MC68HC908JL3ECDW - 8-bit HC08 MCU, 4KB Flash, 8MHz | NXP
MPN: MC68HC908JL3ECDW ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $8.5 | $8.50 |
| 10 | $7.65 | $76.50 |
| 100 | $6.4 | $640.00 |
| 500 | $5.5 | $2,750.00 |
| 1,000 | $4.85 | $4,850.00 |
MC68HC908JL3ECDW Overview
An 8-bit microcontroller (MCU) is a single-chip computer that combines a CPU, RAM, ROM/FLASH, and peripheral interfaces on one die. The 8-bit HC08 architecture from NXP (formerly Freescale and Motorola) is a classic CISC core widely used in cost-sensitive applications such as appliance control, automotive body electronics, industrial timers, and simple sensor interfaces. MCUs in the wider hierarchy sit under microcontrollers, then embedded processors, then integrated circuits. The M68HC08 family is based on the Customer-Specified Integrated Circuit (CSIC) design strategy, which allows multiple flash/RAM/package variants from the same silicon platform.
Key features of the MC68HC908JL3ECDW include 4 KB FLASH (4K x 8), an 8 MHz maximum internal bus frequency, an integrated timer module, and a 28-SOIC wide-body package suitable for hand-soldered prototypes and through-hole-style PCB layouts converted to surface mount. The HC08 instruction set is binary-compatible across the family, enabling code reuse between JL3, JK3 and JK1 variants.
The part uses a Harvard-style internal architecture with unified addressing for code and data in the CPU08 core. The 8 MHz internal bus speed delivers roughly 1 MIPS of effective throughput at the standard HC08 instruction cycle ratio. On-chip peripherals and FLASH simplify board design by removing external program memory and reducing BOM cost.
Typical applications include low-end white-goods controllers (washing machines, microwaves), HVAC thermostats and timers, simple remote controls, automotive accessory modules, and industrial sensor signal conditioners. The wide SOIC footprint eases lab rework and is friendly to low-density two-layer boards.
Designers should be aware that the M68HC08JL3E family has been declared "Not Recommended for New Design" (NRND) on NXP's product page and that any new project should evaluate S08, S12 or ARM Cortex-M alternatives. Existing boards, however, can continue to be serviced by NXP and authorized distributors, and the SWD/background-debug-mode (BDM) toolchain remains supported.
This page consolidates distributor pricing, same-family drop-in alternatives, and practical design notes not found in the original manufacturer datasheet, giving engineers a one-stop reference for sourcing and reusing this legacy 8-bit MCU.
Drop-in alternatives for MC68HC908JL3ECDW — 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 MC68HC908JL3ECDW (same form factor and footprint) — differing in Architecture, Package, Program Memory Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC908JL3ECDWE
✅ Drop-In✓ In Stock
$6.0657 / Unit
View Datasheet →MC68HC908JL3CFAE
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MC68HC908JK3ECDW
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MC68HLC908JL3ECDW
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MC68HRC908JL3ECDW
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MC68HC908JL3ECDW Maximum Ratings & Electrical Characteristics
| Product Family | M68HC08 |
| Core | CPU08 (8-bit HC08) |
| Program Memory Type | FLASH |
| Program Memory Size | 4 KB (4K x 8) |
| Maximum CPU Frequency | 8 MHz |
| Data Bus Width | 8-bit |
| Package / Case | 28-SOIC (DW, wide-body) |
| Mounting Type | Surface Mount |
| Pin Count | 28 |
MC68HC908JL3ECDW Pin Configuration
| Pin 1 | IRQ — External interrupt request input |
| Pin 2 | VSS — Ground reference |
| Pin 3 | OSC1 — Crystal/oscillator input or RC connection |
| Pin 4 | OSC2 — Crystal/oscillator output |
| Pin 5 | VDD — Positive supply voltage |
| Pin 6 | RST — Reset input (active low) |
| Pin 7 | PTB0 — General-purpose I/O port B bit 0 |
| Pin 8 | PTB1 — General-purpose I/O port B bit 1 |
| Pin 9 | PTB2 — General-purpose I/O port B bit 2 |
| Pin 10 | PTB3 — General-purpose I/O port B bit 3 |
| Pin 11 | PTB4 — General-purpose I/O port B bit 4 |
| Pin 12 | PTB5 — General-purpose I/O port B bit 5 |
| Pin 13 | PTB6 — General-purpose I/O port B bit 6 |
| Pin 14 | PTB7 — General-purpose I/O port B bit 7 |
| Pin 15 | PTA0 — General-purpose I/O port A bit 0 |
| Pin 16 | PTA1 — General-purpose I/O port A bit 1 |
| Pin 17 | PTA2 — General-purpose I/O port A bit 2 |
| Pin 18 | PTA3 — General-purpose I/O port A bit 3 |
| Pin 19 | PTA4 — General-purpose I/O port A bit 4 |
| Pin 20 | PTA5 — General-purpose I/O port A bit 5 |
| Pin 21 | PTA6 — General-purpose I/O port A bit 6 |
| Pin 22 | PTA7 — General-purpose I/O port A bit 7 |
| Pin 23 | VDD — Positive supply voltage (secondary) |
| Pin 24 | VSS — Ground reference (secondary) |
| Pin 25 | BKGD — Background Debug Mode (BDM) data |
| Pin 26 | TCLK — Timer external clock input |
| Pin 27 | TXD — SCI transmit output (per device mask) |
| Pin 28 | RXD — SCI receive input (per device mask) |
Typical Applications
MC68HC908JL3ECDW is suitable for 7 applications: White-Goods Appliance Control, HVAC Thermostat and Timer Module, Simple IR Remote Control, Industrial Sensor Signal Conditioner, Automotive Body and Accessory Module (legacy), Battery Charger and Power Management UI, Educational and Hobbyist Embedded Projects.
White-Goods Appliance Control
The MC68HC908JL3ECDW fits white-goods control boards (washing machines, dishwashers, microwave ovens) where its 4 KB FLASH stores the appliance control state machine, motor timing and user-interface logic. The 28-SOIC package is hand-solder friendly for low-volume SKUs, while 8 MHz CPU performance is more than sufficient for keypad debouncing, relay sequencing and LED indicators. Designers benefit from the HC08's deterministic interrupt latency and BDM-based in-system reprogramming during factory firmware provisioning. Compared with switching to a Cortex-M0, the JL3 remains attractive when the firmware is already ported and the BOM cost is dominated by other components.
Recommended
HVAC Thermostat and Timer Module
Use the MC68HC908JL3ECDW as the timing brain of an HVAC thermostat, simple programmable timer, or fan-speed controller. The 4 KB FLASH holds the schedule tables and PI/PID setpoint loops, while the 8 MHz CPU08 delivers a comfortable margin for slow control loops (sub-100 Hz). Wide industrial temperature grade supports installation in equipment closets and outdoor enclosures. Compared with discrete 555-timer circuits, the JL3 replaces multiple analog parts, adds EEPROM-style user setting storage, and simplifies UL/CE compliance through integrated supervisory functions.
Recommended
Simple IR Remote Control
Cost-sensitive IR remote controls for TVs, set-top boxes, fans and consumer audio gear are a natural fit for the MC68HC908JL3ECDW. The 4 KB FLASH stores the IR protocol library (RC5, NEC, Sony), device key map and battery-saving routines, while the 8 MHz CPU handles pulse generation and debouncing. The 28-SOIC package fits the spacious PCBs typical of remote designs, and the HC08's low-power wait modes stretch alkaline battery life beyond one year. For higher protocol counts, designers can drop in the 8 KB JL8 family member on the same 28-SOIC footprint if the software can fit.
Recommended
Industrial Sensor Signal Conditioner
Pair the MC68HC908JL3ECDW with analog front ends to create 4-20 mA loop-powered sensor conditioners for pressure, temperature or level transmitters. The MCU performs linearization, range scaling and HART-lite modulation, while its 8 MHz throughput exceeds the needs of 50 ms loop update times. The wide industrial temperature rating supports outdoor installations, and the HC08 BDM port enables field firmware updates through a handheld programmer. Compared with op-amp-only designs, the JL3 enables digital trim and self-calibration that improve overall transmitter accuracy.
Recommended
Automotive Body and Accessory Module (legacy)
The MC68HC908JL3ECDW has historically been deployed in non-safety automotive body electronics such as mirror adjusters, seat controllers, basic lighting timers and rear-window defroster logic, where its industrial temp range and 4 KB FLASH are sufficient. Designers must confirm AEC-Q100 is not required for the target module, since the JL3 is industrial-grade. For new automotive designs with safety implications, NXP recommends the S12 or Kinetis E family with proper AEC-Q100 qualification. The JL3 remains valuable for aftermarket automotive accessories and hobby-grade retrofits.
Recommended
Battery Charger and Power Management UI
Implement the user interface and charge-state logic of a sealed lead-acid, NiCd or Li-ion charger with the MC68HC908JL3ECDW. The MCU monitors voltage/current dividers, drives LED status indicators, and implements charge termination algorithms within its 4 KB FLASH. At only a few hundred instructions, the typical CC/CV charger state machine is comfortable, and the HC08's BDM allows engineering to adjust charge parameters without recompiling. The 28-SOIC footprint supports both factory automation (reflow) and field-replacement (hand-solder) environments.
Recommended
Educational and Hobbyist Embedded Projects
Universities, makers and self-learners use the MC68HC908JL3ECDW as a teaching vehicle for CISC assembly, interrupt programming and BDM debugging. The 4 KB FLASH is small enough to manage in hand-written assembly yet large enough to host a meaningful bootloader, while 8 MHz exercises fundamental timing concepts. Industry-standard SOIC-28 is breadboard-friendly via carrier boards, and legacy P&E Multilink or MON08 debuggers remain available on the surplus market. The HC08's mature toolchain and abundant reference code lower the entry barrier for first-time embedded engineers.
Recommended
Recommended Products Summary
Engineering reference data for MC68HC908JL3ECDW — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC908JL3ECDWE | MC68HC908JL3CFAE | MC68HC908JK3ECDW | MC68HLC908JL3ECDW | MC68HRC908JL3ECDW |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 28-SOIC (DW) | 28-SOIC (DW) | 28-SOIC (DW) | 28-SOIC (DW) | 28-SOIC (DW) | 28-SOIC (DW) |
| Core / Family | HC08 / CPU08 | HC08 / CPU08 | HC08 / CPU08 | HC08 / CPU08 (JK variant) | HC08 / CPU08 (HLC low-V mask) | HC08 / CPU08 (HRC RC osc) |
| Program Memory | 4 KB FLASH | 4 KB FLASH | 4 KB FLASH | 4 KB FLASH | 4 KB FLASH | 4 KB FLASH |
| Maximum CPU Frequency | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz (low-Vdd variant) | 8 MHz (internal RC) |
| Pin Count | 28 | 28 | 28 | 28 | 28 | 28 |
| Lifecycle Status | NRND (Not Recommended for New Design) | NRND | NRND | NRND | NRND | NRND |
| Parameter Match (overall) | 100% (reference) | 100% | 90% | 90% | 80% | 80% |
Key Differentiators
- Modern ordering code without legacy '68HC' prefix (vs MC68HC908JL3ECDW (target))
- JK variant with similar package and FLASH (vs MC68HC908JK3ECDW)
- Internal-RC oscillator eliminates external crystal (vs MC68HRC908JL3ECDW)
Design Notes
Estimated: at 8 MHz / 5 V Vdd and HC08 active-mode current draw of ~7 mA typical, the MCU dissipates roughly 35 mW. The 28-SOIC package has a thermal resistance around 80 C/W, so junction temperature rise above ambient is on the order of 3 C - well within the industrial -40C to +85C range. Always include a 100 nF decoupling capacitor within 5 mm of each VDD/VSS pin pair.
Place the crystal or resonator as close as possible to OSC1/OSC2 and guard those pins with a ground ring to reduce EMI. Keep high-speed switching traces (relay drivers, TRIAC gates) at least 5 mm from the MCU oscillator area to avoid injection of noise into the timing reference. The 28-SOIC wide-body package allows wide PCB traces, simplifying low-cost two-layer designs.
Do not exceed the maximum rated Vdd; the HC08 JL3E datasheet documents a maximum Vdd of 6 V on the standard mask and 3.6 V on the HLC low-voltage mask. Leave the BDM (BKGD) pin either floating or pulled per NXP debug-port guidelines - never tied low in production or the device will appear stuck in active background mode. Finally, ensure the reset pin has a proper pull-up plus decoupling; floating RST can cause intermittent start-up faults.
Because the M68HC908JL3E family is NRND, second-source the BOM and qualify a fallback (e.g. the MC908JL3ECDWE listed in alternatives) before committing to a new design. Ensure your firmware build chain supports the BDM-based flash programming tool, not only in-circuit programming, because some older tools assume external EPROM-based debug.
Compliance Information
Verified Web Data did not list specific RoHS/REACH declarations for MC68HC908JL3ECDW. NXP/Freescale SOIC-package legacy parts are generally RoHS-compliant under original lead-free conversions, but a manufacturer-level declaration could not be confirmed from the provided snippets - set to 'unknown' to avoid fabrication. AEC-Q100 status explicitly not qualified for automotive safety-critical applications.
