MCP3918 - 3V Single-Channel Analog Front End

Q: What are the main functions integrated in the MCP3918?

It integrates a single delta-sigma ADC, a programmable gain amplifier (PGA), phase delay compensation, a low-drift internal voltage reference, and digital offset/gain calibration registers.

Q: How can the MCP3918 communicate with a microcontroller?

It supports a flexible serial interface including SPI and a simple two-wire interface, with an additional Data Ready pin that can be connected to an MCU interrupt request (IRQ).

Q: What security mechanisms does the MCP3918 provide for communications and configuration?

It uses 16-bit CRC-16 checksums for secure data transfers and register map static configuration, plus a register map lock controlled by an 8-bit secure key to prevent unwanted WRITE commands.

Sep 17, 2026

Upload by Nguyễn Văn Học

MCP3918 is a 3V single-channel analog front end integrating a delta-sigma ADC, programmable gain amplifier (PGA), phase delay compensation, low-drift internal voltage reference, and digital offset/gain calibration registers. It supports configurable ADC resolution (16-/24-bit), oversampling ratio up to 4096, gain up to 32x, dithering and auto-zeroing, and flexible SPI or two-wire serial communication with a dedicated Data Ready pin. Security is provided via CRC-16 checksums and an 8-bit register map lock, targeting applications such as polyphase shunt energy meters and power measurement.

LanguageEnglish

CategoryTechnology

FormatPDF

Pages88

Reading Time3 h 42 min

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Features

Description

Applications

Package Type

Electrical Characteristics

Absolute Maximum Ratings

Electrical Specifications (Analog Specifications)

MCP3918 3V Single-Channel Analog Front End Features: • One 24-Bit Resolution Delta-Sigma A/D Converter • 93.5 dB SINAD, -107 dBc Total Harmonic Distortion (THD) (up to 35th harmonic), 112 dB Spurious-Free Dynamic Range (SFDR) • Flexible Serial Interface that Includes Both SPI and a Simple Two-Wire Interface Ideal for Polyphase Shunt Energy Meters • Advanced Security Features: - 16-Bit Cyclic Redundancy Check (CRC) Checksum on All Communications for Secure Data Transfers - 16-Bit CRC Checksum and Interrupt Alert for Register Map Configuration - Register Map Lock with 8-Bit Secure Key • 2.7V-3.6V AV DD , DVDD • Programmable Data Rate, Up to 125 ksps: - 4 MHz Maximum Sampling Frequency - 16 MHz Maximum Master Clock • Oversampling Ratio, Up to 4096 • Ultra Low-Power Shutdown Mode with < 10 µA • Low-Drift 1.2V Internal Voltage Reference: 9 ppm/°C • Differential Voltage Reference Input Pins • High-Gain Programmable Gain Amplifier (PGA)(up to 32 V/V) • Phase Delay Compensation with 1 µs Time Resolution • Separate Data Ready Pin for Easy Synchronization • Individual 24-Bit Digital Offset and Gain Error Correction • High-Speed 20 MHz SPI Interface with Mode 0,0 and 1,1 Compatibility • Continuous Read/Write Modes for Minimum Communication with Dedicated 16-/32-Bit Modes • Available in 20-Lead QFN and SSOP Packages • Extended Temperature Range: -40°C to +125°C (all specifications are valid down to-45°C) Description: The MCP3918 is a 3V single-channel Analog Front End (AFE), containing one Delta-Sigma Analog-to-Digital Converter (ADC), one Programmable Gain Amplifier (PGA), phase delay compensation block, low-drift internal voltage reference, digital offset and Gain Error Calibration registers, and high-speed 20 MHz SPI compatible serial interface. The MCP3918 ADC is fully configurable with features such as: 16-/24-bit resolution, Oversampling Ratio (OSR) from 32 to 4096, gain from 1x to 32x, independent shutdown and Reset, dithering and auto-zeroing. Communication is largely simplified with 8-bit commands, including various continuous Read/Write modesand 16-/24-/32-bit data formats that can be accessed by the Direct Memory Access (DMA) of an 8, 16 or 32-bit MCU, and with the separate Data Ready pin that can directly be connected to an Interrupt Request (IRQ) input of an MCU. The MCP3918 includes advanced security features to secure the communications and the configuration settings, such as a CRC-16 checksum on both serial data outputs and on the register map static configuration. It also includes a register map lock through an 8-bit password to avoid the processing of any unwanted WRITE commands. For polyphase shunt-based energy meters, the MCP3918 two-wire serial interface greatly reduces system cost, requiring only a single bidirectional isolator per phase. The MCP3918 is capable of interfacing a variety of voltage and current sensors, including shunts, Current Transformers (CTs), Rogowski coils and Hall effect sensors. Applications: • Single-Phase and Polyphase Energy Meters • Energy Metering and Power Measurement • Automotive • Portable Instrumentation • Medical and Power Monitoring • Audio/Voice Recognition • Isolator Sensor Application 􀂤 2014-2020 Microchip Technology Inc. DS20005287C-page 1 MCP3918 Package Type | MCP3918
SSOP | CH0+
CH0-
NC
NC
AGND | MCP3918
4 x 4 QFN* | SCK/MCLK
CS/BOOST OSC2/MODE OSC1/CLKI/GAIN0 DR/GAIN1 | | --- | --- | --- | --- | |
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SDI/OSR1
SDO
SCK/MCLK CS/BOOST OSC2/MODE
OSC1/CLKI/GAIN0 DR/GAIN1
MDAT0
NC
DGND
| | AVDD
DVDD
RESET/OSR0 SDI/OSR1 SDO | | | | |
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REFIN+/OUT
REF INDG ND NC MDAT0 | | | * Includes Exposed Thermal Pad (EP); see

FAQs

What are the main functions integrated in the MCP3918?

It integrates a single delta-sigma ADC, a programmable gain amplifier (PGA), phase delay compensation, a low-drift internal voltage reference, and digital offset/gain calibration registers.

How can the MCP3918 communicate with a microcontroller?

It supports a flexible serial interface including SPI and a simple two-wire interface, with an additional Data Ready pin that can be connected to an MCU interrupt request (IRQ).

What security mechanisms does the MCP3918 provide for communications and configuration?

It uses 16-bit CRC-16 checksums for secure data transfers and register map static configuration, plus a register map lock controlled by an 8-bit secure key to prevent unwanted WRITE commands.

Sep 17, 2026

Upload by Nguyễn Văn Học