Overview
The AD736BR, produced by Analog Devices Inc., is a low power, precision, monolithic true rms-to-dc converter. This device is designed to convert ac voltage waveforms to dc voltages, providing true rms, average rectified, or absolute values. It is particularly suited for applications requiring high accuracy and low power consumption, making it ideal for battery-powered devices such as portable multimeters.
The AD736BR is laser trimmed to ensure a maximum error of ±0.3 mV ± 0.3% of reading with sine wave inputs. It maintains high accuracy across a wide range of input waveforms, including variable duty-cycle pulses and triac (phase)-controlled sine waves. The device operates with a wide power supply range of +2.8 V, −3.2 V to ±16.5 V and consumes only 200 μA of power supply current.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Input Range | 200 | mV rms (full-scale) | ||
| Input Impedance | 10^12 | Ω | ||
| Input Bias Current | 25 | pA | ||
| Accuracy | ±0.3 mV ± 0.3% | of reading | ||
| Crest Factor Range | 1 | 5 | ||
| Power Supply Range | +2.8 V, −3.2 V | ±16.5 V | V | |
| Supply Current | 200 | μA | ||
| Operating Temperature Range | −40°C | +85°C | °C | |
| Package Type | 8-SOIC |
Key Features
- Computes the true rms, average rectified, or absolute value of ac and dc input voltages.
- High input impedance of 10^12 Ω, eliminating the need for an external buffer with input attenuators.
- Low input bias current of 25 pA maximum.
- High accuracy with ±0.3 mV ± 0.3% of reading.
- RMS conversion with signal crest factors up to 5.
- Wide power supply range: +2.8 V, −3.2 V to ±16.5 V.
- Low power consumption: 200 μA maximum supply current.
- Buffered voltage output with no external trims needed for specified accuracy.
- Operates as an ac-coupled device with an external capacitor.
- Available in industrial temperature range: −40°C to +85°C.
Applications
- Portable multimeters and other battery-powered measurement instruments.
- Signal conditioning in various industrial and medical devices.
- Upgrading the performance of non-rms precision rectifiers in existing circuits.
- Measurement of ac and dc voltages in power monitoring and control systems.
Q & A
- What is the primary function of the AD736BR?
The AD736BR is a true rms-to-dc converter that converts ac voltage waveforms to dc voltages, providing true rms, average rectified, or absolute values.
- What is the input impedance of the AD736BR?
The input impedance of the AD736BR is 10^12 Ω.
- What is the maximum input bias current of the AD736BR?
The maximum input bias current is 25 pA.
- What is the accuracy of the AD736BR?
The accuracy is ±0.3 mV ± 0.3% of reading.
- What is the power supply range of the AD736BR?
The power supply range is +2.8 V, −3.2 V to ±16.5 V.
- How much power does the AD736BR consume?
The AD736BR consumes a maximum of 200 μA of power supply current.
- Does the AD736BR require external trims for accuracy?
No, the AD736BR does not require external trims for specified accuracy.
- Can the AD736BR operate as an ac-coupled device?
Yes, the AD736BR can operate as an ac-coupled device by adding one external capacitor.
- What are the typical applications of the AD736BR?
Typical applications include portable multimeters, signal conditioning in industrial and medical devices, and power monitoring systems.
- What is the operating temperature range of the AD736BR?
The operating temperature range is −40°C to +85°C.
