NXP Semiconductors MC9S08SH4MTG

Overview

MC9S08SH4MTG from Freescale Semiconductor is an 8-bit HCS08 microcontroller with 4 KB Flash, 256 B RAM, and a 20 MHz bus frequency. It integrates ADC (10-bit, 12-channel), SPI, I²C, SCI, two TPM modules, RTC, and ACMP, operating across -40°C to 105°C in a 24-pin QFN package. It targets low-power industrial control and sensor interface applications requiring embedded real-time response.

For engineers reviewing the MC9S08SH4MTG datasheet, MC9S08SH4MTG pinout, MC9S08SH4MTG application, or MC9S08SH4MTG equivalent, key selection criteria include Flash size, stop-mode current consumption, integrated analog peripherals, QFN thermal performance, and background debug interface support for rapid firmware iteration.

Technical Context

The MC9S08SH4MTG implements the HCS08 CPU core with HC08 instruction set extension and BGND instruction, supporting up to 32 interrupt/reset sources. Its Internal Clock Source (ICS) module includes a frequency-locked loop (FLL) with precision-trimmed internal reference enabling ±2% deviation over voltage and temperature.

Peripherals operate in Stop3 mode: ADC, ACMP, RTC, and SCI retain functionality with ultra-low power wake-up capability. The single-wire background debug interface enables in-circuit emulation with breakpoint support and 8-deep FIFO trace storage.

Key Specifications

Pinout & Package

MC9S08SH4MTG uses a 24-pin QFN package (98ASA00474D) with 0.5 mm pitch and exposed thermal pad for enhanced thermal dissipation in compact industrial layouts.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MC9S08SH4MTG, MC9S08SH8MTG offers double Flash/RAM in identical packaging for seamless upgrade, while S9KEAZ128AMLH provides ARM-based scalability at the cost of layout rework and toolchain transition.

Availability

MC9S08SH4MTG is available at Aetrix Electronics and suitable for industrial sensor nodes, smart HVAC actuators, programmable power monitors, and legacy protocol bridges requiring stable component supply and long-term industrial temperature support.

Supply support for MC9S08SH4MTG 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

Freescale Semiconductor (now part of NXP Semiconductors) designed high-reliability microcontrollers for automotive, industrial, and consumer applications before its 2015 acquisition.

The MC9S08SHx series targets cost-sensitive, low-power embedded control with integrated analog peripherals and robust debug infrastructure - optimized for space-constrained industrial modules and sensor endpoints.

FAQ

What is the maximum bus frequency supported by the MC9S08SH4MTG?

The MC9S08SH4MTG supports a maximum bus frequency of 20 MHz, enabled by its Internal Clock Source (ICS) module with Frequency-Locked Loop (FLL). This frequency is achievable across the full industrial temperature range (-40°C to +105°C) and supply voltage (2.7–5.5 V), as verified in the Electrical Characteristics section of the Rev. 3 datasheet. The MC9S08SH4MTG achieves this without requiring an external crystal when using the trimmed internal reference.

Does the MC9S08SH4MTG support debugging in-circuit without dedicated JTAG pins?

Yes, the MC9S08SH4MTG supports single-wire background debug via the BKGD/MS pin, eliminating the need for multi-pin JTAG headers. This interface enables breakpoint setting, memory inspection, and real-time register access during active operation. The on-chip debug module includes two comparators and nine trigger modes, with an 8-deep FIFO for storing program flow changes - all accessible through the MC9S08SH4MTG's single debug pin.

Can the MC9S08SH4MTG operate in ultra-low-power modes while retaining analog functionality?

Yes, the MC9S08SH4MTG supports Stop3 mode, where the ADC, ACMP, RTC, and SCI remain fully operational while CPU and most clocks are halted. In this mode, typical current draw is below 1 µA, and wake-up can occur on RTC overflow, ADC completion, ACMP output transition, or SCI start bit detection - making the MC9S08SH4MTG suitable for battery-powered sensing applications requiring periodic measurement without full system wake-up.

What package type and thermal characteristics does the MC9S08SH4MTG use?

The MC9S08SH4MTG uses a 24-pin QFN package documented under outline number 98ASA00474D: 4 mm × 4 mm body, 0.5 mm pitch, with an exposed thermal pad. This package replaces earlier gold-wire variants with copper-wire bonding per Freescale's QFN migration addendum. The exposed pad significantly improves thermal resistance, enabling reliable operation at 105°C ambient when soldered to a 4-layer PCB with adequate copper pour.

Is the MC9S08SH4MTG pin-compatible with other members of the SHx family?

Yes, the MC9S08SH4MTG shares identical 24-QFN pinout and signal mapping with MC9S08SH8MTG and MC9S08SH16MTG, as confirmed in the "Pins and Connections" chapter of the MC9S08SH8 Rev. 3 datasheet, which explicitly covers the MC9S08SH4. This allows hardware reuse across Flash variants - firmware and layout remain unchanged when upgrading from 4 KB to 8 KB or 16 KB Flash versions of the same package.