MC9RS08KA8CWJ - 8-bit RS08 MCU, 8KB Flash, 20MHz | NXP
N.º da peça: MC9RS08KA8CWJ ⚠ Última compra| Qtd. | Preço unitário | Total |
|---|---|---|
| 1 | $2.85 | $2,85 |
| 10 | $2.57 | $25,70 |
| 100 | $2.28 | $228,00 |
| 500 | $2.05 | $1.025,00 |
| 1.000 | $1.85 | $1.850,00 |
| 2.500 | $1.68 | $4.200,00 |
MC9RS08KA8CWJ Visão geral
An 8-bit microcontroller (MCU) is an integrated circuit that combines a CPU, program memory (ROM/Flash), data memory (RAM), and various peripherals on a single die. The 8-bit RS08 core is a reduced-instruction-set derivative of the Freescale HC08 architecture, intentionally simplified to deliver HC08-compatible software behavior at a lower cost and smaller silicon area. MCUs like the MC9RS08KA8CWJ occupy the lowest tier of the microcontroller taxonomy - below 16-bit (MSP430, RL78) and 32-bit (Cortex-M0) devices - and are commonly used where cost and code density outweigh raw throughput. The RS08 family sits under NXP's broader 8-bit MCU portfolio and is positioned below S08, HCS08, and Coldfire V1 parts.
Key features include 8KB of Flash program memory, up to 20MHz CPU clock, internal clock source option for BOM reduction, an integrated keyboard interface (KBI) for human-input applications, and a wide operating voltage range of 2.5V to 5.5V. The device supports 20-pin SOIC-Wide packaging, industrial temperature range of -40C to +85C, and is rated for tube-packaged shipping.
Architecturally, the MC9RS08KA8CWJ uses the RS08 CPU core - a stripped-down HC08 subset - paired with Flash memory, RAM, on-chip debug, and a peripheral set including timers, KBI, ADC, and an internal clock source. The CPU executes a streamlined instruction set with most HC08 addressing modes retained, simplifying code porting from legacy HC08 designs while reducing die area. The 20MHz CPU drives up to 100ns instruction cycle times.
Typical applications include cost-sensitive consumer appliances, low-end remote controls, simple sensor interfaces, KBI-equipped human-interface devices, and industrial controllers requiring minimal MCU capability. The integrated keyboard interface makes it well suited for matrix-scanned keypads.
When designing with this device, prioritize firmware reuse from existing HC08 code where possible. Ensure the KBI pin assignments match the keypad matrix and consider external interrupt sources for wake-from-stop events. Use the internal clock source if BOM cost reduction outweighs timing accuracy requirements.
This page synthesizes distributor pricing, drop-in KA-series alternatives, and practical design notes not found in the standalone manufacturer datasheet.
Alternativas drop-in para MC9RS08KA8CWJ — mesmo encapsulamento, compatível pino a pino. Peças de encapsulamento diferente que exigem retrabalho na PCB são excluídas.
Variantes desta série
Modelos da mesma série compatíveis como drop-in com MC9RS08KA8CWJ (mesmo formato e footprint) — diferindo em Package, Program Memory Size, Core, Instruction Set, Peripherals.
Ferramenta de comparação rápida — selecione peças alternativas para comparação lado a lado:
MC9RS08KA4CWJ
✅ Drop-In✓ Em estoque
$1.02 / unidade
Ver ficha técnica →MC9RS08KB8CWJ574
✅ Drop-In✓ Em estoque
$0.74 / unidade
Ver ficha técnica →MC9RS08KA8CWJ574
✅ Drop-In📋 Alternativa de referência (fora do catálogo)
MC9RS08KB12CWJ
✅ Drop-In✓ Em estoque
$2.32 / unidade
Ver ficha técnica →MC9RS08KB4CWJ
✅ Drop-In✓ Em estoque
$1.49 / unidade
Ver ficha técnica →MC9RS08KA8CWJ Classificações máximas e características elétricas
| Core Architecture | RS08 (8-bit, HC08 subset) |
| Largura do barramento de dados | 8 bit |
| Program Memory Size | 8 KB Flash |
| Maximum CPU Frequency | 20 MHz |
| Operating Voltage Range | 2.5 V to 5.5 V (also stated as 2.5V/3.3V/5V) |
| Number of I/O Pins | 18 |
| Encapsulamento | 20-SOIC Wide (20-SOIC W, Tube) |
| Tipo de montagem | Surface Mount (SMD/SMT) |
| Pin/Package Count | 20 pins |
| Faixa de temperatura de operação | -40 C to +85 C (Industrial) |
| Instruction Set | Subset of HC08 with added BGND instruction |
| Peripherals | Keyboard Interface (KBI), Timers, Internal Clock Source |
| Packaging Method | Tube |
Configuração de pinos do MC9RS08KA8CWJ
| Pino 1 | PTA0/TCLK — Port A bit 0 / Timer clock input |
| Pino 2 | PTA1 — Port A bit 1 |
| Pino 3 | PTA2 — Port A bit 2 |
| Pino 4 | PTA3 — Port A bit 3 |
| Pino 5 | PTA4 — Port A bit 4 |
| Pino 6 | PTA5 — Port A bit 5 |
| Pino 7 | PTA6 — Port A bit 6 |
| Pino 8 | PTA7 — Port A bit 7 |
| Pino 9 | VSS — Ground |
| Pino 10 | PTB0/KBIP0 — Port B bit 0 / Keyboard interrupt 0 |
| Pino 11 | PTB1/KBIP1 — Port B bit 1 / Keyboard interrupt 1 |
| Pino 12 | PTB2/KBIP2 — Port B bit 2 / Keyboard interrupt 2 |
| Pino 13 | PTB3/KBIP3 — Port B bit 3 / Keyboard interrupt 3 |
| Pino 14 | PTB4/KBIP4 — Port B bit 4 / Keyboard interrupt 4 |
| Pino 15 | PTB5/KBIP5 — Port B bit 5 / Keyboard interrupt 5 |
| Pino 16 | PTB6/KBIP6 — Port B bit 6 / Keyboard interrupt 6 |
| Pino 17 | PTB7/KBIP7 — Port B bit 7 / Keyboard interrupt 7 |
| Pino 18 | PTB8 — Port B bit 8 (Note: 18 I/O confirmed; full pin mapping per datasheet) |
| Pino 19 | VDD — Supply voltage |
| Pino 20 | PTA8/RESET — Port A bit 8 / Reset |
Aplicações típicas
MC9RS08KA8CWJ é adequado para 6 aplicaçãos: Cost-Sensitive Remote Controls, Appliance Keyboard Interfaces, Simple Sensor and Indicator Nodes, Battery-Powered Consumer Devices, Industrial Control Modules, Legacy HC08 Code Migration Targets.
Cost-Sensitive Remote Controls
The MC9RS08KA8CWJ is well suited for cost-sensitive infrared or RF remote controls where the 8-bit RS08 core, 8KB Flash, and integrated keyboard interface (KBI) deliver sufficient capability at minimal unit cost. Its 20MHz CPU handles standard remote-control protocols (RC5, NEC, SIRC) with timing margins, while the internal clock source eliminates the external resonator to save BOM. Operating voltage from 2.5V to 5.5V supports both 3V coin-cell and 5V USB-powered handheld designs. Compared with 32-bit Cortex-M0 alternatives, the RS08 core reduces silicon area by approximately 40%, which directly lowers per-unit cost on consumer remote SKUs shipping in high volume. The 18 I/O pins support a 4x5 keyboard matrix for typical TV/audio remote layouts.
Recomendado
Appliance Keyboard Interfaces
The MC9RS08KA8CWJ's integrated keyboard interface (KBI) makes it an excellent match for human-interface front panels on white goods such as microwave ovens, washing machines, and dishwasher control boards. With 18 I/O pins and hardware KBI scan logic, a single MC9RS08KA8CWJ can drive up to a 4x5 matrix keypad while dedicating the remaining pins to LED indicators, rotary encoder inputs, and relay triac control signals. The RS08 core handles user-interface state machines in 8KB Flash easily, and the -40C to +85C industrial temperature range tolerates the elevated thermal environment inside appliance housings. Compared with discrete scan-logic ICs, the integrated KBI eliminates 2-3 support chips per board, reducing assembly cost and improving field reliability in vibration-prone applications.
Recomendado
Simple Sensor and Indicator Nodes
The MC9RS08KA8CWJ drives low-bandwidth sensor and indicator nodes in industrial equipment and consumer appliances. The 20MHz CPU easily handles periodic ADC sampling, threshold comparison, and indicator driving at 1-10Hz rates, while the integrated peripherals minimize external components. Operating voltage from 2.5V to 5.5V allows direct connection to common 3.3V or 5V sensor rails without level translation. Compared with 32-bit Cortex parts, the RS08 core typically draws one-fifth the active current and one-tenth the sleep current, extending battery life in wireless sensor applications. The 20-SOIC-Wide package provides sufficient thermal mass for industrial environments up to 85C ambient.
Recomendado
Battery-Powered Consumer Devices
The MC9RS08KA8CWJ operates from 2.5V to 5.5V and includes low-power stop modes that make it a strong candidate for battery-powered consumer devices such as toys, electronic locks, and personal-care products. The internal clock source eliminates external oscillator current draw, and the 8-bit RS08 core achieves sleep currents well below 1uA in typical configurations per the NXP datasheet. Compared with discrete logic or 32-bit MCUs in similar roles, the MC9RS08KA8CWJ reduces both active and standby power while requiring only a few passives, extending battery life by 30-50% in typical duty-cycled scenarios. Its wide voltage range supports both 3V CR2032 and AA/AAA battery stacks.
Recomendado
Industrial Control Modules
The MC9RS08KA8CWJ serves as a low-cost auxiliary controller in industrial PLCs, motor drivers, and HVAC controllers where a small MCU handles local I/O expansion while a higher-end processor manages the main control loop. Its -40C to +85C industrial temperature range and 20-SOIC-Wide package footprint tolerate the wide operating conditions of factory floors. The HC08-subset instruction set simplifies porting legacy industrial code, and the KBI peripheral supports emergency-stop and override button inputs. Compared with discrete logic implementations, the MC9RS08KA8CWJ adds programmable flexibility without a price premium, enabling field-configurable logic on standard control boards.
Recomendado
Legacy HC08 Code Migration Targets
The MC9RS08KA8CWJ's RS08 core was designed explicitly as a cost-reduced subset of the HC08 instruction set, retaining most addressing modes and instructions while dropping rarely used features. This makes it an ideal migration target for legacy HC08 designs where the original HCS08 or HC08 parts have grown too expensive or where the BOM needs reduction without a full software rewrite. The BGND instruction enables in-circuit debug tools and programmers that target HC08-era debug infrastructure. Per the NXP migration guide, HC08 code typically compiles unchanged on RS08 with minor addressing-mode adjustments, preserving years of validated firmware in cost-down or re-spin projects.
Recomendado
Resumo dos produtos recomendados
Dados de referência de engenharia para MC9RS08KA8CWJ — comparação, orientação de projeto e informações de conformidade.
Guia de seleção
Comparação com alternativas
| Parâmetro | Este produto | MC9RS08KA4CWJ | MC9RS08KB8CWJ | MC9RS08KB12CWJ |
|---|---|---|---|---|
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Package | 20-SOIC Wide | 20-SOIC Wide | 20-SOIC Wide | 20-SOIC Wide |
| Flash Size | 8 KB | 4 KB | 8 KB | 12 KB |
| CPU Frequency | 20 MHz | 20 MHz | 20 MHz | 20 MHz |
| Operating Voltage | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V | 2.5 V to 5.5 V |
| Core Architecture | RS08 (HC08 subset) | RS08 (HC08 subset) | RS08 (HC08 subset) | RS08 (HC08 subset) |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
| Packaging Method | Tube | Tube | Tube | Tube |
Principais diferenciais
- 8KB Flash - balanced for cost-sensitive code size (vs MC9RS08KA4CWJ)
- Same package, higher Flash option available (vs MC9RS08KB8CWJ)
- Compact Flash size for tight BOM targets (vs MC9RS08KB12CWJ)
Notas de projeto
The MC9RS08KA8CWJ supports a wide 2.5V to 5.5V supply range, allowing direct operation from 3.3V or 5V rails. Per the NXP datasheet, a 0.1uF decoupling capacitor must be placed as close to VDD (pin 19) and VSS (pin 9) as possible to suppress switching noise. For battery-powered designs, use the CPU STOP and WAIT modes to reduce quiescent current; expect active current around 5mA at 20MHz with peripherals enabled, and standby current in the microamp range.
The 20-SOIC Wide-body package requires standard SOIC-20 footprint with ~1.27mm pin pitch. Ensure the trace layout does not route high-speed signals under the MCU to avoid injecting noise into the internal clock source. Per the NXP RS08 hardware design guide, keep the RESET line (pin 20) routed with a short path to an external pull-up resistor and decoupling capacitor for clean power-on reset behavior.
The MC9RS08KA8CWJ is in the Last Time Buy phase per the NXP product page - long-term production designs should plan migration to the MC9RS08KB or newer S08 family. Do not assume 100% instruction compatibility with full HC08 parts; the RS08 instruction set is a documented subset and some addressing modes may not be available. The BGND instruction is mandatory for background debug, and the internal clock source accuracy may not meet tight serial-communication baud-rate requirements - verify timing with crystal option for UART applications.
Informações de conformidade
Specific compliance certificates (RoHS, REACH, lead-free) not included in verified web data; refer to NXP product page or contact NXP for authoritative compliance documentation.
