MC9RS08KA1CSC - 8-Bit RS08 MCU, 1KB Flash, SOIC-8 | NXP
MPN: MC9RS08KA1CSC ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.27 | $2.27 |
| 10 | $2.27 | $22.70 |
| 100 | $2.27 | $227.00 |
| 500 | $2.27 | $1,135.00 |
| 1,000 | $2.27 | $2,270.00 |
MC9RS08KA1CSC Overview
The RS08 core is a compact CISC processor built around the S08 instruction set with additional high-performance LDA, STA, and CLR instructions. This MCU is intended for simple control, sensing, and actuator tasks where a larger 8-bit MCU would add unnecessary cost, memory, and board area. Its 63-byte RAM and 1 KB flash are sufficient for startup code, basic state machines, and tightly bounded control logic rather than general-purpose applications.
The device operates from a low-voltage supply suitable for embedded and battery-oriented designs, with an internal oscillator eliminating a mandatory external clock source. The RS08KA family also includes timer and interrupt resources for periodic sensing and event handling. Power-management features and the small package help reduce both board footprint and system complexity in cost-driven products.
Typical uses include simple keypad or button interfaces, low-speed motor and relay controllers, basic sensor nodes, household appliance controls, and auxiliary embedded functions. The compact SOIC-8 outline is useful when through-hole or leaded assembly is preferred, but its 1 KB program memory is a strict constraint for larger control algorithms.
When designing around MC9RS08KA1CSC, verify the exact pin multiplexing, reset behavior, oscillator limits, and supply-voltage range in the NXP datasheet. Avoid assuming that all RS08 family members are software-compatible, because memory size and peripheral configurations can differ. A migration to a larger MCU may be required if the application grows beyond the 63-byte RAM and 1 KB flash budget.
This product page combines verified distributor data, lifecycle information, package details, design constraints, and an honest assessment of alternative availability. It is intended to help engineers quickly determine whether this RS08KA device fits a minimal embedded-control design before requesting documentation and sourcing support.
Drop-in alternatives for MC9RS08KA1CSC — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with MC9RS08KA1CSC (same form factor and footprint) — differing in Package, Maximum Clock Frequency, Mounting Type, Core Processor, Data Bus Width.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC9RS08KA1CDB
✅ Drop-In✓ In Stock
$2.05 / Unit
View Datasheet →MC9RS08KA2CSC
✅ Drop-In📋 Reference alternative (not in catalog)
MC9RS08KA2CSCR
✅ Drop-In📋 Reference alternative (not in catalog)
MC9RS08KA1CSC Maximum Ratings & Electrical Characteristics
| Product Type | 8-bit microcontroller (MCU) |
| Processor Core | RS08 |
| Processor Series | RS08KA |
| Data Bus Width | 8-bit |
| Maximum Clock Frequency | 10 MHz |
| Flash Memory | 1 KB (1K x 8) |
| Internal RAM | 63 bytes |
| Supply Voltage Range | 1.8 V to 5.5 V |
| Architecture | CISC |
| Internal Oscillator | Yes |
| System Protection | LVD, POR, WDT |
| Package | 8-pin SOIC |
| Mounting Type | Surface Mount |
| Operating Voltage | 2.5 V / 3.3 V / 5 V |
| Programming Memory | 1 KB internal flash |
| Timer | 8-bit modulo timer |
| Keyboard Interrupts | Five keyboard interrupt resources |
| RoHS Status | Unknown; not stated in verified data |
| Manufacturer | NXP Semiconductors |
MC9RS08KA1CSC 8-pin soic Pin Configuration Guide
Pin configuration for MC9RS08KA1CSC (8-pin soic package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for MC9RS08KA1CSC.
Refer to the datasheet for full pin configuration.
Typical Applications
MC9RS08KA1CSC is suitable for 7 applications: Cost-Sensitive Basic Control, Simple Sensor Node, Button and Keypad Interface, Simple Relay and Actuator Controller, Battery-Powered Household Device, Low-Speed Motor or Relay Timing, Compact Auxiliary Embedded Function.
Cost-Sensitive Basic Control
MC9RS08KA1CSC fits simple appliance controls, button interfaces, and small state-machine products where a 1 KB flash budget is sufficient. The RS08 8-bit CISC core and 63 bytes of RAM can handle sequencing, basic logic, and low-rate input polling without a larger MCU. The 8-pin SOIC package keeps the board compact, while the internal oscillator removes a mandatory external clock component. Designers should constrain firmware size and verify the exact pin functions in the NXP datasheet before finalizing the control PCB.
Recommended
Simple Sensor Node
The MC9RS08KA1CSC can supervise basic analog or digital sensing functions in a compact embedded node. Its 1.8 V to 5.5 V feature range and internal oscillator make it useful in low-power, low-complexity systems, provided the exact operating limits are confirmed. The small memory footprint favors short acquisition and decision code rather than buffering or complex algorithms. Use the 63-byte RAM carefully, and avoid designs that require substantial protocol stacks or high-resolution data storage.
Recommended
Button and Keypad Interface
MC9RS08KA1CSC is appropriate for small keypad, debounced switch, and menu-control subsystems. The family description identifies five keyboard interrupt resources, allowing the MCU to respond to external events while executing a compact control loop. This is useful in products where the keypad is the primary human interface and the required firmware remains below the 1 KB flash limit. Validate debounce timing, interrupt behavior, and active levels against the exact datasheet rather than assuming compatibility with larger RS08 devices.
Recommended
Simple Relay and Actuator Controller
The compact RS08KA MCU can control relays, indicators, or other low-rate actuators in compact embedded products. Its 8-bit architecture and timer resources are sufficient for basic sequencing and debounce logic, while the 8-pin SOIC package simplifies leaded assembly. The device is not a replacement for a high-current driver; external transistors, protection, and appropriate power components remain necessary. Confirm pin drive capability, supply behavior, and watchdog requirements in the manufacturer documentation.
Recommended
Battery-Powered Household Device
MC9RS08KA1CSC can serve as the control core in a small battery-powered household device where the application is primarily event-driven. The internal oscillator and low-resource architecture reduce component count, while the compact SOIC-8 package supports space-constrained boards. Actual battery life depends on the complete firmware, peripherals, pull states, and sleep behavior, none of which are fully quantified in the supplied data. Validate low-power modes and current consumption against the NXP datasheet and application requirements.
Recommended
Low-Speed Motor or Relay Timing
The MC9RS08KA1CSC is suitable for simple timing and open-loop control tasks where the system does not require high computation or precision motor algorithms. The RS08 core can manage scheduled outputs and basic feedback logic within its limited memory budget. External driver circuitry is required for most motors, and protection against inductive transients must be designed separately. Confirm timer resolution, maximum clock conditions, and pin electrical limits before relying on timing-critical behavior.
Recommended
Compact Auxiliary Embedded Function
MC9RS08KA1CSC can add a small local control function to a larger appliance or module without committing to a high-memory microcontroller. This is useful for status LEDs, limit detection, simple interlocks, or local button logic while another processor handles system-wide tasks. The 63-byte RAM and 1 KB flash make partitioning the firmware essential. Define communication boundaries carefully because the supplied data does not specify a rich communications peripheral set for this exact variant.
Recommended
Recommended Products Summary
Engineering reference data for MC9RS08KA1CSC — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC9RS08KA1CDB | MC9RS08KA2CSC | MC9RS08KA2CSCR |
|---|---|---|---|---|
| Package | 8-pin SOIC | SOIC-8 | SOIC-8 | SOIC-8 |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Processor Core | RS08 | RS08 | RS08 | RS08 |
| Data Bus Width | 8-bit | 8-bit | 8-bit | 8-bit |
Key Differentiators
- Extremely compact memory footprint (vs MC9RS08KA2CSC)
- Targeted ultra-low-cost positioning (vs MC908GP32CFBE)
- Internal oscillator integration (vs MC9RS08KA2CSCR)
Design Notes
Before power-up, confirm the exact supply range, operating voltage modes, absolute maximum ratings, and power-on reset behavior in the NXP datasheet. The supplied distributor data references 1.8 V to 5.5 V and also 2.5 V, 3.3 V, and 5 V, so do not select decoupling or regulator values from the broadest listing alone. Keep the supply decoupling path short and validate brownout behavior for the final external load.
Use the manufacturer package drawing and verified pin table to finalize the SOIC-8 land pattern. Place the decoupling capacitor close to the device power pin and preserve a clean ground return. Because the verified data does not provide the complete MC9RS08KA1CSC pin table, do not infer programming, reset, oscillator, or I/O functions from a related RS08 part without schematic review.
The 1 KB flash and 63-byte RAM are the dominant design constraints. Measure the linked code size early, avoid library-heavy middleware, and keep stack depth conservative. The related MC9RS08KA2CSC has 2 KB flash, so treating it as a direct replacement without checking the memory and pin behavior can create software or hardware surprises.
For simple switching or keypad applications, separate sensitive timing paths from high-current switching loops and keep external driver traces away from the MCU supply and signal pins. If relays or motors are used, provide protection networks and adequate return-current paths; the MCU should control drivers through defined interfaces rather than carry inductive current directly.
Compliance Information
The supplied web data does not explicitly state RoHS, REACH, lead-free, halogen-free, or conflict-minerals status. AEC-Q100 is not indicated for this general-purpose MCU.