MC9S08GW64CLH - S08 8-bit MCU, 64KB Flash, 20MHz | NXP
MPN: MC9S08GW64CLH ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.97 | $6.97 |
| 10 | $6.62 | $66.20 |
| 100 | $6.27 | $627.00 |
| 500 | $5.96 | $2,980.00 |
| 1,000 | $5.66 | $5,660.00 |
MC9S08GW64CLH Overview
An 8-bit microcontroller (MCU) is a single-chip computer integrating a processor core, memory, and peripherals on one die. Within the power management and embedded control hierarchy, metering MCUs like the S08GW family sit between general-purpose 8-bit MCUs and dedicated metering ASSPs, offering meter-specific peripherals without sacrificing general I/O flexibility.
Key features include the S08 core running at up to 20MHz, 64KB (64K x 8) Flash with in-application reprogramming, a flexible clock system with FLL (frequency-locked loop) supporting FEI, FEE, FBE, FBI, FBELP, and FBILP modes, and two independent 16-bit SAR ADCs. A programmable delay block ties ADC sampling to flow-pulse events, enabling accurate quasi-synchronous sampling of pressure and temperature for gas-density compensation.
The device integrates typical metering peripherals: pulse counters with automatic quadrature/sensor decoding for reed, Hall, or optical flow sensors, plus serial communication (SCI/SPI/I2C-class peripherals on the S08 platform) for protocol handling in M-Bus, RF, and optical-head meter architectures. Low-power wait/stop modes support battery-powered water and gas meters with multi-year service life.
Typical applications are gas flow meters, water flow meters, single-phase electric energy meters, and heat-cost allocators. The dual-ADC architecture allows simultaneous sensing of voltage and current channels in single-phase energy measurement.
Design consideration: when the FLL reference source, reference divider, or trim value changes, or when moving between FLL-disabled and FLL-enabled modes, the clock specification applies per the manufacturer datasheet; allow settling time in software. If a crystal or resonator is used as the reference, ensure it is already running before mode transitions.
This page synthesizes distributor pricing, drop-in alternatives, lifecycle (End-of-Life per NXP), and practical design notes not found in the manufacturer datasheet, verified as of 2026-10-10.
Drop-in alternatives for MC9S08GW64CLH — 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 MC9S08GW64CLH (same form factor and footprint) — differing in Package, Core, ADC, Operating Temperature Range, Peripherals.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
MC9S08GW48CLH
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
MC9S08GW32CLH
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$5.1 / Unit
View Datasheet →MC9S08PA60VLH
✅ Drop-In📋 Reference alternative (not in catalog)
MC9S08PT60VLH
✅ Drop-In✓ In Stock
$3.65 / Unit
View Datasheet →Z8F6402AR020EC
✅ Drop-In📋 Reference alternative (not in catalog)
MC9S08GW64CLH Maximum Ratings & Electrical Characteristics
| Core | S08 (8-bit) |
| Core Size | 8-bit |
| Maximum Clock Frequency | 20 MHz |
| Flash Memory | 64 KB (64K x 8) |
| ADC Count | 2 independent 16-bit SAR ADCs |
| Special Peripherals | Pulse counter with automatic sensor decoding, programmable delay block |
| Clock Modes | FEI, FEE, FBE, FBI, FBELP, FBILP (FLL-based) |
| Package | 64-LQFP (10 x 10 mm) |
| Mounting Type | Surface Mount |
| Target Applications | Gas/water flow meters, single-phase electric meters |
| Product Family | MC9S08GW (S08GW) |
| Supplier Device Package | 64-LQFP |
MC9S08GW64CLH 64-lqfp Pin Configuration Guide
Pin configuration for MC9S08GW64CLH (64-lqfp 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 MC9S08GW64CLH.
Refer to the datasheet for full pin configuration.
Typical Applications
MC9S08GW64CLH is suitable for 6 applications: Gas Flow Meter, Water Flow Meter, Single-Phase Electric Energy Meter, Heat Cost Allocator and Thermal Energy Sensing, Sensor Data Acquisition Nodes, EOL Last-Time-Buy Replacement Programs.
Gas Flow Meter
The MC9S08GW64CLH fits gas flow meters because its pulse counter with automatic sensor decoding directly interfaces reed, Hall-effect, or optical flow sensors without continuous CPU polling, and its dual independent 16-bit SAR ADCs with a programmable delay block can quasi-synchronously sample pressure and temperature sensors for gas-density compensation. In a typical architecture, the MCU counts low-frequency flow pulses in a low-power stop mode, wakes on pulse edges, and applies density correction using ADC channels at 16-bit resolution. Because pulse decoding is handled in hardware, average current drops sharply compared with software polling, extending multi-year lithium-battery life. The 64KB Flash accommodates communication stacks and dense compensation tables. Designers should verify stop-mode current and FLL mode-transition timing in the official datasheet when optimizing battery budget.
Recommended
Water Flow Meter
For water flow meters, the MC9S08GW64CLH offers hardware pulse counting with automatic sensor decoding for mechanical reed-switch or Hall-based register outputs, letting the S08 core remain in stop mode between events. The dual 16-bit SAR ADCs allow temperature sensing for hot-water meters and diagnostic monitoring of battery voltage simultaneously and independently. The programmable delay block aligns ADC sampling windows with pulse events, improving measurement repeatability. The 64KB Flash supports multi-protocol communication heads (optical, M-Bus-class, or RF module interfacing) and calibration tables per meter size. Because the family was explicitly designed for water and gas flow metering, the peripheral set removes the software overhead a general-purpose 8-bit MCU would need, simplifying certification-relevant code. Confirm wake-up latency and pulse input glitch filtering limits against the NXP MC9S08GW64 datasheet.
Recommended
Single-Phase Electric Energy Meter
In single-phase electric meters, the MC9S08GW64CLH's two independent 16-bit SAR ADCs are the defining advantage: one ADC can sample the voltage channel while the other samples the current channel, enabling simultaneous or precisely delayed (via the programmable delay block) acquisition needed for accurate RMS power and energy computation. The 20MHz S08 core executes fixed-point metering firmware including phase compensation and creep detection. 64KB Flash stores tariff tables, load-profile logs, and communication firmware for optical or serial metrological interfaces. Because NXP designed the GW family specifically for single-phase electric meters, reference-grade timing of the dual ADCs removes the need for an external sample-and-hold or a dedicated metering ASSP in simpler meter classes. Validate ADC integral nonlinearity and reference configuration in the official datasheet for the accuracy class targeted.
Recommended
Heat Cost Allocator and Thermal Energy Sensing
Heat cost allocators and compact thermal-energy devices benefit from the MC9S08GW64CLH's dual 16-bit SAR ADCs, which can independently read two temperature sensors (supply and return lines) plus reserve channels for battery monitoring. The programmable delay block ensures that both temperature channels are sampled within a tight time window, reducing error from thermal drift between conversions - important because the heat quantity computation is proportional to the temperature difference, which is a small number compared to the absolute temperatures. The pulse counter decodes flow-meter pulses in hardware while the S08 core sleeps, conserving the coin-cell or lithium battery typical of these devices. The 64KB Flash accommodates integration algorithms and EN-style calculation tables. Confirm ADC input impedance effects on high-impedance NTC dividers in the NXP datasheet.
Recommended
Sensor Data Acquisition Nodes
Beyond utility meters, the MC9S08GW64CLH works well as an 8-bit sensor acquisition node where two analog channels must be read with real 16-bit resolution - for example pressure-temperature nodes, battery monitoring units, or industrial transducer interfaces. The two independent SAR ADCs can run different sampling schedules concurrently, something single-ADC 8-bit MCUs cannot do without multiplexing artifacts. The programmable delay block synchronizes conversions with external events (counter triggers), which suits vibration or flow-correlated measurements. SCI/SPI/I2C-class serial peripherals on the S08 platform forward processed data to a host or radio module. The 20MHz bus speed and 64KB Flash allow modest digital filtering without an external DSP. For such reuse designs, remember the part is EOL; design in the GW48/GW32 variants for future supply flexibility.
Recommended
EOL Last-Time-Buy Replacement Programs
Because NXP has marked the MC9S08GW64CLH as End-of-Life, a major current 'application' of this part is lifecycle management: last-time-buy consolidation and bridging existing meter fleets until a redesign lands. Remaining inventory at independent distributors (about 6,768 pieces at Heisener as of 2026-10-10) and Rochester Electronics' licensed manufacturing channel can cover bridge quantities. For pin-to-pin continuity on the same PCB, the same-family MC9S08GW48CLH and MC9S08GW32CLH share the S08GW die architecture and 64-LQFP footprint with reduced Flash, and firmware must fit the smaller memory. For redesign-level moves, general-purpose S08 parts (MC9S08PT60VLH) or other cores require layout and firmware changes. Verify the official NXP Discontinuance and Replacement Product Change Notice for final-order deadlines.
Recommended
Recommended Products Summary
Engineering reference data for MC9S08GW64CLH — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | MC9S08GW48CLH | MC9S08GW32CLH | MC9S08PT60VLH | Z8F6402AR020EC |
|---|---|---|---|---|---|
| Package | 64-LQFP (10x10 mm) | 64-LQFP (10x10 mm) | 64-LQFP (10x10 mm) | 64-LQFP | 64-LQFP |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | Zilog |
| Core | S08 (8-bit) | S08 (8-bit) | S08 (8-bit) | S08 (8-bit) | Z8 Encore! XP (8-bit) |
| Flash Memory | 64 KB (64K x 8) | 48 KB | 32 KB | 60 KB | 64 KB |
Key Differentiators
- Dual independent 16-bit SAR ADCs (vs MC9S08PT60VLH)
- Hardware pulse counter with automatic sensor decoding (vs MC9S08PT60VLH)
- Full 64KB Flash vs same-family variants (vs MC9S08GW48CLH)
Design Notes
Clock mode transitions are the most common source of erratic behavior on the S08GW. Per the NXP MC9S08GW64 datasheet, the timing specification applies whenever the FLL reference source or reference divider changes, the trim value changes, or the system moves between FLL-disabled (FBELP, FBILP) and FLL-enabled (FEI, FEE, FBE, FBI) modes. If a crystal or resonator is the reference, the specification assumes it is already running - wait for oscillation stabilization before switching modes, and re-trim after any reference change in firmware.
For battery-powered gas/water meters, exploit the hardware pulse counter so the core stays in stop mode between flow pulses; software polling of the pulse input prevents entry into the lowest-power states. Wake on pulse edge, sample the pressure/temperature ADC channels via the programmable delay block, then return to stop. Verify actual stop-mode and running-mode currents in the official datasheet Electrical Characteristics chapter - this page does not reproduce current figures - and budget crystal startup time on each wake when computing average battery drain.
The dual 16-bit SAR ADCs achieve their resolution only with clean analog supply and reference domains. Separate the analog ground for the ADC reference path from the digital return of the pulse-counter inputs, which switch aggressively with reed/Hall sensor debounce. Keep the VREF trace short and decouple per the datasheet reference design. For single-phase energy metering, sample the voltage and current channels through the programmable delay block with a fixed, calibrated offset - do not rely on back-to-back software-triggered conversions if phase error matters to the accuracy class.
Compliance Information
Compliance status not captured in the verified web data. Confirm on the official NXP MC9S08GW64CLH product page (Environmental Quality section) or via distributor certificate of compliance before order release.
