NXP Semiconductors MC908JL8CFAER2

Overview

MC908JL8CFAER2 from NXP (formerly Freescale) is an 8-bit HCS08 microcontroller featuring 8 KB on-chip Flash memory, 512 B RAM, and a 20 MHz CPU bus clock. It integrates a 10-bit ADC with 8 input channels, SCI serial interface, TIM timer module with PWM capability, and operates from 2.7–5.5 V. It targets cost-sensitive embedded control in appliance motor drives and industrial sensor nodes.

For engineers reviewing the MC908JL8CFAER2 datasheet, MC908JL8CFAER2 pinout, MC908JL8CFAER2 application, or MC908JL8CFAER2 equivalent, key selection criteria include its 20-pin SOIC package, internal RC oscillator option, COP watchdog, low-voltage inhibit (LVI), and ROM-based monitor for in-system programming - all critical for resource-constrained, field-upgradable designs.

Technical Context

The MC908JL8CFAER2 implements the HCS08 CPU core with enhanced addressing modes and a 16-bit index register. Its System Integration Module (SIM) provides bus clock generation, reset management, and interrupt control with three priority levels and hardware vectoring.

It supports two low-power modes - Wait (CPU halted, peripherals active) and Stop (all clocks gated except LVI and IRQ wake sources) - with recovery time under 4 µs from Stop mode. The integrated 10-bit ADC uses successive approximation with configurable sample time and software/hardware trigger options.

Key Specifications

Pinout & Package

MC908JL8CFAER2 is housed in a 20-pin SOIC (Small Outline Integrated Circuit) package with 0.300-inch body width and standard 1.27 mm 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 MC908JL8CFAER2, MC908JK8CDTE offers lower cost but sacrifices KBI and half the Flash/RAM; S9KEAZ128AMLH delivers architectural modernization and headroom but requires full firmware rewrite and layout changes.

Availability

MC908JL8CFAER2 is available at Aetrix Electronics and suitable for smart appliance control, industrial sensor nodes, and motor drive feedback units requiring stable component supply across extended production lifecycles.

Supply support for MC908JL8CFAER2 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 MC908JL8CFAER2 belongs to the legacy HCS08 microcontroller family, designed for cost-optimized, low-power embedded control in appliances and industrial equipment where proven reliability and long-term supply stability are essential.

FAQ

What is the maximum operating frequency of the MC908JL8CFAER2?

The MC908JL8CFAER2 supports a maximum bus clock frequency of 20 MHz, derived from its internal oscillator or external crystal. This yields a 100 ns instruction cycle time for deterministic real-time execution. The CPU core runs at bus clock speed, and all peripherals-including TIM, SCI, and ADC-are synchronized to this clock domain. Frequency scaling is not supported; operation above 20 MHz violates AC timing specifications.

Does the MC908JL8CFAER2 include a hardware watchdog timer?

Yes, the MC908JL8CFAER2 includes a Computer Operating Properly (COP) watchdog timer with windowed timeout capability. It uses an independent RC oscillator and features configurable timeout periods (0.5 ms to 1.0 s) and optional windowed operation to detect both premature and delayed service. The COP is enabled by default after reset and must be serviced regularly in firmware to prevent system reset.

Can the MC908JL8CFAER2 be programmed in-circuit without a dedicated programmer?

Yes, the MC908JL8CFAER2 contains a ROM-based Monitor (MON) that enables in-system programming via its SCI interface. Using standard UART commands, users can erase, program, and verify Flash memory without external hardware programmers. This capability is documented in Chapter 7 of the Rev. 3.1 datasheet and requires only a 3.3 V or 5 V UART connection and proper reset sequencing to enter monitor mode.

What ADC resolution and input count does the MC908JL8CFAER2 support?

The MC908JL8CFAER2 integrates a 10-bit successive approximation ADC with eight single-ended analog input channels (AD0–AD7). It supports software or hardware (TIM overflow) triggering, configurable sample time (1–20 bus cycles), and reference selection between VDD and internal bandgap. Conversion time ranges from 12 to 32 µs depending on bus clock and configuration.

Is the MC908JL8CFAER2 pin-compatible with other members of the HCS08 JL/JK series?

No, the MC908JL8CFAER2 is not pin-compatible with MC908JK8 or MC908KL8 variants. While all share the 20-pin SOIC package, pin functions differ significantly - for example, PTA6 serves as KBI6 on MC908JL8CFAER2 but as T2CH1 on MC908KL8. Migration requires PCB layout revision and firmware adaptation due to divergent peripheral mappings and register layouts.