NXP Semiconductors MC9RS08KB4CSG

Overview

MC9RS08KB4CSG from NXP Semiconductors (formerly Freescale) is an 8-bit RS08 core microcontroller in a 16-pin SOIC NB package, featuring 4 KB flash, 126-byte RAM, 10-bit ADC with 12 channels, and integrated peripherals including I²C, SCI, TPM, ACMP, and RTI. It operates from 1.8 V to 5.5 V across –40 °C to 85 °C and supports low-power stop/wait modes - used in battery-powered sensor nodes and industrial control interfaces.

For engineers reviewing the MC9RS08KB4CSG datasheet, MC9RS08KB4CSG pinout, MC9RS08KB4CSG application, or MC9RS08KB4CSG equivalent, key selection criteria include its 4 KB flash size, 126-byte RAM allocation, 24-pin QFN/16-pin SOIC NB package options, 10 MHz max bus frequency via internal clock source, and support for single-wire background debug interface.

Technical Context

The MC9RS08KB4CSG implements an RS08 CPU core - a subset of the HC08 instruction set with BGND support and a single global interrupt vector. Its internal clock source (ICS) uses a frequency-locked loop (FLL) with precision trimming enabling ±2% deviation over voltage and temperature, delivering up to 10 MHz bus frequency.

System-level protection includes COP reset with dedicated 1 kHz low-power oscillator, low-voltage detection (LVD) with reset/interrupt, illegal opcode/address detection, and flash-block protection. Wakeup from stop mode is supported by RTI, KBI, ADC, ACMP, SCI, and LVD events.

Key Specifications

Pinout & Package

MC9RS08KB4CSG is packaged in a 16-pin SOIC NB (Case 751B), 3.9 mm × 4.9 mm body, 1.27 mm pitch, with exposed pad not present. Pin assignments are defined per Table 1 and Figure 4 of the Rev. 5 datasheet.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC9RS08KB4CSG, MC9RS08KB8CSG offers double flash and RAM in identical footprint for seamless upgrade, while S08AW60CFGE adds CAN and scalability at the cost of larger package and higher BOM cost - making MC9RS08KB4CSG optimal for cost-sensitive, low-complexity embedded control.

Availability

MC9RS08KB4CSG is available at Aetrix Electronics and suitable for smart sensor nodes, industrial control interfaces, and consumer appliance controllers requiring stable component supply, long-term lifecycle support, and consistent parametric performance across temperature and voltage ranges.

Supply support for MC9RS08KB4CSG 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 specializing in secure connectivity solutions for automotive, industrial, and IoT markets, with roots in Freescale's embedded MCU heritage.

The MC9RS08KB4CSG belongs to the RS08 family - designed for ultra-low-cost, ultra-low-power 8-bit control applications where minimal footprint, single-wire debug, and robust analog integration are prioritized over raw performance.

FAQ

What is the maximum bus frequency supported by the MC9RS08KB4CSG?

The MC9RS08KB4CSG supports a maximum bus frequency of 10 MHz when using the internal clock source (ICS) with its frequency-locked loop (FLL). This is achievable across the full operating voltage range (1.8 V to 5.5 V) and temperature range (–40 °C to 85 °C). External crystal operation is limited to 16 MHz max but requires configuration through the XOSC module and is subject to stability constraints.

Does the MC9RS08KB4CSG include an integrated temperature sensor?

Yes, the MC9RS08KB4CSG includes an integrated 1.7 mV/°C temperature sensor accessible via the ADC. It is implemented as a dedicated ADC channel and operates in both Run and Stop modes, enabling ambient temperature monitoring without external components. Calibration data is not factory-trimmed, so system-level offset/gain compensation is required for accuracy.

What debug interface does the MC9RS08KB4CSG support?

The MC9RS08KB4CSG supports a single-wire background debug (BKGD) interface on PTA4, enabling in-circuit programming, real-time register inspection, and single breakpoint setting. This interface requires no dedicated debug header or additional pins beyond BKGD and ground, making it ideal for cost-sensitive and space-constrained designs where JTAG is impractical.

Can the MC9RS08KB4CSG operate from a 1.8 V supply?

Yes, the MC9RS08KB4CSG is fully specified to operate from 1.8 V to 5.5 V across –40 °C to 85 °C. At 1.8 V, it delivers up to 2.44 mA typical run current at 10 MHz bus frequency and maintains full functionality including ADC, ACMP, and peripheral operation. The minimum RAM retention voltage is 0.81 V, ensuring data integrity during brownout conditions.

How many ADC channels does the MC9RS08KB4CSG provide?

The MC9RS08KB4CSG provides 12 ADC input channels (ADP0–ADP11), all 10-bit resolution with 2.5 μs conversion time. These channels are distributed across PTA0–PTA3, PTB0–PTB3, and PTC0–PTC3. The ADC supports automatic compare, hardware triggering, and operation in Stop mode - allowing low-power periodic sampling without CPU intervention.