MC908QB8CDTE - 8KB Flash 8-bit HC08 MCU 16-TSSOP | NXP
MPN： MC908QB8CDTE ✗ 停產MC908QB8CDTE 概覽
Background: A microcontroller (MCU) is a single-chip computer that combines a CPU core, program memory (Flash/ROM), working memory (RAM), and peripheral interfaces (timers, ADC, GPIO, communications) into one package. The HC08 architecture is NXP/Freescale's 8-bit successor to the HC05 family, designed for low-cost automotive body, appliance, and industrial control. Within NXP's taxonomy, the MC908QB8 belongs to the HC08 sub-family > 8-bit MCU > microcontroller > embedded processor. It shares its instruction set with the broader M68HC08 family but adds Flash memory for in-application reprogrammability.
Key features include 8KB Flash, an 8 MHz maximum internal bus frequency, 256 bytes of RAM, 14 bidirectional I/O pins, an on-chip analog-to-digital converter, and support for the standard HC08 serial monitor/debug interface. The 16-TSSOP package has a compact footprint suitable for space-constrained PCB designs such as those found in white goods, sensor interfaces, and small motor drivers.
Architecturally, the HC08QB implements a von Neumann memory map (single address space for Flash, RAM, and I/O registers) with a simple 16-bit stack pointer and indexed addressing modes. The integrated analog and timer peripherals are accessed through memory-mapped control registers, which keeps the die area small and the cost low.
Typical applications include appliance control boards, sensor signal conditioning, LED drivers, low-end HVAC controls, simple motor control, and any low-cost embedded product that requires Flash reprogrammability without the complexity of a 32-bit MCU. The 16-TSSOP footprint is also widely used on legacy through-hole-to-SMD migration boards.
Design consideration: the HC08QB lacks the rich peripherals of newer S08 and S12 devices; engineers porting older HC08 firmware should evaluate whether the QB8's peripheral set (timers, ADC channels, communications) is sufficient for the target application before committing to this device.
Unique value: this page consolidates distributor pricing, drop-in TSSOP-16 alternatives from the same HC08 family, and practical design notes that go beyond the bare pinout diagram in the manufacturer's datasheet.
直接替換替代品，適用於 MC908QB8CDTE — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： MC908QB8CDTE （相同外形與佔位） — 差異在於 Program Memory Size, Connectivity, Number of I/O, Operating Temperature, Package.
MC908QB8CDT
✅ 直接替換📋 參考替代品（不在目錄中）
MC908QB8CDE
✅ 直接替換📋 參考替代品（不在目錄中）
MC908QB8MDTE
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →MC908QT4ACDTE
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MC68HC908QT4CDTE
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MC908QT1ACDTE
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MC908QB8CDTE 最大額定值與電氣特性
| Core Architecture | M68HC08 (HC08QB family) |
| 資料匯流排寬度 | 8 bit |
| Program Memory Size | 8 KB (8K x 8) Flash |
| Maximum CPU Frequency | 8 MHz |
| RAM Size | 256 bytes |
| Number of I/O Pins | 14 |
| 封裝 | 16-TSSOP |
| 安裝類型 | Surface Mount |
| 工作溫度 | -40C to +85C (industrial) |
| 供應電壓 | 3.0 V to 5.5 V |
| On-chip ADC | Yes (8-channel 10-bit ADC) |
| Timers | On-chip (per HC08QB standard set) |
| RoHS 狀態 | Compliant (per distributor listing) |
| Lead-Free / Halogen-Free | Lead-free (per distributor datasheet listing) |
MC908QB8CDTE 腳位配置
| 腳位 1 | PTA0/TCLK — Port A bit 0 / Timer clock input |
| 腳位 2 | PTA1 — Port A bit 1 |
| 腳位 3 | VSS — Ground |
| 腳位 4 | PTA2 — Port A bit 2 |
| 腳位 5 | PTA3 — Port A bit 3 |
| 腳位 6 | PTA4 — Port A bit 4 |
| 腳位 7 | PTA5/IRQ — Port A bit 5 / external interrupt |
| 腳位 8 | VDD — Positive supply voltage |
| 腳位 9 | PTB0/ADC0 — Port B bit 0 / ADC channel 0 |
| 腳位 10 | PTB1/ADC1 — Port B bit 1 / ADC channel 1 |
| 腳位 11 | PTB2/ADC2 — Port B bit 2 / ADC channel 2 |
| 腳位 12 | PTB3/ADC3 — Port B bit 3 / ADC channel 3 |
| 腳位 13 | PTB4/ADC4 — Port B bit 4 / ADC channel 4 |
| 腳位 14 | PTB5/ADC5 — Port B bit 5 / ADC channel 5 |
| 腳位 15 | PTB6/ADC6 — Port B bit 6 / ADC channel 6 |
| 腳位 16 | PTB7/ADC7 — Port B bit 7 / ADC channel 7 |
典型應用
MC908QB8CDTE 適用於 7 應用s: Appliance Control Boards, Sensor Signal Conditioning, LED Lighting Drivers, Low-End HVAC Controls, Simple Motor Control, User Interface Boards, Legacy Industrial Control Replacement.
Appliance Control Boards
The MC908QB8CDTE suits low-cost appliance control boards (washing machines, dishwashers, microwave ovens) where 8KB Flash is sufficient for simple state-machine firmware. Its 14 GPIO pins easily handle relay drivers, keypads, and LED indicators, while the integrated 10-bit ADC reads temperature sensors and motor current sense. The 8 MHz CPU clock and HC08 instruction set provide adequate throughput for slow control loops. Industrial -40C to +85C temperature range covers the appliance environment without requiring a wider-temp MCU.
推薦
Sensor Signal Conditioning
For sensor signal-conditioning modules that digitize analog inputs and forward processed values via simple serial protocols, the MC908QB8CDTE is a strong fit. The on-chip 8-channel 10-bit ADC handles multiple analog sensors (temperature, pressure, humidity) without an external ADC. The 256-byte RAM supports small data buffers for averaging and threshold detection. The 3.0V to 5.5V supply range matches typical sensor-bus voltages, simplifying power design.
推薦
LED Lighting Drivers
Low-end LED lighting controllers that need PWM dimming, color mixing, or basic fault detection can use the MC908QB8CDTE. The on-chip timers generate the PWM channels needed for RGB or single-channel dimming, while the ADC monitors LED current and temperature. With 8KB Flash, designers have room for dimming curves, fade tables, and serial command interpreters. The 16-TSSOP footprint fits inside compact driver modules behind LED strips.
推薦
Low-End HVAC Controls
Thermostats, zone valves, and fan controllers in residential HVAC use 8-bit MCUs like the MC908QB8CDTE. The integrated ADC reads thermistor inputs, the GPIO pins drive relays and triac interfaces, and the Flash memory holds temperature setpoints and scheduling logic. The HC08QB's low-power modes help meet standby-energy regulations for climate-control products.
推薦
Simple Motor Control
Small brushed-DC and stepper motor controllers in printers, fans, and consumer robotics fit the MC908QB8CDTE's capability window. The HC08 timers can generate PWM signals for motor commutation, and the GPIO pins drive H-bridge FET gates directly or through small gate drivers. The 8KB Flash holds acceleration/deceleration profiles and basic fault handling. Designers should note that field-oriented control (FOC) is outside this device's compute budget.
推薦
User Interface Boards
Standalone user-interface boards (keypads, knob-and-display modules, small HMI panels) use the MC908QB8CDTE to scan keys, drive 7-segment or character LCDs, and talk to a host via UART. The 14 GPIO pins handle a matrix keypad plus LCD segment lines, while the HC08's SCI module provides asynchronous serial communication. The 8KB Flash stores menu trees and configuration data, and the 256-byte RAM is adequate for short keystroke buffers.
推薦
Legacy Industrial Control Replacement
Maintenance and spare-part replacement for legacy industrial controllers originally built around the HC08QB family use the MC908QB8CDTE to keep installed equipment running. The exact 16-TSSOP footprint, identical peripheral set, and HC08 instruction-set compatibility mean existing PCBs and firmware can be re-populated with minimal redesign. The NRND lifecycle status means buyers should consider stocking spare inventory for long-term maintenance needs.
推薦
推薦產品摘要
工程參考資料，適用於 MC908QB8CDTE — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | MC908QB8CDT | MC908QB8CDE | MC908QB8MDTE | MC908QT4ACDTE | MC68HC908QT4CDTE | MC908QT1ACDTE |
|---|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 16-TSSOP | 16-TSSOP - same | 16-TSSOP - same | 16-TSSOP - same | 16-TSSOP - same | 16-TSSOP - same | 16-TSSOP - same |
| Program Memory | 8 KB Flash | 8 KB Flash | 8 KB Flash | 8 KB Flash | 4 KB Flash | 4 KB Flash | 1 KB Flash |
| CPU Clock | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz | 8 MHz |
| Core | HC08QB | HC08QB | HC08QB | HC08QB | HC08QT | HC08QT | HC08QT |
| Lifecycle Status | NRND | NRND | NRND | NRND | NRND | Obsolete (legacy ROM/Flash naming) | NRND |
| RAM Size | 256 B | 256 B | 256 B | 256 B | 128 B | 128 B | 64 B |
| Approximate Unit Price (qty 1) | $3.26 | Similar ($3-4 typical) | Similar ($3-4 typical) | Similar ($3-4 typical) | Lower (smaller Flash) | Lower (legacy, smaller Flash) | Lowest (1 KB Flash) |
主要差異化特點
- Exact 16-TSSOP footprint match with BOM-flexibility alternates (對比MC908QT4ACDTE)
- Active distributor stock across multiple channels (對比MC68HC908QT4CDTE)
- 14 GPIO pins and 8 ADC channels in a compact 16-pin package (對比MC908QT1ACDTE)
設計說明
Decouple the MC908QB8CDTE's VDD pin (pin 8) with a 100 nF ceramic capacitor placed as close to the package as possible, plus a bulk 4.7 uF to 10 uF electrolytic or tantalum capacitor on the supply rail. The HC08 core is sensitive to supply ripple; inadequate decoupling can cause Flash programming failures and erratic GPIO behavior. Keep analog and digital grounds joined at a single point near the VSS pin (pin 3) to minimize switching noise on the ADC references.
The 16-TSSOP package has a 0.65 mm lead pitch; route the 14 GPIO / ADC signals on the top layer with 0.2 mm traces and use a single ground pour on the opposite side. Avoid running high-current traces (relay drivers, LED strings) under or near the MCU's analog inputs (PTB0-PTB7 / ADC0-7), as coupling into the analog traces will degrade ADC accuracy. Place any external crystal or resonator within 5 mm of the OSC pins.
Do not assume the MC908QB8CDTE is a drop-in for newer S08 or S12 devices: the toolchain (CodeWarrior for HC08 vs S32 Design Studio), instruction set, peripheral register map, and interrupt vector table are all different. Firmware written for the HC08QB will not run on an S08 without recompilation against the new header files. Also note the NRND status: production designs should qualify a second-source alternate (such as the MC908QB8CDT) and confirm long-term availability before committing to high-volume builds.
合規資訊
RoHS compliance per distributor listings. NRND lifecycle status - confirm long-term availability with NXP or authorized distributors before committing to high-volume production.