NXP Semiconductors MC9RS08KA8CWGR

Overview

MC9RS08KA8CWGR from NXP Semiconductors (formerly Freescale) is an 8-bit RS08 core microcontroller with 8 KB flash, 254-byte RAM, and integrated peripherals including 10-bit ADC, TPM timer, I²C, dual 8-bit timers, analog comparator, and keyboard interrupt module. It operates from 1.8 V to 5.5 V across –40°C to 85°C and supports low-power stop/wait modes with wake-up via RTI, KBI, or ACMP - used in battery-powered sensor nodes and industrial control panels.

For engineers reviewing the MC9RS08KA8CWGR datasheet, MC9RS08KA8CWGR pinout, MC9RS08KA8CWGR application, or MC9RS08KA8CWGR equivalent, this page delivers verified technical context, package-specific pin mapping, real-world use cases, and validated alternative options for cost-sensitive, low-voltage embedded designs requiring debug support and mixed-signal integration.

Technical Context

The MC9RS08KA8CWGR implements a subset of the HC08 instruction set augmented with BGND for single-wire background debug, and uses a frequency-locked-loop (FLL)-based internal clock source (ICS) delivering up to 10 MHz bus frequency with ±2% deviation over voltage and temperature. Its oscillator supports both crystal/ceramic resonator (31.25 kHz–5 MHz) and external clock inputs.

System-level protection includes COP watchdog reset (with dedicated 1 kHz clock option), low-voltage detection (LVD) with interrupt/reset, illegal opcode/address detection, and flash block protection. Peripherals are designed for operation in stop mode: ADC (12-channel, 10-bit, 2.5 μs conversion), ACMP (rail-to-rail, internal bandgap reference), and TPM (2-channel PWM/capture/compare).

Key Specifications

Pinout & Package

MC9RS08KA8CWGR is supplied in a 16-pin SOIC package (Case 751G), with 14 GPIOs (including one output-only and one input-only pin), configurable pull-ups/pull-downs, hysteresis on all inputs, and slew-rate/drive-strength control on outputs.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar 8-bit microcontroller applications.

Compared with MC9RS08KA8CWGR, MC9RS08KA4CWGR offers identical low-power behavior and debug capability at reduced memory cost, while S9KEAZ128AMLH delivers scalable performance but mandates layout revision and toolchain migration.

Availability

MC9RS08KA8CWGR is available at Aetrix Electronics and suitable for industrial sensor nodes, smart thermostat interfaces, LED lighting dimmers, and DC motor speed controllers requiring stable component supply and long-term manufacturability.

Supply support for MC9RS08KA8CWGR includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

NXP Semiconductors is a global semiconductor leader focused on secure connectivity solutions for automotive, industrial, and IoT applications, with deep heritage in microcontrollers dating to its Freescale acquisition.

The RS08 family - including MC9RS08KA8CWGR - was engineered for ultra-low-cost, ultra-low-power embedded control in space-constrained, battery-operated devices where debug accessibility and analog integration are critical.

FAQ

What is the maximum bus frequency supported by the MC9RS08KA8CWGR?

The MC9RS08KA8CWGR supports a maximum bus frequency of 10 MHz, achieved via its FLL-controlled internal clock source (ICS) operating from a trimmed internal reference. This frequency is guaranteed across the full operating voltage range (1.8 V to 5.5 V) and temperature range (–40°C to 85°C), enabling deterministic real-time execution in timing-critical control tasks. The MC9RS08KA8CWGR does not require an external crystal to reach this speed.

Does the MC9RS08KA8CWGR support in-circuit debugging without additional hardware?

Yes, the MC9RS08KA8CWGR features a single-wire background debug (BKGD) interface on PTA4, allowing full in-circuit debugging, breakpoint setting, and flash programming using only a standard UART-to-BKGD adapter. No JTAG emulator or dedicated debug header is needed, reducing development cost and board space. The MC9RS08KA8CWGR also supports a single hardware breakpoint during active debugging sessions.

Can the MC9RS08KA8CWGR operate in stop mode while retaining ADC functionality?

Yes, the MC9RS08KA8CWGR's 10-bit ADC remains fully operational in stop mode, supporting up to 8 channels in the 16-pin package. Conversion time is 2.5 μs, and the module can be triggered by internal timers or external events. When combined with the 1.5 μA typical stop current at 1.8 V, this enables energy-efficient periodic sensor sampling - a key capability confirmed in the MC9RS08KA8CWGR datasheet Section 3.7 and peripheral description.

What are the valid crystal frequency ranges for the MC9RS08KA8CWGR's external oscillator (XOSC)?

The MC9RS08KA8CWGR XOSC supports two crystal/resonator ranges: low-band (31.25 kHz to 39.0625 kHz) and high-band (1 MHz to 5 MHz). These ranges are selected via the RANGE bit in the OSCSC register. The MC9RS08KA8CWGR does not support crystals above 5 MHz in XOSC mode; higher frequencies require external clock injection into EXTAL. Startup times vary from 5 ms to 400 ms depending on gain and range configuration.

How many keyboard interrupt (KBI) pins does the MC9RS08KA8CWGR provide in its 16-pin SOIC package?

The MC9RS08KA8CWGR in the 16-pin SOIC package provides four keyboard interrupt pins: PTB0 through PTB3 (KBIP4–KBIP7). These pins support rising/falling edge detection and can wake the device from stop mode. While the full KA8 series supports eight KBI inputs in 20-pin packages, the 16-pin variant (including MC9RS08KA8CWGR) maps KBI to the lower four Port B pins - a confirmed allocation per Pin Assignment Table 1 and Figure 3 in the official datasheet.