MKM34Z256VLQ7 - 75MHz Cortex-M0+ Metrology MCU | NXP
MPN： MKM34Z256VLQ7 ✓ 啟用中MKM34Z256VLQ7 概覽
A metrology MCU is a class of microcontroller purpose-built for electricity, gas, and water measurement infrastructure. Within the system hierarchy, it sits at the level of microcontroller unit (MCU) -> 32-bit MCU -> ARM Cortex-M based MCU -> metrology application MCU, combining a general-purpose processor core with measurement-oriented analog peripherals and security features that general-purpose MCUs typically lack.
Key features include the 256 KB on-chip flash with 32 KB SRAM for protocol stacks and data logging, an auto-compensated internal real-time clock (iRTC) with hardware tamper detection and time stamping, a high-precision internal voltage reference with low temperature drift, and a segment LCD controller for meter displays. The ARM Cortex-M0+ core delivers energy-efficient 32-bit processing with a compact instruction set suitable for real-time metrology computation.
Technically, the KM3x family is designed to enable single-chip one-, two-, and three-phase electricity meters: the integrated AFE samples voltage and current channels, the Cortex-M0+ executes metering algorithms, and the tamper module supports both active and passive tamper detection, a requirement for modern billing-grade metering security.
Typical applications include three-phase smart electricity meters, flow meters for water and gas, and other precision measurement instruments where a calibrated reference and tamper evidence are mandatory. The segment LCD interface directly drives meter display glass without a separate LCD driver.
Design consideration: the device is offered in Tray packaging for this orderable part; verify flash and SRAM margins before committing firmware, as the KM3x family also spans 128 KB and 512 KB flash variants in the same footprint.
This page synthesizes distributor pricing data, drop-in family alternatives, and practical design notes not found in the manufacturer datasheet alone.
直接替換替代品，適用於 MKM34Z256VLQ7 — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： MKM34Z256VLQ7 （相同外形與佔位） — 差異在於 Security Features, Internal Voltage Reference, Package, ADC, RoHS Status.
MKM34Z256VLL7
✅ 直接替換📋 參考替代品（不在目錄中）
MKM34Z512VLQ7
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MKM34Z128VLQ7
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MKM34Z128VLL7
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MKM33Z256VLQ7
✅ 直接替換 ⚠️ 規格未經驗證📋 參考替代品（不在目錄中）
MKM34Z256VLQ7 最大額定值與電氣特性
| Core Processor | ARM Cortex-M0+ |
| Core Size | 32-Bit |
| 最大時脈頻率 | 75 MHz |
| Flash Memory | 256 KB (256K x 8) |
| SRAM | 32 KB |
| 供應電壓 | 2.5 V / 3.3 V |
| 封裝 | 144-LQFP (20 x 20 mm) |
| 安裝類型 | Surface Mount |
| Peripherals | Segment LCD controller, iRTC with hardware tamper detection |
| Analog Front End | Integrated metrology AFE |
| Internal Voltage Reference | High-precision, low temperature drift |
| Security Features | Active and passive tamper detection with time stamping |
| Family | Kinetis KM34 (KM3x) |
| Target Applications | 1-, 2-, 3-phase electricity meters, flow meters |
| Packaging | Tray |
MKM34Z256VLQ7 144-lqfp (20 x 20 mm) 腳位配置指南
MKM34Z256VLQ7（144-lqfp (20 x 20 mm) 封裝）的腳位配置。 此數位 IC 包含 GPIO、通訊介面（UART、SPI、I2C）與電源腳位。替代腳位功能與配置選項請參閱製造商資料表。對嵌入式系統設計與 PCB 佈局至關重要。
無詳細腳位定義資料： MKM34Z256VLQ7.
請參閱 資料表 以查看完整腳位配置。
典型應用
MKM34Z256VLQ7 適用於 6 應用s: Three-Phase Smart Electricity Meters, Single-Phase Residential Energy Meters, Water and Gas Flow Meters, Industrial Submetering and Panel Meters, Smart Grid Data Concentrators and Edge Nodes, Precision Measurement and Data Logging Instruments.
Three-Phase Smart Electricity Meters
The MKM34Z256VLQ7 is purpose-built for three-phase electricity metering: NXP states the KM3x family enables single-chip one-, two-, and three-phase meters. The integrated analog front end samples voltage and current channels from all three phases, the 75 MHz Cortex-M0+ core executes metering algorithms such as RMS, power, and energy accumulation, and the 256 KB flash holds billing firmware plus DLMS/COSEM-style protocol code. The auto-compensated iRTC provides tariff timekeeping while hardware tamper detection with timestamping satisfies anti-fraud requirements for billing-grade meters. Placed as the sole processor, it eliminates a separate metrology ASIC and a separate MCU, cutting BOM cost and calibration complexity in a 144-LQFP 20 x 20 mm footprint.
推薦
Single-Phase Residential Energy Meters
For single-phase residential meters, the MKM34Z256VLQ7 integrates everything needed on one chip: the metrology AFE measures line voltage and neutral/current channels, the low-drift internal voltage reference keeps energy accuracy stable across temperature, and the segment LCD controller directly drives the meter display glass without an external LCD driver, reducing component count. The 2.5 V/3.3 V supply range suits mains-derived auxiliary power supplies, and low-power modes support billing during power-outage conditions. The 256 KB flash accommodates firmware, calibration tables, and communication firmware for AMI (advanced metering infrastructure) networks, while active/passive tamper detection with timestamps records intrusion events required by regional metering standards for billing integrity.
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Water and Gas Flow Meters
NXP explicitly positions the KM3x family for flow meters and other precision measurement applications. In a water or gas flow meter, the MKM34Z256VLQ7 reads pulse or analog sensor outputs through its analog front end, integrates consumption over time using the auto-compensated internal RTC, and displays volume on a segment LCD driven directly by the on-chip controller. The high-precision, low-temperature-drift voltage reference is critical here: battery-powered flow meters must hold measurement accuracy across outdoor temperature ranges for years without recalibration. Low power features extend battery life, while the 144-LQFP package offers ample I/O for valve control, communication interfaces, and service tooling in a single-chip design.
推薦
Industrial Submetering and Panel Meters
In industrial submetering, panel energy meters, and power-quality monitors, the MKM34Z256VLQ7 provides the measurement core: its AFE digitizes voltage and current channels, the Cortex-M0+ at 75 MHz computes per-phase power parameters, and the timestamping RTC correlates consumption events for tenant billing or machine-level energy accounting. The 144-LQFP package supplies enough GPIO and serial interfaces for RS-485/Modbus transceivers, relays, and pushbuttons. The 256 KB flash stores multiple tariffs, load profiles, and calibration data. Hardware tamper detection also protects commercial submetering installations, where unauthorized access has direct financial impact, and the segment LCD supports local kWh indication required by panel-meter form factors.
推薦
Smart Grid Data Concentrators and Edge Nodes
In smart grid edge nodes, the MKM34Z256VLQ7 serves as a secure measurement and telemetry processor. Its tamper detection with timestamps and security protection suite help harden field-deployed equipment, while the 256 KB flash runs data aggregation firmware and communication stacks. The 75 MHz Cortex-M0+ handles protocol parsing and CRC/encryption-lite tasks, and multiple serial interfaces from the KM34 family connect to RF modules or PLC modems for AMI backhaul. The 2.5 V/3.3 V operation simplifies integration with standard industrial power rails, and low-power modes allow battery-backed operation through supply interruptions. Its segment LCD controller can present local status diagnostics during commissioning and maintenance visits.
推薦
Precision Measurement and Data Logging Instruments
Beyond metering, the KM34's combination of a low-drift voltage reference, RTC with auto-compensation, and generous I/O makes the MKM34Z256VLQ7 a strong fit for precision measurement instruments and data loggers. The internal reference anchors ADC measurements without an external precision reference in many designs, the iRTC timestamps every logged sample for regulatory traceability, and the segment LCD displays readings and diagnostics in handheld or panel-mounted instruments. The 144-LQFP 20 x 20 mm package provides sufficient pins for sensor multiplexers, keypad scanning, and communication ports. The 32 KB SRAM buffers logging data between communication sessions, and 256 KB flash stores lookup tables and multi-parameter firmware.
推薦
推薦產品摘要
工程參考資料，適用於 MKM34Z256VLQ7 — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | MKM34Z256VLL7 | MKM34Z512VLQ7 | MKM34Z128VLQ7 | MKM33Z256VLQ7 |
|---|---|---|---|---|---|
| Package | 144-LQFP (20 x 20 mm) | 144-LQFP (20 x 20 mm) - same | 144-LQFP (20 x 20 mm) - same | 144-LQFP (20 x 20 mm) - same | 144-LQFP (20 x 20 mm) - same |
| Brand | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors | NXP Semiconductors |
| Core | ARM Cortex-M0+ @ 75 MHz | ARM Cortex-M0+ @ 75 MHz | ARM Cortex-M0+ @ 75 MHz | ARM Cortex-M0+ @ 75 MHz | ARM Cortex-M0+ @ 75 MHz |
| Flash Memory | 256 KB | 256 KB | 512 KB | 128 KB | 256 KB |
| Metrology AFE / Tamper Detection | Yes (integrated AFE, active/passive tamper, iRTC) | Yes (identical) | Yes | Yes | Reduced analog feature set (KM33 sub-family) |
主要差異化特點
- Balanced 256 KB flash for billing metering firmware (對比MKM34Z128VLQ7)
- Memory headroom for field firmware updates (對比MKM34Z512VLQ7)
- Full KM34 metrology analog feature set (對比MKM33Z256VLQ7)
設計說明
The 144-LQFP (20 x 20 mm) footprint uses 0.5 mm pitch gull-wing leads. Follow NXP's KM34 hardware design guidance: use a solid ground plane on layer 2, place 100 nF ceramic decoupling capacitors at every VDD pin pair with a bulk 10 uF capacitor near the main supply entry, and route the analog front end (AFE) input traces short and away from switching signals to preserve measurement accuracy. Keep crystal/iRTC oscillator traces guarded and short, since RTC accuracy directly affects billing-grade energy accumulation.
Do not treat the KM34 as a general-purpose MCU: its analog front end and tamper module require configuration through the KM34 reference manual, and tamper event handling must be designed into firmware from the start (retrofitting tamper logic often fails certification review). Also, metering accuracy depends on the internal voltage reference calibration - apply the factory calibration values from flash and validate drift across the expected temperature range during design verification, per NXP metering reference design practice.
The MKM34Z256VLQ7 operates from a 2.5 V or 3.3 V supply. For battery-backed or outage-tolerant meter designs, size the backup supply for the low-power modes documented in the KM34 datasheet rather than for active 75 MHz operation; the iRTC and tamper monitor must stay alive during main-supply loss. Estimated: verify measured active-mode current against the datasheet electrical table on your own board, as current depends strongly on clock configuration and AFE usage.
When driving the segment LCD, follow the LCD drive voltage recommendations in the NXP datasheet and route segment traces with reasonable spacing to avoid ghosting; use the recommended LCD frame frequency from the reference manual. For production, NXP's KM3x enablement suite (reference designs and driver libraries) should be used as the starting point to shorten certification time for metering applications.
合規資訊
Compliance data was not captured in the verified web data for this part. NXP's official product page for MKM34Z256VLQ7 contains Environmental & Quality sections with authoritative RoHS/REACH information; consult it and NXP product change notices before production.