Overview
The LTC1968CMS8#PBF, produced by Analog Devices Inc., is a precision wide bandwidth RMS-to-DC converter. This component utilizes an innovative delta-sigma computational technique, offering high linearity and accuracy compared to conventional log-antilog RMS-to-DC converters. It is designed to operate with single-ended or differential input signals, supporting crest factors up to 4 and featuring a rail-to-rail common mode input range. The LTC1968 is ideal for applications requiring precise RMS measurements, such as in true RMS digital multimeters and panel meters.
Key Specifications
| Parameter | Value | Notes |
|---|---|---|
| Input Bandwidth | 500kHz (1% additional gain error), 150kHz (0.1% additional gain error) | Bandwidth independent of input voltage amplitude |
| Linearity | 0.02% | Allows simple system calibration |
| Input Type | Single-ended or differential | Rail-to-rail common mode voltage range up to 1VPEAK differential voltage |
| Output Type | Rail-to-rail output | Separate output reference pin for level shifting |
| Supply Voltage | 4.5V to 5.5V | Single power supply |
| Shutdown Current | 0.1µA | Low power shutdown mode |
| Package | 8-Pin MSOP | Space-saving package |
| Operating Temperature | –40°C to 85°C | Guaranteed functional over this range for LTC1968I, and from 0°C to 70°C for LTC1968C |
Key Features
- High Linearity and Accuracy: 0.02% linearity allows for simple system calibration and improved temperature behavior.
- Wide Input Bandwidth: Bandwidth up to 500kHz with 1% additional gain error and 150kHz with 0.1% additional gain error.
- No-Hassle Simplicity: True RMS-DC conversion with only one external capacitor using delta-sigma conversion technology.
- Flexible Inputs and Outputs: Supports single-ended or differential input signals and has a rail-to-rail output with a separate output reference pin for level shifting.
- Low Power Shutdown Mode: Ultralow shutdown current of 0.1µA.
- Compact Packaging: Space-saving 8-Pin MSOP package ideal for portable applications).
Applications
- True RMS Digital Multimeters and Panel Meters: Precise RMS measurements in various metering applications.
- True RMS AC + DC Measurements: Accurate measurements in both AC and DC environments).
- Portable Applications: The compact MSOP package makes it suitable for use in portable devices).
Q & A
- What is the input bandwidth of the LTC1968?
The input bandwidth of the LTC1968 is up to 500kHz with 1% additional gain error and 150kHz with 0.1% additional gain error).
- What is the linearity of the LTC1968?
The linearity of the LTC1968 is 0.02%, allowing for simple system calibration).
- Can the LTC1968 handle single-ended or differential input signals?
Yes, the LTC1968 can handle both single-ended and differential input signals).
- What is the supply voltage range for the LTC1968?
The supply voltage range for the LTC1968 is from 4.5V to 5.5V).
- What is the shutdown current of the LTC1968?
The shutdown current of the LTC1968 is 0.1µA).
- What type of package does the LTC1968 come in?
The LTC1968 comes in an 8-Pin MSOP package).
- What are the operating temperature ranges for the LTC1968?
The operating temperature range is –40°C to 85°C for LTC1968I and from 0°C to 70°C for LTC1968C).
- How does the LTC1968 achieve true RMS-DC conversion?
The LTC1968 achieves true RMS-DC conversion using delta-sigma conversion technology with only one external capacitor).
- Can the output of the LTC1968 be level-shifted?
Yes, the output of the LTC1968 can be level-shifted using the separate output reference pin).
- What are some common applications of the LTC1968?
Common applications include true RMS digital multimeters, panel meters, and true RMS AC + DC measurements).
