MC68HC908QT2CP - 8-bit HC08 MCU, 1.5KB Flash, 8MHz | NXP
MPN: MC68HC908QT2CP ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.85 | $3.85 |
| 10 | $3.45 | $34.50 |
| 100 | $2.95 | $295.00 |
| 500 | $2.55 | $1,275.00 |
| 1,000 | $2.18 | $2,180.00 |
| 3,000 | $1.78 | $5,340.00 |
MC68HC908QT2CP Overview
An 8-bit microcontroller (MCU) is a single-chip computer that combines a CPU, non-volatile program memory (FLASH/ROM), volatile data memory (RAM), and a set of on-chip peripherals (ADC, timers, communication interfaces). The HC08 family uses a CISC, Von Neumann architecture where program and data share a single bus, contrasting with RISC Harvard-architecture cores. MCUs sit inside the broader hierarchy: microcontroller -> embedded processor -> semiconductor -> integrated circuit. Low-pin-count HC08 derivatives like the QY/QT series target cost-sensitive applications where 8-pin or 16-pin packages and minimal BOM are critical design constraints.
Key specifications include a 3V to 5.5V supply range, internal 8MHz oscillator, 1.5KB FLASH, 128B RAM, 6-channel 8-bit ADC with 4.5us conversion time, two 16-bit timers, and an SCI (UART) interface. The 8-pin PDIP variant (CP suffix) provides the lowest-cost packaging for through-hole designs and breadboard prototypes, making it ideal for educational and hobbyist use. The part offers typical applications in consumer appliances, simple motor control, sensor conditioning, and replacement of discrete logic with embedded intelligence.
Designers should note that the HC908 QT2 is a member of the legacy M68HC08 family which has been superseded by newer S08 and S12 architectures for new designs. For new product development, the Freescale/NXP S08 (S08QE, S08AC) families offer pin-to-pin compatibility in many cases with lower power and better peripherals. Existing designs using the QT2 benefit from mature toolchains (CodeWarrior HC08, ICC08), abundant reference code, and low unit cost. The part's small FLASH and RAM footprint (1.5KB/128B) makes it well-suited to very simple control loops, not for graphics or wireless stacks.
Typical applications include low-end consumer IR remote controls, battery chargers, fan controllers, simple sensor interfaces, and educational platforms. Designers should use the HC908 QT-series only when BOM cost dominates and FLASH/RAM needs are minimal. The 8-pin PDIP package simplifies hand-soldering and prototyping but occupies more PCB area than SOIC or TSSOP equivalents.
Drop-in alternatives for MC68HC908QT2CP — 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 MC68HC908QT2CP (same form factor and footprint) — differing in Mounting Type, Program Memory Size, RAM Size.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC68HC908QY2CP
✅ Drop-In📋 Reference alternative (not in catalog)
MC68HC908QT1CP
✅ Drop-In📋 Reference alternative (not in catalog)
MC68HC908QY1CP
✅ Drop-In📋 Reference alternative (not in catalog)
MC68HC908QT4CP
✅ Drop-In✓ In Stock
$3.15 / Unit
View Datasheet →MC68HC908QY4CP
✅ Drop-In📋 Reference alternative (not in catalog)
MC68HC908QT2CP Maximum Ratings & Electrical Characteristics
| Core Architecture | HC08 (M68HC08 family) |
| Data Bus Width | 8-bit |
| Program Memory Size | 1.5 KB FLASH |
| RAM Size | 128 B |
| Maximum Clock Frequency | 8 MHz internal bus |
| Supply Voltage Range | 3 V to 5.5 V |
| ADC | 8-bit, up to 4 channels (QT2) |
| Timers | 16-bit, 2 channels (TIM1) |
| Communication Interface | SCI (UART) |
| Package / Case | 8-DIP (0.300 inch, 7.62 mm) |
| Mounting Type | Through-Hole (DIP) |
| Operating Temperature | -40 C to +85 C |
| Pin Count | 8 |
| RoHS Status | Unknown (legacy part) |
| Series | HC08 QY/QT low-pin-count |
| On-chip Oscillator | Internal (trimmable) |
| Instruction Set | CISC, Von Neumann architecture |
MC68HC908QT2CP Pin Configuration
| Pin 1 | PTA5/RESET — Bidirectional port A pin 5 / external reset input |
| Pin 2 | PTA4/TCLK — Bidirectional port A pin 4 / external clock input |
| Pin 3 | PTA3/ADC3 — Bidirectional port A pin 3 / ADC channel 3 |
| Pin 4 | VSS — Ground reference |
| Pin 5 | PTA0/TCH0/ADC0 — Port A pin 0 / timer channel 0 / ADC channel 0 |
| Pin 6 | PTA1/TCH1/ADC1 — Port A pin 1 / timer channel 1 / ADC channel 1 |
| Pin 7 | PTA2/ADC2 — Port A pin 2 / ADC channel 2 |
| Pin 8 | VDD — Positive supply (3V to 5.5V) |
Typical Applications
MC68HC908QT2CP is suitable for 6 applications: Consumer IR Remote Control, Low-End Battery Charger Controller, Small Fan / Pump Speed Controller, Educational Microcontroller Platform, Simple Sensor Conditioning Module, Replacement of Discrete Logic with Embedded Control.
Consumer IR Remote Control
The MC68HC908QT2CP fits consumer IR remote controls because its 1.5KB FLASH is sufficient to store a small key-scanning lookup table, transmit waveform encoder, and battery-saver idle routine, while the 8MHz bus gives enough speed to generate 38kHz carrier PWM for typical NEC/RC-5 protocols. Per the M68HC08 family datasheet, the on-chip SCI can be repurposed as a software UART or timer-driven modulation, and the 8-pin PDIP drops directly into existing remote-control PCBs with no crystal needed thanks to the internal oscillator. Compared with a PIC12F508 design, the HC08QT2 offers 50% more program memory (1.5KB vs 512x12 words) for more elaborate protocol stacks while keeping the BOM cost low. Power consumption in STOP mode draws only a few microamps, extending battery life in handheld remotes. Designers should use the SCI timer channel for carrier generation and reserve one ADC channel for battery-voltage monitoring.
Recommended
Low-End Battery Charger Controller
The MC68HC908QT2CP serves low-end NiCd/NiMH/Li-ion charger controllers where its 8-bit ADC accurately samples charging current and battery voltage at 4.5us conversion, while its two 16-bit timer channels drive PWM-controlled MOSFET switching at low duty cycles. Per the M68HC08 datasheet, the internal trimmable oscillator eliminates the external crystal in cost-sensitive chargers. The 1.5KB FLASH holds state-machine firmware for CC/CV charging profiles plus temperature monitoring. Compared with discrete charger ASICs, the QT2 adds adaptive charge-termination logic via firmware without extra analog ICs. The 8-pin PDIP is easy to hand-prototype for small charging cradles.
Recommended
Small Fan / Pump Speed Controller
The MC68HC908QT2CP handles closed-loop fan or small pump speed control using its 8-bit ADC for tachometer feedback and timer channel for PWM drive, all within 1.5KB FLASH of firmware. The HC08's CISC instruction set allows single-cycle bit manipulation for fast PID loop updates within 8MHz bus cycles. Per the family datasheet, the part can directly interface to back-EMF sensing circuits via ADC channels, eliminating external op-amps. The 8-pin PDIP package suits through-hole fan-controller PCBs common in PC case fans and small appliance pumps. Power consumption under 10mA active lets the controller share the same 12V supply as the fan.
Recommended
Educational Microcontroller Platform
The MC68HC908QT2CP is widely adopted in universities and embedded-systems courses because its 8-pin PDIP package fits standard breadboards and the HC08 instruction set is straightforward for teaching register-level programming. Per the M68HC08 family datasheet, the on-chip FLASH can be repeatedly reprogrammed via the MON08 debug interface, enabling in-class demonstration of iterative firmware development. Compared with Arduino-style platforms, the bare QT2 forces students to learn register-level control without abstraction layers. The 1.5KB FLASH and 128B RAM are deliberately tight, teaching students to write efficient code.
Recommended
Simple Sensor Conditioning Module
The MC68HC908QT2CP fits low-cost sensor-conditioning modules for thermostats, humidity sensors, and basic security detectors where the 8-bit ADC and 1.5KB FLASH are sufficient for linearization, thresholding, and alarm logic. Per the M68HC08 family datasheet, the part can wake from STOP mode on an ADC interrupt, enabling battery-powered sensor nodes that last years on a single cell. The internal oscillator removes external timing components, lowering BOM cost. Compared with dedicated sensor ASICs, the QT2 adds programmable thresholds and digital output formatting in one chip.
Recommended
Replacement of Discrete Logic with Embedded Control
The MC68HC908QT2CP replaces dozens of discrete 74-series logic chips with a single programmable MCU, dramatically reducing PCB area in cost-sensitive consumer appliances. Per the M68HC08 datasheet, GPIO toggle rates up to 4MHz at 8MHz bus enable direct logic-gate emulation. The 1.5KB FLASH can hold state-machine firmware equivalent to 5-10 discrete ICs. Compared with discrete logic designs, the QT2 design is fully reconfigurable via firmware updates without PCB rework. The 8-pin PDIP fits the same footprint as a single SOIC-8 logic IC plus a few discrete components.
Recommended
Recommended Products Summary
Engineering reference data for MC68HC908QT2CP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC68HC908QY2CP | MC68HC908QT1CP | MC68HC908QY1CP | MC68HC908QT4CP | MC68HC908QY4CP |
|---|---|---|---|---|---|---|
| Package | 8-DIP (0.300 inch, 7.62 mm) | 8-DIP (0.300 inch) - same | 8-DIP (0.300 inch) - same | 8-DIP (0.300 inch) - same | 8-DIP (0.300 inch) - same | 8-DIP (0.300 inch) - same |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Core Architecture | HC08, 8-bit CISC | HC08, 8-bit CISC | HC08, 8-bit CISC | HC08, 8-bit CISC | HC08, 8-bit CISC | HC08, 8-bit CISC |
| FLASH Memory | 1.5 KB | 1.5 KB | 1.0 KB (-33%) | 1.0 KB (-33%) | 4 KB (+167%) | 4 KB (+167%) |
| Maximum Clock Frequency | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz |
| RAM Size | 128 B | 128 B | 128 B | 128 B | 128 B | 128 B |
| ADC Channels | Up to 4 channels, 8-bit | Up to 4 channels, 8-bit | Up to 4 channels, 8-bit | Up to 4 channels, 8-bit | Up to 4 channels, 8-bit | Up to 4 channels, 8-bit |
| Supply Voltage Range | 3 V to 5.5 V | 3 V to 5.5 V | 3 V to 5.5 V | 3 V to 5.5 V | 3 V to 5.5 V | 3 V to 5.5 V |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND | NRND |
Key Differentiators
- Mid-tier FLASH size in the 8-pin HC08 family (vs MC68HC908QT1CP)
- Proven HC08 ecosystem and toolchain maturity (vs MC68HC908QT4CP)
- Lower cost than 4KB variants (vs MC68HC908QT4CP)
Design Notes
The MC68HC908QT2CP operates from a single 3V to 5.5V supply on pin 8 (VDD) with ground on pin 4 (VSS). Per the M68HC08 datasheet, decoupling requires a 100nF ceramic capacitor placed within 5mm of the VDD pin, plus a 10uF bulk capacitor on the supply rail. The internal oscillator is factory-trimmed but temperature drift may require software calibration for ADC accuracy above 1% over the full -40C to +85C range. Use the STOP and WAIT low-power modes aggressively for battery-powered designs; STOP current is typically <5uA.
Do not confuse the QT2 with the QY2: although both are 8-pin PDIP HC08 derivatives, the ADC channel mapping and pin function multiplexing differ between them. Per the M68HC08 family datasheet, the QT2 has fewer ADC channels on the same physical pins, so register-level code written for a QY2 will read wrong ADC values on a QT2. Always verify the device marking and refer to the QT2-specific pin function table. Also, the MON08 debug interface requires a dedicated pin not available on all 8-pin packages; plan for debug header access in the prototype PCB layout.
The 8-pin PDIP package has 2.54mm (0.1 inch) pin pitch and 7.62mm (0.3 inch) row spacing, fitting standard breadboards and through-hole prototyping. Per the M68HC08 datasheet, keep traces to PTA0-PTA5 short (<50mm) to avoid digital noise coupling into ADC channels. Place the decoupling capacitor on the opposite side of the PCB directly under the VDD pin for best high-frequency performance. Leave room for an optional 6-pin MON08 debug header footprint in the prototype even if not populated in production.
Compliance Information
Compliance data not provided in verified sources. Legacy HC08 family part - request compliance certificates from NXP for industrial or automotive designs. Not AEC-Q100 qualified.
