible and functionally equivalent to the Freescale MC68HC908JK1 in the 20-pin SOIC package. Both share identical pin assignments, electrical characteristics, memory map, and instruction set. The MCR908JK1ECDWE maintains full backward compatibility-enabling drop-in replacement in legacy designs without PCB or firmware changes.