Renesas' robust and highly accurate digital power monitor (DPM) family offers a high level of integration and a range of capability including high common mode voltage support, full featured bidirectional, high-side and low-side digital current sense, and voltage monitors with fast interrupts and serial interface.

What are Digital Power Monitors?

Digital power monitors are integrated solutions that provide high-side, low-side, and bidirectional current monitoring, as well as voltage monitoring, and use an on board ADC to provide digital feedback.

Digital power monitors can be used with a battery, DC motor or the loading of the circuit. Knowing the amount of current flow is important for performing such features as:

  • Battery charging
  • Motor speed control
  • Short circuit detection

Amplifiers are used in applications to measure the amount of current flow through a circuit. An amplifier is used to amplify the voltage developed by the current sense so it can properly drive the ADC.

Digital power monitors integrate the amplifier and ADC into a single IC to measure both current and voltage and now provides digital output to the microcontroller or FPGA.

Example of a Digital Power Monitor Circuit

Example of a Digital Power Monitor Circuit

Digital Power Monitor Applications

Power Systems

A primary application for a DPM is to measure current, voltage and power in a power system. The 0V to 60V input voltage range works well in circuit breaker and system health applications.

In the example circuit, a principal ISL28025 DPM monitors the regulated 12V to 60V line that feeds several power subsystems, and additional ISL28025 devices are used to monitor a lower regulated voltage and individual loads.

Power modules are also added to the circuit for high current point of load applications. The ISL28023 and the ISL28025 follow the PMBus industry-standard protocol, simplifying the coding required for communication.

The SMBAlert line provides quick feedback if a threshold is crossed, indicating a problem in the circuit and allowing easy identification of the problem area. A second SMBAlert line is also used to shut down the main power through analog components for an even faster response time.

For more application design ideas, see AN1955: Design Ideas for Intersil Digital Power Monitors (PDF).

Power System Application Circuit

Power System Application Circuit

Alternatives

Renesas' family of DPMs includes the ISL28023 full featured digital power monitor and the ISL28025 digital power monitor in a tiny package.

If analog output voltage is required, please also see our ISL28005 low cost alternative and ISL28006 high-performance current sense amplifier products.

ドキュメント&ダウンロード

タイトル 他の言語 分類 形式 サイズ 日付
アプリケーションノート、ホワイトペーパー
Sensing Elements for Current Measurements 简体中文 ホワイトペーパー PDF 413 KB
AN1993: Voltage Feedback versus Current Feedback Operational Amplifiers アプリケーションノート PDF 564 KB
AN1955: Design Ideas for Intersil Digital Power Monitors アプリケーションノート PDF 1.32 MB
AN1694: The Four Basic Building Blocks of an Op Amp アプリケーションノート PDF 357 KB
その他資料
Analog ICs Brochure カタログ PDF 4.19 MB
TB514: Operational Amplifier Basics その他資料 PDF 519 KB