MC68HC908QT4CFQ - 8-bit HC08 MCU, 4KB Flash | NXP
MPN: MC68HC908QT4CFQ ✗ Cuối đờiMC68HC908QT4CFQ Tóm tắt
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, program memory, data RAM, and I/O peripherals on one silicon die; HC08 denotes the CMOS process generation of the classic Motorola 68HC05/68HC08 family, using a Von Neumann (single bus) CISC architecture with a uniform 16-bit address space shared between program and data. The MC68HC908QT4 belongs to the low-cost, high-performance M68HC08 family and is engineered as a small-footprint member optimized for appliance, sensor-interface, and remote-control use cases where a full QFP package would be wasteful.
Key features include 4 KB of Flash program memory with in-system programmability via the standard Motorola monitor mode, 128 bytes of RAM, an internal oscillator that supports an external crystal or resonator, a 16-bit timer with capture/compare, and a multi-channel 8-/10-bit ADC on related QT/QY family devices. The CFQ suffix specifies the industrial temperature range and lead-free terminal finish (Pb-free, no-lead, HVQCCN).
The architecture combines a HC08 CPU with a security/breakpoint ROM, a SIM (System Integration Module) for clock, reset, and interrupt control, and a FLASH memory array configured as 4 pages of 1 KB each, with an internal 96-byte monitor ROM (per the family datasheet) reserved for factory test and serial in-application programming. The 68HC908 QT/QY family is software-compatible with the 68HC05 instruction set plus a few added addressing modes.
Typical applications include low-end remote controls, small appliance controllers, battery chargers, LED driver controllers, simple sensors and monitoring nodes, and any space-constrained design that needs a genuine general-purpose MCU rather than a specialized fixed-function controller. Designers also use the QT/QY family for product variants where different memory sizes (1 KB, 2 KB, 4 KB) are binned from the same die to simplify supply chain. When laying out a QT-board, route the exposed thermal pad of the QFN-EP to a grounded copper pour, allocate one PCB edge for programming/debug access (the standard QY/QT family uses single-wire background debug mode plus an external IRQ pin), and respect the OSC1/OSC2 routing guidance in the family datasheet.
This page synthesizes distributor pricing, same-family NXP and Freescale drop-in alternatives, and practical design notes not found in a single distributor search.
Bộ thay thế dễ dàng lắp đặt cho MC68HC908QT4CFQ — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với MC68HC908QT4CFQ (cùng hình factor và footprint) — khác nhau ở RAM Size, Mounting Type, Program Memory Size, Core Architecture, Package.
MC908QT4ACFQE
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC908QT2ACFQE
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC908QT1ACFQE
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC68HC908QT4CPE-FR
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC68HC908QT2CPE
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
MC68HC908QY2CPE
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →MC68HC908QT4CFQ Tỷ lệ tối đa & tính chất điện
| Core / Family | M68HC08 (HC08 CISC, Von Neumann) |
| Bề rộng đường dữ liệu | 8 bit |
| Program Memory Size | 4 KB Flash |
| RAM Size | 128 byte |
| Tần số xung maksimum | 8 MHz internal bus (family spec) |
| Điện áp cung cấp | 3.3 V / 5 V (family: 2.7 V to 5.5 V) |
| Khoảng nhiệt độ hoạt động | -40 C to +85 C (industrial, CFQ suffix) |
| Number of I/O Pins | 6 (8-pin package; 2 used for VDD/VSS) |
| Hộp | 8-pin HVQCCN / QFN-EP (4x4 mm) |
| Kiểu lắp đặt | Surface Mount |
| Terminal Finish | Pb-free, no-lead (CFQ suffix) |
| ADC | 8-/10-bit ADC included in family (consult datasheet) |
| Timers | 16-bit timer with capture/compare (family) |
| Programming Interface | Background Debug Mode (single-wire); in-circuit programming |
| Lead Free / RoHS | Pb-free per CFQ terminal finish |
Cấu hình chân MC68HC908QT4CFQ
| Chân 1 | PTB0/IRQ — General-purpose I/O PTB0 or external interrupt request input (family pinout per MC68HC908QY4 datasheet) |
| Chân 2 | VDD — Positive supply, 3.3 V or 5 V nominal |
| Chân 3 | VSS — Ground |
| Chân 4 | OSC1 — Crystal/resonator input or external clock source |
| Chân 5 | OSC2 — Crystal/resonator return or unused when external clock supplied |
| Chân 6 | RST — Active-low external reset input |
| Chân 7 | PTA0/TCH0 — General-purpose I/O PTA0 or Timer Channel 0 (16-bit timer capture/compare) |
| Chân 8 | PTA1 — General-purpose I/O PTA1 |
Ứng dụng tiêu biểu
MC68HC908QT4CFQ phù hợp cho 7 Áp dụngs: Remote Control Transmitter, Small Appliance Controller, Battery Charger / Power Management Slave, Sensor Signal-Conditioning Node, LED Lighting Controller, Automotive Accessory Controller (Non-Safety), Security Keypad / Panel.
Remote Control Transmitter
The MC68HC908QT4CFQ fits remote control transmitters because its 4 KB of Flash is enough for fixed-format PWM/IR encoders with table-driven button mappings, while the 8-pin QFN-EP 4x4 mm package fits inside a slim plastic housing. The 6 available I/O (after VDD/VSS) accept a 4x4 keypad matrix plus an IR LED driver pin via the 16-bit timer PWM. Quiescent current at the 3.3 V option supports months of standby from alkaline cells, and the HC08's deterministic interrupt latency ensures glitch-free IR frames. Sourcing via NXP's franchise channels plus Rochester Electronics gives 5-10 year continuity for inventory-bound SKUs.
Được đề xuất
Small Appliance Controller
For appliances such as blenders, fans, and small kitchen devices, the MC68HC908QT4CFQ serves as a control MCU where its 128 B RAM holds motor-state flags and timers, the 16-bit capture/compare drives TRIAC or PWM outputs, and the internal oscillator eliminates an external resonator to save 30-50 cents on BOM. The CFQ industrial -40 C to +85 C temperature range covers consumer plus light-industrial installations, and the HC08's short interrupt latency is adequate for closed-loop motor control at low rpm. The 4 KB Flash supports boot, button-scan, and a simple safety-fault state machine.
Được đề xuất
Battery Charger / Power Management Slave
In a battery charger the MC68HC908QT4CFQ can act as the LED/display slave controller, offloading LED driving and button handling from the main fuel-gauge MCU. Its 3.3 V operation matches single-cell Li-ion rails, and the 8-bit ADC (within the QY/QT family context) reads cell voltage through a resistor divider. The Flash-based architecture supports firmware updates for charging-curve revisions without hardware rework. Pair the QT4 with a secondary protection IC and a coulomb counter to keep the BOM under $1.50 in volume.
Được đề xuất
Sensor Signal-Conditioning Node
Industrial and HVAC sensors benefit from the MC68HC908QT4CFQ because its 8-bit HC08 core plus on-board ADC (within the QY/QT family) provides sensor linearization with no extra DSP. The 128 B RAM is sized for slow-moving temperature or pressure data at sample rates under 100 Hz. Industrial temperature rating plus Pb-free QFN-EP lets the same board pass both consumer and factory-floor validation. Designers use the Flash to store calibrated coefficients, avoiding analog trim pots.
Được đề xuất
LED Lighting Controller
The MC68HC908QT4CFQ drives simple constant-current LED controllers from its 16-bit PWM channel, with software fade tables fitting comfortably within 4 KB Flash. The 8-pin QFN-EP occupies minimal PCB area behind the LED module, and the 3.3 V option eliminates a regulator when the LED string runs at higher voltage. Industrial temperature supports outdoor luminaires with conformal coating. For RGBW variants, switch to a sister QY device with more timer channels.
Được đề xuất
Automotive Accessory Controller (Non-Safety)
Although the MC68HC908QT4CFQ is not AEC-Q100 qualified, it is used in non-safety automotive accessories such as interior trim lighting or fan-speed controls where the industrial -40 C to +85 C rating covers cabin environments. The 4 KB Flash stores delay and fade profiles for lighting effects, and the HC08's short interrupt latency reacts to CAN-monitor inputs in well under 100 us. For safety-critical automotive nodes, migrate to the AEC-Q100 variants in the Kinetis E family.
Được đề xuất
Security Keypad / Panel
A door keypad or alarm panel can use the MC68HC908QT4CFQ as the entry-tier controller, scanning a 3x4 or 4x4 matrix through its 6 I/O pins and playing chirp audio through a piezo buzzer via PWM. Flash holds the PIN-vault state machine and the alarm-cycle logic. The HC08's deterministic interrupt latency reacts to tamper lines within microseconds, and the Flash in-application programming enables over-the-wire firmware patches via a service-mode pin. Use the larger QY sister for crypto-secured variants.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho MC68HC908QT4CFQ — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | MC908QT4ACFQE | MC908QT2ACFQE | MC908QT1ACFQE | MC68HC908QT4CPE | MC68HC908QT2CPE | MC68HC908QY2CPE |
|---|---|---|---|---|---|---|---|
| Package | 8-pin HVQCCN (QFN-EP) 4x4 mm | 8-pin HVQCCN (QFN-EP) 4x4 mm - same | 8-pin HVQCCN (QFN-EP) 4x4 mm - same | 8-pin HVQCCN (QFN-EP) 4x4 mm - same | 8-pin PDIP (DIP-8) | 8-pin PDIP (DIP-8) | 8-pin PDIP (DIP-8) |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Flash Memory | 4 KB | 4 KB | 2 KB (-50%) | 1 KB (-75%) | 4 KB | 2 KB (-50%) | 2 KB (-50%) |
| RAM | 128 B | 128 B | 128 B | 128 B | 128 B | 128 B | 128 B |
| Core / Family | HC08, 8-bit CISC | HC08, 8-bit CISC | HC08, 8-bit CISC | HC08, 8-bit CISC | HC08, 8-bit CISC | HC08, 8-bit CISC | HC08, 8-bit CISC |
| Supply Voltage | 3.3 V / 5 V (2.7-5.5 V family) | 3.3 V / 5 V (2.7-5.5 V family) | 3.3 V / 5 V (2.7-5.5 V family) | 3.3 V / 5 V (2.7-5.5 V family) | 3.3 V / 5 V (2.7-5.5 V family) | 3.3 V / 5 V (2.7-5.5 V family) | 3.3 V / 5 V (2.7-5.5 V family) |
| Operating Temperature | -40 C to +85 C (industrial) | -40 C to +85 C (industrial) | -40 C to +85 C (industrial) | -40 C to +85 C (industrial) | -40 C to +85 C (industrial) | -40 C to +85 C (industrial) | -40 C to +85 C (industrial) |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND | NRND | NRND |
Bảo phân biệt quan trọng
- Largest Flash in legacy QT/QY 8-pin lineup (vsMC908QT2ACFQE)
- Pb-free 8-pin QFN-EP for reflow production (vsMC68HC908QT4CPE)
- Industrial temperature with same HC08 toolchain (vsMC908QT1ACFQE)
Ghi chú thiết kế
The 4x4 mm HVQCCN (QFN-EP) package routes the entire electrical ground through the exposed thermal pad on the bottom of the part, so it MUST be soldered to a grounded copper pour that contains thermal vias to the inner/inner plane. A missing or starved thermal pad will raise the part's junction temperature by 20-40 C in bench tests and can also cause intermittent logic errors. Use NSMD pads with about 8 thermal vias arranged on a 1 mm pitch to keep the inductance path low; recommended copper pour area is at least 1 cm^2 on the top layer plus parallel pour on the bottom.
The HC08 QT/QY family uses Background Debug Mode (BDM) rather than the older HC05 monitor, so a legacy HC05 programming pod will not talk to a QT4 board. For production programming, pick a P&E Micro USB-ML or standalone Cyclone programmer and verify the latest firmware supports the MC68HC908QY4 family; an unsupported pod appears as if the Flash is read-only. Plan to add the BDM header or test pads early in PCB layout so engineering can reach the part without depackaging.
Add a 100 nF bypass capacitor within 5 mm of VDD (pin 2) and a 10 uF bulk capacitor near the VDD/VSS pair on every board, even though the QT family's internal bus speed tops out around 8 MHz. The internal ADC analog supply input (within the QY family context) needs a quiet rail; if the application sources VDD from a switching regulator, place a ferrite bead and a 10 uF low-ESR cap to prevent ADC noise pickup. For battery-powered designs, gate any unused oscillator and timer peripherals through the SIM module to drop quiescent current by 30-50%.
At 3.3 V with full GPIO switching at 8 MHz internal bus, the QT4 self-heats only minimally (estimated: <100 mW total), but in sealed modules without airflow, junction temperature can still exceed ambient by 10-15 C. For prolonged high-temperature operation (e.g., outdoor lighting, automotive cabin), place the part near a PCB edge where air can flow, or stitch vias through the exposed pad to inner copper layers. Estimated: at 25 C ambient with 1 oz copper pours on both sides, theta_JA approximates 60-80 C/W - well within safe limits for industrial-grade variants.
Thông tin tuân thủ
CFQ suffix indicates a Pb-free, no-lead (HVQCCN / QFN-EP) terminal finish per the family datasheet. The part is industrial -40 C to +85 C graded, not AEC-Q100 qualified. Reach, halogen-free, and conflict-minerals declarations were not in the brief web excerpts; request an IPC-1752 materials declaration from NXP or Rochester Electronics for compliance documentation. CPNP/IPC standards cited: JEDEC JESD22 moisture sensitivity, J-STD-020 reflow profile for the Pb-free QFN.
