Overview
The AD637JR is a high-precision, wideband RMS-to-DC converter produced by Analog Devices Inc. This component is designed to compute the true root mean square (RMS) value of any complex waveform, providing an accurate representation of the input signal's power. It operates from a single or dual polarity power supply, handling both AC and DC input signals, and is well-suited for applications requiring precise RMS measurements such as power monitoring, audio/video equipment, and industrial instrumentation.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Operating Voltage Range | ±3 V | ±18 V | V | |
| Supply Current | 2.2 mA | mA | ||
| Offset Voltage | ±1 mV | ±0.5 mV | ±1 mV | mV |
| Temperature Range (Grade J) | 0°C | 70°C | °C | |
| Temperature Range (Grade A/B) | -40°C | +85°C | °C | |
| Temperature Range (Grade S) | -55°C | +125°C | °C | |
| Dynamic Range | 60 dB | dB | ||
| Frequency Response | DC to 1 MHz | |||
| Package Type | 16-SOIC (0.295", 7.50mm Width) |
Key Features
- Accurate RMS-to-DC conversion for complex waveforms, providing a true representation of the signal's power.
- Wide dynamic range of 60 dB, allowing for the measurement of a broad range of signal levels.
- Operates from a single or dual polarity power supply (±3V to ±18V), offering versatility in application.[
- Low supply current of 2.2 mA, making it energy-efficient for various applications.[
- Flat frequency response from DC to 1 MHz, ensuring accurate measurements across a wide frequency range.[
- Excellent temperature stability, with versions available for different temperature ranges (Grade J, A/B, S).[
- Internal trimming for offset and scale factor, ensuring high accuracy without the need for external adjustments.[
- On-chip buffer amplifier that can be used as an input buffer or in an active filter configuration to reduce AC ripple and increase accuracy.[
- Chip select feature to reduce supply current to 350 µA when the RMS function is not in use, suitable for remote or handheld applications.[
Applications
- Power monitoring and measurement.[
- Audio and video equipment.[
- Industrial instrumentation and control systems.[
- Medical equipment.[
- Test and measurement devices.[
- Industrial production.[
- Smart home appliances.[
- Electric vehicles.[
- Internet of Things (IoT) devices.[
Q & A
- What is the primary function of the AD637JR?
The AD637JR is a high-precision RMS-to-DC converter that computes the true RMS value of any complex waveform.
- What is the operating voltage range of the AD637JR?
The AD637JR operates from a single or dual polarity power supply ranging from ±3V to ±18V.[
- What is the dynamic range of the AD637JR?
The dynamic range of the AD637JR is 60 dB.[
- What are the temperature ranges for different grades of the AD637JR?
The AD637JR is available in Grade J (0°C to 70°C), Grade A/B (−40°C to +85°C), and Grade S (−55°C to +125°C).[
- How does the chip select feature work?
The chip select feature allows the supply current to be reduced to 350 µA when the RMS function is not in use, which is beneficial for remote or handheld applications.[
- What is the purpose of the on-chip buffer amplifier?
The on-chip buffer amplifier can be used either as an input buffer or in an active filter configuration to reduce AC ripple and increase accuracy.[
- Is the AD637JR still in production?
No, the AD637JR is an obsolete product, but there are alternative models available such as the AD636 and AD737 series.[
- What are some common applications of the AD637JR?
Common applications include power monitoring, audio/video equipment, industrial instrumentation, medical equipment, and test and measurement devices.[
- How does the AD637JR handle input signals when supply voltages are lost?
The input circuitry of the AD637JR is protected from overload voltages in excess of the supply levels, and the inputs are not damaged by input signals if the supply voltages are lost.[
- What external component is required for the AD637JR?
The only external component required is a capacitor that sets the averaging period, which also determines low frequency accuracy, ripple level, and settling time.[
