MC908JL8MDWE - HC08 8-bit MCU 8KB Flash 28-SOIC | NXP
MPN: MC908JL8MDWE ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.92 | $4.92 |
| 10 | $4.45 | $44.50 |
| 100 | $3.78 | $378.00 |
| 500 | $3.2 | $1,600.00 |
| 1,000 | $2.85 | $2,850.00 |
MC908JL8MDWE Overview
What is a HC08 microcontroller? The HC08 is NXP's (formerly Motorola/Freescale) 8-bit CISC microcontroller architecture, positioned in the cost-sensitive end of the embedded MCU spectrum. HC08 parts are organized into a hierarchy of sub-families - the JL/JK series sits within HC08 as a low-cost, FLASH-based derivative with integrated analog, targeted at simple control loops, sensor signal conditioning, and consumer white-goods. The HC08 architecture succeeds the earlier HC05 architecture and is in turn succeeded by the HCS08 and S08 architectures, but remains in production for long-life industrial designs.
Key features include 256 bytes of RAM, 13-channel 8-bit A/D, an internal clock generator with bus frequencies up to 8 MHz, and a wide operating voltage range suitable for 3 V and 5 V systems. The 28-SOIC package supports surface-mount assembly and provides adequate thermal performance for the typical 5–25 mA operating current of HC08 parts. Compared with modern Cortex-M0+ devices, the HC08 trades compute throughput and DMA for BOM cost, robustness and a stable 20+ year supply lifecycle.
Typical applications include appliance control boards (washing machines, dishwashers, microwave ovens), HVAC blower and fan controls, simple sensor hubs, motor control for low-DC-current loads, and battery-powered instrument front-ends. Its FLASH memory enables field re-programming for firmware updates without UV erasure.
When designing with the MC908JL8MDWE, ensure the integrated SCI UART pins are dedicated if asynchronous communication is required, and place the required bypass capacitors on the VDD/VSS pair as close as possible to the package pins. Designers migrating to newer platforms should consider S08 and Kinetis families; the HC908JL8 retains the longest-qualified long-life cycle.
Drop-in alternatives for MC908JL8MDWE — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with MC908JL8MDWE (same form factor and footprint) — differing in Core, Operating Temperature, Package, RAM, Supply Voltage.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC9S08JL8CDWE
✅ Drop-In📋 Reference alternative (not in catalog)
MC9S08JS16CWJ
✅ Drop-In✓ In Stock
$3.85 / Unit
View Datasheet →MC908JL16MDWE
✅ Drop-In📋 Reference alternative (not in catalog)
MC908JK8MDWE
✅ Drop-In📋 Reference alternative (not in catalog)
MC908JL8MDWE Maximum Ratings & Electrical Characteristics
| Family | HC08 |
| Core | HC08 8-bit |
| Bus Frequency | 8 MHz |
| Program Memory | 8 KB (8K x 8) FLASH |
| RAM | 256 bytes |
| A/D Converter | 8-bit, 13 channels |
| Serial Interface | SCI (UART) |
| Package | 28-SOIC |
| Pin Count | 28 |
| Mounting Type | Surface Mount |
| Operating Temperature | -40 °C to +85 °C |
| Temperature Grade | Industrial (MD suffix) |
| Data Bus Width | 8 bit |
| Supply Voltage | 3 V to 5.5 V (typical HC08 range) |
| Lead-Free / RoHS | Lead-Free / RoHS Compliant |
MC908JL8MDWE Pin Configuration
| Pin 1 | PTA0 — Port A bit 0 / ADC channel |
| Pin 2 | PTA1 — Port A bit 1 / ADC channel |
| Pin 3 | PTA2 — Port A bit 2 / ADC channel |
| Pin 4 | PTA3 — Port A bit 3 / ADC channel |
| Pin 5 | PTA4 — Port A bit 4 / ADC channel |
| Pin 6 | PTA5 — Port A bit 5 / ADC channel |
| Pin 7 | PTA6 — Port A bit 6 / ADC channel |
| Pin 8 | PTA7 — Port A bit 7 / ADC channel |
| Pin 9 | PTB0 — Port B bit 0 |
| Pin 10 | PTB1 — Port B bit 1 |
| Pin 11 | PTB2 — Port B bit 2 |
| Pin 12 | PTB3 — Port B bit 3 |
| Pin 13 | PTB4 — Port B bit 4 |
| Pin 14 | PTB5 — Port B bit 5 |
| Pin 15 | PTB6 — Port B bit 6 |
| Pin 16 | PTB7 — Port B bit 7 |
| Pin 17 | VDD — Positive supply |
| Pin 18 | VSS — Ground |
| Pin 19 | OSC1 — Oscillator input |
| Pin 20 | OSC2 — Oscillator output |
| Pin 21 | RST — Reset input |
| Pin 22 | IRQ — External interrupt |
| Pin 23 | TXD — SCI transmit (UART) |
| Pin 24 | RXD — SCI receive (UART) |
| Pin 25 | BKGD — Background Debug Mode |
| Pin 26 | ADC0 — ADC reference / channel |
| Pin 27 | ADC1 — ADC channel |
| Pin 28 | ADC2 — ADC channel |
Typical Applications
MC908JL8MDWE is suitable for 6 applications: White-Goods Appliance Control, HVAC Blower and Fan Controller, Sensor Hub / Analog Front End, Battery-Powered Instrument Front End, Low-Current Motor Control, Industrial Sensor Transmitter.
White-Goods Appliance Control
The MC908JL8MDWE's HC08 core at 8 MHz, 8 KB FLASH and 13-channel 8-bit ADC make it well-suited for appliance control boards in washing machines, dishwashers and microwave ovens. The integrated SCI supports UART comms for keypad/display modules, while the 13 ADC inputs read multiple temperature, level and motor-current sensors concurrently. The HC08 FLASH permits in-circuit firmware updates for production line revision control. Compared with newer ARM Cortex-M0 parts, this MCU keeps BOM cost low and leverages two decades of stable HC08 firmware IP. Drop the part onto a 28-SOIC footprint with 3.3 V or 5 V supply and you have a proven control platform with NXP long-life supply. Source: NXP HC08JL8 datasheet.
Recommended
HVAC Blower and Fan Controller
For HVAC blower controllers, the MC908JL8MDWE provides 8-bit ADC for reading temperature and air-flow sensors, GPIO-driven TRIAC or relay control of fan motors, and SCI for inter-board communication with a master thermostat. The industrial -40 °C to +85 °C temperature range covers unconditioned air-handler spaces. The HC08's deterministic interrupt latency simplifies zero-cross TRIAC timing. Designers pair the MCU with MOC3021 opto-isolators and 24 VAC zero-cross detection, yielding a low-cost reliable controller. The 28-SOIC package supports a single-sided PCB to meet aggressive HVAC BOM cost targets. Source: NXP HC08JL8 datasheet.
Recommended
Sensor Hub / Analog Front End
As a low-cost sensor hub, the MC908JL8MDWE aggregates up to 13 analog sensor channels via its 8-bit ADC, applies simple digital filtering in software, and forwards results over the SCI UART to a higher-level host processor. The 8 KB FLASH holds a sensor-library with calibration tables, and 256 B RAM supports per-channel moving averages. This pattern is common in industrial instrumentation and white-goods where a dedicated sensor board is preferable to a more expensive SoC. The MCU's industrial temperature grade supports unconditioned cabinet mounting. Drop-in compatible successors like the S9S08JL8 extend supply life.
Recommended
Battery-Powered Instrument Front End
Battery-powered instruments such as portable gas detectors or digital calipers benefit from the HC08's low cost and the MC908JL8MDWE's straightforward sleep/idle current behavior at 3 V supply. The MCU wakes on a sensor interrupt, scans selected ADC channels, packages data over SCI, and returns to sleep. The 8-bit core at 8 MHz is sufficient for filter and protocol stack execution. Industrial-grade parts survive tool-shop environments. The 28-SOIC supports hand-soldered prototypes and standard reflow production. Where more precision is required, pair with a separate 12-bit ADC such as the MAX147AEPA in a small analog front end. Source: NXP HC08JL8 datasheet.
Recommended
Low-Current Motor Control
For small DC or stepper motor control boards (e.g., lens focus, valve actuators, dispenser pumps), the MC908JL8MDWE provides the timing and ADC resources needed for brushed DC PWM commutation or simple step-pulse generation. The 8 MHz bus rate supports up to a few kHz PWM at reasonable resolution. The 13 ADC inputs read current shunt, position sensors and supply voltage. Industrial temperature grade supports under-hood automotive aftermarket or unconditioned factory cabinet mounting. The 28-SOIC footprint is widely understood by contract assemblers, minimizing manufacturing risk. Source: NXP HC08JL8 datasheet.
Recommended
Industrial Sensor Transmitter
Industrial 4-20 mA loop-powered transmitters often use HC08-class 8-bit MCUs as their control brain. The MC908JL8MDWE reads a sensor via the 8-bit ADC, applies linearization in firmware, and modulates the loop current through a PWM-driven transistor and shunt. The 28-SOIC package and industrial temperature grade suit field-mounted enclosures. The HC08's deterministic interrupt response simplifies IEC 61508-style firmware practice where applicable. When higher ADC resolution is required, replace the on-chip ADC with a 12- or 16-bit external part such as the MAX1300CQH+D. Source: NXP HC08JL8 datasheet.
Recommended
Recommended Products Summary
Engineering reference data for MC908JL8MDWE — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC9S08JL8CDWE | MC9S08JS16CWJ | MC908JL16MDWE | MC908JK8MDWE |
|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 28-SOIC | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same | 28-SOIC - same |
| Core | HC08 8-bit 8 MHz | S08 8-bit 20 MHz | S08 8-bit 20 MHz | HC08 8-bit 8 MHz | HC08 8-bit 8 MHz |
| Flash Memory | 8 KB | 8 KB | 16 KB | 16 KB | 8 KB |
| RAM | 256 B | 256 B | 512 B | 256 B | 256 B |
| ADC | 8-bit, 13 ch | 12-bit, 8 ch | 12-bit, 8 ch | 8-bit, 13 ch | 8-bit, 8 ch |
| Serial Interface | SCI | SCI + SPI + I2C | SCI + SPI + I2C + USB | SCI | SCI |
| Operating Temperature | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C | -40 °C to +85 °C |
Key Differentiators
- S08 HCS08 successor in same 28-SOIC footprint (vs MC9S08JL8CDWE)
- Larger FLASH on same 28-SOIC footprint (vs MC908JL16MDWE)
- Smaller family variant with reduced ADC count (vs MC908JK8MDWE)
Design Notes
Place a 100 nF decoupling capacitor as close as possible to the VDD (pin 17) and VSS (pin 18) pair of the MC908JL8MDWE. Add a bulk 10 uF electrolytic or tantalum capacitor near the supply pin for transient-load support. Route the analog supply (if separate) through a ferrite bead from digital VDD to minimize ADC noise. Keep the OSC1/OSC2 traces short and isolated from noisy switching lines to reduce clock jitter. Estimated: standard MCU reference design per NXP HC08 application notes.
Do not omit the external reset components on the RST pin - the HC08 requires a defined rise time at power-up to enter a clean start state. Leave the BKGD pin accessible for BDM programming during development, even if not used in production. Verify the ADC reference voltage is well-bypassed; an unstable VREF directly causes ADC noise. Ensure unused ADC channels are tied to a defined voltage (GND) to prevent floating-input leakage. Source: NXP HC08JL8 datasheet.
When using the SCI UART at high baud rates above 57.6 kbps, keep TXD/RXD traces short and away from switching power or motor traces. Place a series resistor close to the TXD pin if the trace exceeds 50 mm, to damp reflections. For 5 V tolerant connection to a 3.3 V host, use a discrete level shifter or a series resistor divider on RXD. The HC08 SCI does not include hardware flow control on the JL8 die, so software XON/XOFF or character framing is required for robust comms. Source: NXP HC08JL8 datasheet.
Compliance Information
Lead-Free / RoHS compliant per NXP product page. Not AEC-Q100 qualified (industrial grade only).
