NXP Semiconductors MC68HC908JL8CP

Overview

MC68HC908JL8CP from Freescale Semiconductor is an 8-bit HCS08-core microcontroller with 8 KB on-chip Flash, 512 B RAM, and integrated peripherals including SCI, TIM, ADC (8-channel, 10-bit), KBI, and COP watchdog. It operates at up to 8 MHz bus frequency, supports 5 V operation, and targets embedded control in cost-sensitive industrial and appliance applications.

For engineers reviewing the MC68HC908JL8CP datasheet, MC68HC908JL8CP pinout, MC68HC908JL8CP application, or MC68HC908JL8CP equivalent, key selection criteria include Flash endurance (10k erase/write cycles), on-chip monitor ROM for in-system programming, low-power stop/wait modes, and compatibility with legacy HC08 toolchains and debug interfaces.

Technical Context

The MC68HC908JL8CP implements the HCS08 CPU core with enhanced addressing modes and a 16-bit index register. Its System Integration Module (SIM) provides clock generation via internal RC or external crystal oscillator, configurable bus speed scaling, and reset management including POR, LVI, COP, and illegal opcode detection.

Peripheral integration includes a 16-bit Timer Interface Module (TIM) with input capture, output compare, and PWM capability; an 8-channel 10-bit Analog-to-Digital Converter with software-triggered conversion; and a full-duplex Serial Communications Interface (SCI) supporting asynchronous communication at baud rates up to 115.2 kbps with programmable oversampling.

Key Specifications

Pinout & Package

MC68HC908JL8CP is housed in a 28-pin Plastic Dual In-line Package (PDIP) with 0.600-inch body width and 0.100-inch lead pitch. Pin assignments are defined per Figure 1-4 and Table 1-5 of Rev. 3.1 datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC9RS08KA8CP and MC68HC908JK8CP, the MC68HC908JL8CP offers optimal balance of Flash capacity, KBI hardware acceleration, and proven industrial qualification - making it preferred for retrofit and appliance control where legacy ecosystem alignment matters.

Availability

MC68HC908JL8CP is available at Aetrix Electronics and suitable for industrial motor control, home appliance MCU replacement, and legacy equipment modernization requiring stable component supply and long-term lifecycle support.

Supply support for MC68HC908JL8CP 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) was a leading designer of embedded processors, analog, and connectivity solutions for automotive, industrial, and consumer markets.

The MC68HC908JL8CP belongs to the HCS08 microcontroller family, engineered for cost-effective, low-power 8-bit control in appliances, industrial panels, and legacy system upgrades where Flash programmability and HC08 toolchain compatibility are essential.

FAQ

What is the maximum bus frequency supported by the MC68HC908JL8CP?

The MC68HC908JL8CP supports a maximum bus frequency of 8 MHz. This value is derived from the internal oscillator or external crystal configuration and directly governs instruction execution speed, peripheral timing (e.g., SCI baud rate generation and ADC conversion intervals), and real-time response latency. The device maintains timing compliance across its full operating voltage and temperature range.

Does the MC68HC908JL8CP include hardware support for keyboard scanning?

Yes, the MC68HC908JL8CP integrates a Keyboard Interrupt Module (KBI) that monitors up to four inputs on Port A (PTA0–PTA3). This hardware feature automatically detects key presses and generates an interrupt without CPU polling, reducing firmware overhead and enabling low-power wake-on-key functionality - a key advantage in appliance control panels.

Can the MC68HC908JL8CP be programmed in-circuit without an external programmer?

Yes, the MC68HC908JL8CP contains a 512-byte Monitor ROM that supports in-system programming via its SCI interface. Using standard UART signals (TxD/RxD), engineers can download and verify new firmware directly through the MC68HC908JL8CP's built-in bootloader - eliminating the need for dedicated programming hardware during development or field updates.

What is the Flash endurance specification for the MC68HC908JL8CP?

The MC68HC908JL8CP specifies 10,000 erase/write cycles for its 8 KB on-chip Flash memory. This endurance rating applies to individual Flash blocks and is validated under standard operating conditions (5 V, 25 °C). Block protection registers allow selective locking of critical firmware sections to prevent accidental overwrite during field updates.

How does the Low-Voltage Inhibit (LVI) function protect the MC68HC908JL8CP?

The MC68HC908JL8CP's LVI circuit continuously monitors VDD and asserts a hardware reset when supply voltage drops below 4.0 V (typical). This prevents unreliable operation due to brown-out conditions - ensuring deterministic reset behavior, avoiding corrupted Flash writes, and maintaining safe I/O states during power instability. LVI threshold is factory-trimmed and does not require external components.