NXP Semiconductors MKM35Z256VLQ7R

Overview

MKM35Z256VLQ7R from NXP Semiconductors is a 32-bit Arm® Cortex®-M0+ microcontroller optimized for high-accuracy electricity metering, featuring four 24-bit ΣΔ ADCs with programmable gain amplifiers, 256 KB flash/64 KB SRAM, hardware tamper detection with timestamping, and integrated segment LCD controller. It enables single-chip 1-/2-/3-phase metering designs compliant with WELMEC/OIML recommendations.

For engineers reviewing the MKM35Z256VLQ7R datasheet, MKM35Z256VLQ7R pinout, MKM35Z256VLQ7R application, or MKM35Z256VLQ7R equivalent, this page delivers verified metrology-grade MCU specifications, low-power operation down to 261 nA deep sleep, iRTC with battery backup, and secure boot via MMCAU AES acceleration - all validated against NXP's KM35P144M75SF0 reference design and Rev. 2 (March 2020) data sheet.

Technical Context

The MKM35Z256VLQ7R integrates a dedicated Metering Memory Mapped Arithmetic Unit (MMAU) for real-time energy computation and a hardware-based tamper detection system that timestamps events in the VBAT domain. Its analog front end includes four independent ΣΔ ADC channels with PGA, each supporting up to 6.5 MHz modulator clock and 24-bit resolution, enabling simultaneous voltage/current sampling for metrology-grade accuracy.

It implements a multi-layer security architecture comprising Memory Protection Unit (MPU), CRC engine, MMCAU AES-128 accelerator, RNGA compliant with NIST SP800-90, and 80-bit unique chip ID. Clocking is managed by the MCG module supporting FLL, PLL, and multiple internal references (32 kHz, 4 MHz, 1 kHz LPO), with precise 32.768 kHz crystal oscillator support in the iRTC power domain.

Key Specifications

Pinout & Package

Package: 144-pin LQFP (20 mm × 20 mm, 0.5 mm pitch), JEDEC MS-026AC, moisture sensitivity level 3, lead-free per RoHS.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar electricity metering applications.

Compared with MKM35Z256VLQ7R, MKM35Z256VLL7R offers identical metrology capability in a smaller footprint but reduced I/O count, while MC56F84789 demands external analog components and lacks hardware tamper logging - making MKM35Z256VLQ7R the sole option for fully integrated, standards-compliant, tamper-evident metering.

Availability

MKM35Z256VLQ7R is available at Aetrix Electronics and suitable for smart electricity metering, revenue-grade energy monitoring, prepayment metering, AMI endpoint nodes, and industrial power quality analyzers requiring stable component supply across extended temperature and long product lifecycles.

Supply support for MKM35Z256VLQ7R 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 applications, with over 30 years of expertise in microcontrollers and metering ICs.

The KM35 sub-family - including MKM35Z256VLQ7R - was designed specifically for single-chip, high-accuracy, secure electricity metering systems meeting international metrology standards (IEC 62053, OIML R46) and utility cybersecurity mandates.

FAQ

What is the maximum operating frequency of the MKM35Z256VLQ7R core?

The MKM35Z256VLQ7R features an Arm® Cortex®-M0+ core rated for up to 75 MHz operation under normal run mode conditions. This frequency is supported across the full industrial temperature range (–40 °C to +105 °C) and supply voltage range (2.7–3.6 V) when the AFE is active. The core can also operate at reduced frequencies (e.g., 4 MHz) in Very-Low-Power Run (VLPR) mode to minimize dynamic power consumption while maintaining real-time responsiveness for metrology tasks.

Does the MKM35Z256VLQ7R support hardware-based tamper detection with timestamping?

Yes, the MKM35Z256VLQ7R includes four dedicated TAMPERx input pins with hardware tamper detection logic that operates independently in the VBAT domain. Each detected tamper event is automatically timestamped using the iRTC counter and stored in tamper memory retained during main power loss. This functionality complies with IEC 62056-21 physical security requirements and is validated in NXP's KM35P144M75SF0 reference design.

What analog-to-digital converter resources does the MKM35Z256VLQ7R provide for metering applications?

The MKM35Z256VLQ7R integrates four independent 24-bit ΣΔ ADC channels with programmable gain amplifiers (PGA), each capable of 6.5 MHz modulator clock operation and >99 dB SNR. It also includes a 16-channel 16-bit SAR ADC with four result registers for auxiliary measurements, plus a high-speed analog comparator with integrated 6-bit DAC and programmable reference - collectively enabling simultaneous voltage, current, and neutral monitoring in 1-/2-/3-phase configurations.

Is the MKM35Z256VLQ7R qualified for extended temperature operation in utility metering environments?

Yes, the MKM35Z256VLQ7R is specified for ambient operating temperatures from –40 °C to +105 °C, with junction temperature limits up to +125 °C. Its thermal resistance (RθJA = 41.7 °C/W for 144-LQFP) and voltage regulation stability across this range - particularly the 2.7–3.6 V AFE supply window - are validated per JEDEC JESD51-2A and meet utility industry requirements for outdoor and enclosed meter deployments per IEC 62059-31-1.

How does the MKM35Z256VLQ7R implement secure firmware and data protection?

The MKM35Z256VLQ7R implements layered security including a Memory Protection Unit (MPU), programmable Cyclic Redundancy Check (PCRC), Memory Mapped Cryptographic Acceleration Unit (MMCAU) supporting AES-128 encryption/decryption, and a NIST SP800-90-compliant Random Number Generator (RNGA). These features enable secure boot, encrypted firmware updates, and protected metering data storage - satisfying DLMS/COSEM and IEC 62351-8 cybersecurity requirements for smart grid endpoints.