MC68HC908QT4CFQ - 8-bit HC08 MCU, 4KB Flash | NXP
Teilenummer: MC68HC908QT4CFQ ✗ Abgekündigt| Menge | Stückpreis | Gesamt |
|---|---|---|
| 1 | $3.75 | $3,75 |
| 10 | $3.38 | $33,80 |
| 100 | $2.98 | $298,00 |
| 500 | $2.65 | $1.325,00 |
| 1.000 | $2.4 | $2.400,00 |
MC68HC908QT4CFQ Übersicht
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.
Drop-in-Alternativen für MC68HC908QT4CFQ – gleiches Gehäuse, Pin-kompatibel. Bauteile mit anderem Gehäuse, die eine PCB-Überarbeitung erfordern, sind ausgeschlossen.
Varianten dieser Serie
Modelle derselben Serie, die drop-in-kompatibel sind mit MC68HC908QT4CFQ (gleiche Bauform und Footprint) – abweichend in RAM Size, Mounting Type, Program Memory Size, Core Architecture, Package.
Schnellvergleichstool – Wählen Sie Alternativbauteile für den Direktvergleich:
MC908QT4ACFQE
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MC908QT2ACFQE
✅ Drop-In✓ Auf Lager
$0.65 / Stück
Datenblatt ansehen →MC908QT1ACFQE
✅ Drop-In✓ Auf Lager
$1.7 / Stück
Datenblatt ansehen →MC68HC908QT4CPE-FR
✅ Drop-In✓ Auf Lager
Preis auf Anfrage
Datenblatt ansehen →MC68HC908QT2CPE
✅ Drop-In📋 Referenzalternative (nicht im Katalog)
MC68HC908QY2CPE
✅ Drop-In✓ Auf Lager
$2.69 / Stück
Datenblatt ansehen →MC68HC908QT4CFQ Grenzwerte & elektrische Eigenschaften
| Core / Family | M68HC08 (HC08 CISC, Von Neumann) |
| Datenbusbreite | 8 bit |
| Program Memory Size | 4 KB Flash |
| RAM Size | 128 byte |
| Maximale Taktfrequenz | 8 MHz internal bus (family spec) |
| Versorgungsspannung | 3.3 V / 5 V (family: 2.7 V to 5.5 V) |
| Betriebstemperaturbereich | -40 C to +85 C (industrial, CFQ suffix) |
| Number of I/O Pins | 6 (8-pin package; 2 used for VDD/VSS) |
| Gehäuse | 8-pin HVQCCN / QFN-EP (4x4 mm) |
| Montageart | 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 |
MC68HC908QT4CFQ Pin-Konfiguration
| Pin 1 | PTB0/IRQ — General-purpose I/O PTB0 or external interrupt request input (family pinout per MC68HC908QY4 datasheet) |
| Pin 2 | VDD — Positive supply, 3.3 V or 5 V nominal |
| Pin 3 | VSS — Ground |
| Pin 4 | OSC1 — Crystal/resonator input or external clock source |
| Pin 5 | OSC2 — Crystal/resonator return or unused when external clock supplied |
| Pin 6 | RST — Active-low external reset input |
| Pin 7 | PTA0/TCH0 — General-purpose I/O PTA0 or Timer Channel 0 (16-bit timer capture/compare) |
| Pin 8 | PTA1 — General-purpose I/O PTA1 |
Typische Anwendungen
MC68HC908QT4CFQ ist geeignet für 7 Anwendungs: 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.
Empfohlen
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.
Empfohlen
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.
Empfohlen
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.
Empfohlen
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.
Empfohlen
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.
Empfohlen
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.
Empfohlen
Zusammenfassung der empfohlenen Produkte
Technische Referenzdaten für MC68HC908QT4CFQ – Vergleich, Designhinweise und Compliance-Informationen.
Auswahlhilfe
Vergleich mit Alternativen
| Parameter | Dieses Produkt | 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 |
Wichtigste Unterscheidungsmerkmale
- Largest Flash in legacy QT/QY 8-pin lineup (vs. MC908QT2ACFQE)
- Pb-free 8-pin QFN-EP for reflow production (vs. MC68HC908QT4CPE)
- Industrial temperature with same HC08 toolchain (vs. MC908QT1ACFQE)
Designhinweise
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.
Compliance-Informationen
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.
