MC9RS08KB4CSG - 8-bit RS08 MCU, 4KB Flash, 20MHz | NXP
MPN： MC9RS08KB4CSG ✓ 啟用中MC9RS08KB4CSG 概覽
An 8-bit microcontroller is a single-chip computer that integrates a CPU, memory (Flash/RAM), and peripherals onto one silicon die. The RS08 core is a reduced-instruction-set variant of the HC08 core, offering a subset of the HC08 instruction set plus a BGND (background debug) instruction. The RS08KB sits within the broader taxonomy of 8-bit MCU -> microcontroller -> embedded processor -> semiconductor device. By keeping competitive low-cost, low-power 8-bit controllers, NXP targets white goods, simple sensors, and battery-operated devices where 32-bit Cortex-M MCUs would be overkill.
Key features of the MC9RS08KB4CSG include 4KB (4K x 8) of program Flash, 126 bytes of RAM, an integrated analog-to-digital converter (ADC), timers, a serial communications interface (SCI), and an inter-integrated circuit (I2C) module. The device also includes an internal clock source, multiple I/O pins, and a low-power stop mode for energy-constrained designs. Its 5V tolerance and rugged I/O make it well suited for industrial and appliance environments.
The RS08KB family eases migration by offering multiple package and flash size options, along with pin compatibility across other 5-volt NXP families and support for the CodeWarrior development toolchain. Compared with more powerful ColdFire or Kinetis ARM Cortex-M parts, the RS08 is intentionally lean: one global interrupt vector, fewer addressing modes, and reduced register file, all of which reduce die cost and code size for simple control loops.
Typical applications for the MC9RS08KB4CSG include home appliances (washing machine user interfaces, microwave control panels), battery chargers, LED drivers, low-end toys, simple sensor signal conditioning, and small consumer electronics that require reliable 5V-tolerant digital control. The 20MHz CPU provides ample headroom for basic motor control loops, PWM generation, and UART-based communication with companion chips.
When designing with this MCU, ensure the supply rail stays within 2.7V to 5.5V and respect absolute-maximum ratings on I/O pins. For applications that outgrow 4KB Flash, the family offers pin-compatible higher-density variants (KB8, KB12) and migration paths to the S08 and Kinetis families with the same peripheral IP and toolchain.
This page combines verified distributor pricing, same-brand drop-in alternatives, and practical design notes not aggregated on the manufacturer product page.
直接替換替代品，適用於 MC9RS08KB4CSG — 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： MC9RS08KB4CSG （相同外形與佔位） — 差異在於 ADC, Timers.
MC9RS08KB8CSG
✅ 直接替換📋 參考替代品（不在目錄中）
MC9RS08KB12CSG
✅ 直接替換📋 參考替代品（不在目錄中）
MC9RS08KA4CWGR
✅ 直接替換📋 參考替代品（不在目錄中）
MC9RS08KA8CWG
✅ 直接替換聯絡詢價
查看資料表 →MC9RS08KB4CFK
✅ 直接替換📋 參考替代品（不在目錄中）
MC9RS08KB4CSG 最大額定值與電氣特性
| Core | RS08 (subset of HC08 instruction set) |
| 資料匯流排寬度 | 8 bit |
| Program Memory Size | 4 KB (4K x 8) Flash |
| RAM Size | 126 byte |
| Maximum CPU Frequency | 20 MHz |
| Supply Voltage Range | 2.7 V to 5.5 V |
| 工作溫度範圍 | -40 C to +85 C |
| Number of I/O Pins | 14 (typical for 16-SOIC) |
| Package Type | 16-SOIC (SOT-109 equivalent) |
| 安裝方式 | Surface Mount |
| ADC | Yes (integrated, multi-channel) |
| Timers | Yes (integrated) |
| Communication Interfaces | SCI (UART), I2C |
| Interrupt Controller | Single global interrupt vector |
| Low-Power Modes | Stop / Wait modes |
| Internal Clock | Yes (integrated oscillator) |
| Lead-Free / RoHS | Yes (details to follow manufacturer declaration) |
MC9RS08KB4CSG 腳位配置
| 腳位 1 | VDD — Positive supply voltage (2.7V to 5.5V) |
| 腳位 2 | PTA0/TCLK/ADP0 — Port A bit 0; timer clock input; ADC channel 0 |
| 腳位 3 | PTA1/ADP1 — Port A bit 1; ADC channel 1 |
| 腳位 4 | PTA2/ADP2 — Port A bit 2; ADC channel 2 |
| 腳位 5 | PTA3/ADP3 — Port A bit 3; ADC channel 3 |
| 腳位 6 | PTA4/ADP4 — Port A bit 4; ADC channel 4 |
| 腳位 7 | PTA5/ADP5 — Port A bit 5; ADC channel 5 |
| 腳位 8 | PTA6/ADP6 — Port A bit 6; ADC channel 6 |
| 腳位 9 | PTA7/ADP7 — Port A bit 7; ADC channel 7 |
| 腳位 10 | PTB0/SDA — Port B bit 0; I2C SDA |
| 腳位 11 | PTB1/SCL — Port B bit 1; I2C SCL |
| 腳位 12 | PTB2/TXD — Port B bit 2; SCI UART TXD |
| 腳位 13 | PTB3/RXD — Port B bit 3; SCI UART RXD |
| 腳位 14 | PTB4 — Port B bit 4; general-purpose I/O |
| 腳位 15 | PTB5/RESET — Port B bit 5; external reset input (bidirectional) |
| 腳位 16 | VSS — Ground reference |
典型應用
MC9RS08KB4CSG 適用於 6 應用s: Home Appliance User Interface, Battery Charger Controller, Low-End Toy and Hobby Electronics, Simple Sensor Signal Conditioning, LED Driver and Lighting Control, Small Consumer Electronics.
Home Appliance User Interface
The MC9RS08KB4CSG is well suited to drive the user-interface logic of white-goods appliances such as washing machines, microwave ovens, and dishwashers. Its 4KB Flash comfortably holds state-machine code for button debouncing, rotary-encoder reading, 7-segment or LED-matrix displays, and simple buzzer patterns. The 5V-tolerant I/O eliminates level shifters when interfacing with mechanical switches, triac (2N6075A) zero-cross detectors, and legacy LED driver transistors. The RS08 core's 20MHz headroom is sufficient for keypad scanning at 10ms rates and UART communication with a companion motor-control board. Compared with a 32-bit MCU, the KB4 reduces BOM cost while retaining deterministic interrupt latency for power-line-synchronized control.
推薦
Battery Charger Controller
For low-power NiMH or single-cell Li-ion chargers, the MC9RS08KB4CSG provides the ADC channels needed to measure battery voltage and charge current while running a simple CC-CV control loop in firmware. The integrated timers generate PWM for a buck or linear-pass regulator, and the SCI/UART reports charge-state telemetry to a host display. Stop and Wait low-power modes let the MCU draw microamps when the charger is idle on the shelf. The wide 2.7V-5.5V supply range allows direct operation from a USB 5V rail or a 3.3V regulated output without additional level shifting, simplifying the charger BOM.
推薦
Low-End Toy and Hobby Electronics
Toy RC controllers, motorized model accessories, and educational STEM kits benefit from the MC9RS08KB4CSG's low unit cost and modest 4KB Flash footprint, which is enough for PWM motor drive, simple sound playback patterns, and LED animations. The RS08 core's single global interrupt vector is well matched to the event-driven nature of toy firmware, and the 20MHz clock supports smooth servo-update rates. I2C lets the KB4 drive a small OLED or RGB-LED module, while the SCI/UART handles IR or 2.4GHz companion-radio links. The industrial -40C to +85C temperature range survives drops in a child's toy box.
推薦
Simple Sensor Signal Conditioning
Industrial and building-automation sensor nodes that only need to digitize one or two analog channels and forward readings over UART or I2C fit the MC9RS08KB4CSG perfectly. The on-chip ADC with internal voltage reference converts thermocouple-amplified, thermistor-bridge, or 4-20mA-derived voltages to digital counts, and the SCI/UART or I2C peripheral transmits the result to a higher-tier controller. The 5V-tolerant digital I/O can directly drive optocoupler-isolated outputs to industrial field buses. Compared with a full-featured MCU, the KB4 reduces idle current and unit cost while keeping deterministic response time on the slow sensor-update loop.
推薦
LED Driver and Lighting Control
LED strip drivers, under-cabinet lighting, and architectural dimmer controllers use the MC9RS08KB4CSG to generate PWM dimming waveforms, read rotary or capacitive touch inputs, and run smooth fade algorithms. The 20MHz CPU comfortably runs a 16-bit PWM at 9-bit resolution for flicker-free dimming down to 0.1 percent. The RS08KB's stop mode enables deep standby between user interactions, and wake-up via a single GPIO keeps average current low for battery-powered fixtures. The wide supply range allows operation from 12V LED-driver rails through a small linear regulator.
推薦
Small Consumer Electronics
Small consumer products such as electronic thermometers, kitchen scales, remote-control key fobs, and personal-care devices use the MC9RS08KB4CSG as a cost-optimized controller for simple button-driven state machines. The integrated ADC reads sensor elements, the timers drive piezo buzzers and LED indicators, and the SCI/UART offers a debug path for production test. The 16-SOIC package is hand-solderable for prototypes and short-run production, while the CodeWarrior toolchain shortens firmware development for engineers familiar with the HC08 ecosystem.
推薦
推薦產品摘要
工程參考資料，適用於 MC9RS08KB4CSG — 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 | MC9RS08KB8CSG | MC9RS08KB12CSG | MC9RS08KA4CWGR | MC9RS08KA8CWG | MC9RS08KB4CFK |
|---|---|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 16-SOIC | 16-SOIC | 16-SOIC | 16-SOIC | 16-SOIC | 16-SOIC |
| Core | RS08 | RS08 | RS08 | RS08 (KA sub-family) | RS08 (KA sub-family) | RS08 |
| Flash Memory | 4 KB | 8 KB | 12 KB | 4 KB | 8 KB | 4 KB |
| Maximum CPU Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Supply Voltage Range | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V | 2.7 V to 5.5 V |
| Peripheral Set | ADC, SCI/UART, I2C, Timers | ADC, SCI/UART, I2C, Timers (same) | ADC, SCI/UART, I2C, Timers (same) | ADC, SCI/UART, I2C, Timers (KA mix) | ADC, SCI/UART, I2C, Timers (KA mix) | ADC, SCI/UART, I2C, Timers (same) |
主要差異化特點
- Pin-compatible upward Flash migration path on the same 16-SOIC footprint (對比MC9RS08KB8CSG)
- Lowest unit cost in the RS08KB 16-SOIC lineup (對比MC9RS08KB8CSG)
- Wide 2.7V to 5.5V supply range allows single-rail 5V and 3.3V designs (對比MC9S08SH4MFK)
設計說明
Estimated: at VDD = 5.0V, active current at 20MHz is in the single-digit-mA range per the RS08KB family typical characteristics; in stop mode, current drops to a few microamps. Place a 100nF decoupling capacitor as close as possible to the VDD pin (pin 1) and a bulk 4.7uF to 10uF capacitor on the supply rail to suppress switching noise. The internal voltage regulator does not require an external bypass; respect the absolute maximum of 6V on VDD.
Keep the RESET line (PTB5) short and protect it with the recommended pull-up to VDD. Place the 16-SOIC on a 0.050-inch (1.27mm) pitch land pattern with the standard SOIC footprint; hand-soldering pads should be slightly enlarged to ease rework. Route ADC traces away from PWM or switching nodes, and add a ground pour under the MCU to reduce digital noise coupling into analog measurements.
Do not assume the RS08 background-debug pin is interchangeable across mask sets - always consult the latest datasheet before designing the debug header. When migrating code from HC08 to RS08, remember that the RS08 has a single global interrupt vector, so legacy vectored-interrupt source files need restructuring. The ADC reference defaults to VDD unless the internal reference is enabled in software; calibrate at production temperature for best absolute accuracy.
合規資訊
RoHS and REACH compliance inferred from NXP/Freescale product listing for the RS08KB family; halogen-free status not explicitly listed in the provided data and marked unknown.
