MC9RS08KA2CDB - 8-Bit RS08 MCU, 2KB Flash, 6-DFN | NXP
N.º de pieza: MC9RS08KA2CDB ✗ Fin de vida| Cant. | Precio unitario | Total |
|---|---|---|
| 1 | $3.2 | $3,20 |
| 10 | $2.85 | $28,50 |
| 100 | $2.4 | $240,00 |
| 500 | $2.05 | $1.025,00 |
| 1.000 | $1.75 | $1.750,00 |
MC9RS08KA2CDB Descripción general
Background: An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, program memory (Flash/ROM), data memory (RAM), and peripherals on one silicon die. The RS08 core is a streamlined variant of NXP's (formerly Freescale's) S08 architecture, designed for ultra-low-cost, ultra-low-pin-count applications where HCS08 performance is not required. The RS08 belongs to the 8-bit MCU product class within the broader microcontroller hierarchy (8-bit MCU -> microcontroller -> embedded computing -> semiconductor). It is intended for cost-sensitive, space-constrained designs that still need deterministic, low-power embedded control.
Key specifications: the MC9RS08KA2CDB operates from a 1.8 V to 5.5 V supply (typical operating points 2.5 V/3.3 V/5 V), includes 2KB (2K x 8) of Flash, 63 x 8 RAM, and 4 GPIO. The internal analog comparator (ACMP) listed on some distributor variants is the key analog peripheral in this family, enabling simple threshold detection without an external op-amp.
In design, the RS08 core uses a simplified S08 instruction set plus high-performance LDA, STA, and CLR instructions, allowing efficient C and assembly code generation on a tiny Flash budget. The 6-pin DFN-EP footprint with exposed pad gives a low thermal-resistance path and minimal PCB area, suited to coin-cell or battery-powered sensor nodes and appliance user-interface replacement.
Typical applications: low-end consumer appliances, replacement of discrete logic + analog timer ICs, AC/DC wall-cube controller interfaces, simple LED drivers, battery chargers, and remote controls. The combination of small package, integrated LVD/POR, and ACMP lets one chip replace multiple discrete components.
Design consideration: because only 4 I/O pins are available, designers must budget pin functions carefully — for example, one pin may be shared between ADC input, ACMP input, and external interrupt. Always connect the EP (exposed pad / pin 6 in some outlines) to the ground plane for thermal and electrical performance.
This page synthesizes datasheet specifications, current distributor pricing, drop-in same-family alternatives, and PCB-level design notes compiled from manufacturer documentation and aftermarket listings — material not consolidated in any single OEM source.
Alternativas directas para MC9RS08KA2CDB — mismo encapsulado, compatible pin a pin. Se excluyen las piezas de otro encapsulado que requieren retrabajo de la PCB.
Variantes de esta serie
Modelos de la misma serie compatibles directamente con MC9RS08KA2CDB (mismo factor de forma y huella) — difiere en Core Processor, Package, Program Memory Size, RAM Size, Mounting Type.
Herramienta de comparación rápida — seleccione piezas alternativas para compararlas lado a lado:
MC9RS08KA1CDBR
✅ Sustitución directa ⚠️ Especificaciones sin verificar✓ En stock
$0.5279 / unidad
Ver hoja de datos →MC9RS08KB4CWJ
✅ Sustitución directa✓ En stock
$1.49 / unidad
Ver hoja de datos →MC9RS08KB8CWJ574
✅ Sustitución directa✓ En stock
$0.74 / unidad
Ver hoja de datos →MC9RS08KA2CDB
✅ Sustitución directa✓ En stock
$1.75 / unidad
Ver hoja de datos →MC9RS08KA2CDB Valores máximos y características eléctricas
| Core Processor | RS08 |
| Core Size | 8-bit |
| Maximum CPU Frequency | 20 MHz (10 MHz bus, per DigiKey) |
| Program Memory Size | 2 KB (2K x 8) Flash |
| RAM Size | 63 x 8 (63 bytes) |
| EEPROM Size | None |
| Number of I/O Pins | 4 GPIO |
| Supply Voltage (Vcc/Vdd) | 1.8 V to 5.5 V |
| Encapsulado / Carcasa | 6-DFN-EP (3 x 3 mm) |
| Tipo de montaje | Surface Mount |
| Peripherals | LVD, POR, WDT, ACMP |
| Connectivity | None (no UART, SPI, or I2C on this device) |
| Instruction Set | Simplified S08 + LDA/STA/CLR extensions |
| Estado RoHS | Compliant (per distributor listing) |
Configuración de pines de MC9RS08KA2CDB
| Pin 1 | VDD — Power supply input |
| Pin 2 | VSS — Ground reference |
| Pin 3 | RESET — Reset input (active low) |
| Pin 4 | GPIO / ACMP — Multifunction GPIO with analog comparator input |
| Pin 5 | GPIO — General-purpose input/output |
| Pin 6 | EP — Exposed pad (must be soldered to ground plane for thermal dissipation) |
Aplicaciones típicas
MC9RS08KA2CDB es adecuado para 7 aplicacións: Low-End Appliance User-Interface Replacement, Battery-Powered Remote Control, Simple LED Driver / Blinker, AC/DC Wall-Cube Load Interface, Battery Charger State Controller, Sensor Threshold Detector, Automotive Aftermarket Replacement.
Low-End Appliance User-Interface Replacement
The MC9RS08KA2CDB replaces discrete logic and mechanical timers in low-cost white goods with a single 6-pin IC. Its integrated ACMP can read a potentiometer or thermistor divider and drive an LED or relay via one GPIO. Operating from 1.8 V to 5.5 V allows direct connection to AC/DC wall-cube outputs or battery packs. The 6-DFN-EP footprint drops onto boards designed for the part's pinout, and 2 KB of Flash holds a simple state-machine plus UI lookup tables without external memory. Compared to a 555-timer + discrete flip-flop implementation, the KA2CDB shrinks the BOM, removes trim pots, and adds software-driven timing, which speeds variant changes on the production line.
Recomendado
Battery-Powered Remote Control
In handheld IR / RF remote controls, the MC9RS08KA2CDB runs from a coin cell or 2 x AAA cells across the 1.8 V to 5.5 V supply range and consumes only what the integrated peripherals demand. The internal ACMP can wake the part on a button-press event, with the WDT handling button-scan timing. The 6-pin DFN-EP fits behind a key cap on a single-sided PCB, freeing layout space for the battery clip. With 63 bytes of RAM and 2 KB Flash, designers can implement debounce, repeat codes, and sleep routines easily. The RS08 core's deterministic interrupt latency makes it ideal for tight button-to-IR protocols that must meet consumer-electronics timing tolerances.
Recomendado
Simple LED Driver / Blinker
The MC9RS08KA2CDB drives multi-mode LED blinkers, safety strobes, or fairy-light controllers using GPIO bit-banging and the ACMP for simple battery-voltage sensing. Two GPIO can be reserved for LEDs (one for status, one for the load) while the remaining two drive the ACMP inputs and a user push-button. Power comes straight from the LED battery, with the on-chip LVD cutting output when the cell drops below threshold to prevent deep discharge. The wide 1.8 V to 5.5 V supply lets the same code run on 1S Li-ion, 2 x AA, or 3 V coin cells. The 6-DFN-EP package is small enough to fit a standard CR2032 holder envelope and the device's ultra-low-power profile extends battery life.
Recomendado
AC/DC Wall-Cube Load Interface
On the secondary side of an isolated AC/DC wall cube, the MC9RS08KA2CDB provides a smart interface between the low-voltage rail and the device being powered (a handset, IoT node, or appliance). Its 5 V-tolerant inputs connect directly to the rectified secondary, and the integrated LVD signals plug-presence to the host. One GPIO can be assigned to USB-DM-style signaling or to a simple opto-isolated feedback path. The EP-pad DFN package handles the small thermal load of the always-listening logic. Designers appreciate the part's small BOM footprint versus a discrete solution and the regulatory simplicity of using an MCU that fits within an isolation barrier.
Recomendado
Battery Charger State Controller
A MC9RS08KA2CDB can supervise a simple linear or switch-mode charger for single-cell Li-ion / LiFePO4 packs, using the ACMP to compare battery voltage against an internal bandgap reference and a GPIO to drive a power-FET gate. The on-chip POR guarantees a defined state at first plug-in, and the LVD disables charging below a safe minimum. The 2 KB Flash holds the CC/CV profile lookup tables and indicator-LED logic without external EEPROM. Operating from 1.8 V to 5.5 V covers the entire Li-ion charge-discharge window, while the 6-pin DFN-EP fits inside a USB-C charger housing. Designers should follow NXP's EMC guidelines in the RS08KA datasheet when driving high-current switching FETs from the same board.
Recomendado
Sensor Threshold Detector
In a sensor-threshold detector, the MC9RS08KA2CDB uses its analog comparator (ACMP) to compare an external sensor (thermistor, photocell, or hall sensor) against a fixed reference. The 8-bit RS08 core then drives an alert GPIO and a status LED without an external op-amp or window comparator. The integrated WDT protects against sensor-lockup, while LVD/POR handle brown-out events on long wire runs. With only 4 GPIO, the device is suited to one-sensor-one-output designs, but multiple KA2CDBs can be chained on a single RS-485-like link. The 6-DFN-EP 3x3 mm footprint allows placement inside small enclosures, and the wide supply tolerance simplifies field wiring across 3.3 V to 5 V systems.
Recomendado
Automotive Aftermarket Replacement
The MC9RS08KA2CDB is not AEC-Q100 qualified, so automotive designs must use it only in non-safety, aftermarket retrofit roles where the operating environment is benign. The 6-pin DFN-EP part works well inside a sealed plastic enclosure for climate-control trim, seat-position memory, or interior lighting. Its 1.8 V to 5.5 V supply range matches typical 5 V regulated body-electronics rails, and the integrated LVD/POR guard against transient automotive supply dips. With 2 KB Flash and 63 bytes RAM, the device is overkill for many trim functions but unbeatable for BOM cost. Production automotive designs should move to an AEC-Q100 Kinetis E or S12Z part on the same PCB footprint only after a full qualification program.
Recomendado
Resumen de productos recomendados
Datos de referencia de ingeniería para MC9RS08KA2CDB — comparación, orientación de diseño e información de cumplimiento.
Guía de selección
Comparación con alternativas
| Parámetro | Este producto | MC9RS08KA1CDBR | MC9RS08KB4CWJ | MC9RS08KB8CWJ574 |
|---|---|---|---|---|
| Package | 6-DFN-EP (3x3 mm) | 6-DFN-EP (3x3 mm) - same | 6-DFN-EP (3x3 mm) - same | 6-DFN-EP (3x3 mm) - same |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Core | RS08 8-bit | RS08 8-bit | RS08 8-bit | RS08 8-bit |
| Program Memory | 2 KB Flash | 1 KB Flash | 4 KB Flash | 8 KB Flash |
| CPU Speed | 20 MHz (10 MHz bus per DigiKey) | 20 MHz | 20 MHz | 20 MHz |
| Supply Voltage | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V |
| Peripherals | LVD, POR, WDT, ACMP | LVD, POR, WDT, ACMP | LVD, POR, WDT, ACMP | LVD, POR, WDT, ACMP |
Diferenciadores clave
- Smallest Flash configuration in RS08KA family (frente a MC9RS08KB4CWJ)
- Same RS08 core across alternatives (frente a MC9RS08KA1CDBR)
- Limited GPIO budget (4 GPIOs only) (frente a MC9S08AW16AE0CLDR)
Notas de diseño
Place a 100 nF X7R decoupling capacitor within 2 mm of the VDD pin (pad 1) and a 10 uF bulk capacitor on the same supply rail, since the 6-DFN-EP package has very short internal bond wires that respond to high-frequency supply transients. The integrated LVD triggers a clean reset when VDD drops below the configured threshold, which protects flash integrity in brown-out events typical of AC/DC wall-cube designs.
Solder the exposed pad (EP, pin 6) to a continuous ground pour on at least 1 oz copper. Without this, theta_JA rises dramatically on the small 3 mm x 3 mm outline, and any sustained GPIO drive current derates quickly. If the application drives a relay or LED string from a GPIO, distribute the load across multiple GPIOs and add a small SOT-23 FET for high-current loads.
Because the device exposes only 4 GPIO plus VDD/VSS/RESET/EP, plan pin functions carefully during schematic capture. A common pattern is: GPIO1 = ACMP input, GPIO2 = button wake-up, GPIO3 = LED indicator, GPIO4 = communications bit-bang or analog output. Keep high-speed signals away from the EP pad ground return path on layer 2 to maintain signal integrity.
Do not assume this part is a 6-pin equivalent of an S08/HCS08 device; the RS08 ISA is a strict subset, and several S08 peripherals (KBI, SCI, ADC) are absent on KA2. After assembly, verify the on-chip oscillator tolerance at the application's voltage and temperature — internal oscillators in this family typically have +/- 2 % to +/- 5 % drift, which is fine for debounce but inadequate for UART timing.
Información de cumplimiento
RoHS compliance per distributor product pages; halogen-free and REACH status not explicitly confirmed in the verified data. AEC-Q100 is not qualified - this device is for non-automotive / aftermarket use only.
