Overview
The OPA445ADDAR is a high-voltage FET-input operational amplifier produced by Texas Instruments. This monolithic operational amplifier is designed to operate from power supplies up to ±45V and can deliver output currents of up to 15mA. It is particularly useful in applications requiring high output voltage or large common-mode voltage swings. The OPA445 features a high slew rate of 15V/µs, which provides a wide power-bandwidth response, making it suitable for high-voltage applications. The FET input circuitry allows the use of high-impedance feedback networks, minimizing their output loading effects. The device is available in various packages, including TO-99, DIP-8, SO-8 surface-mount, and SO-8 PowerPAD, which enhances thermal dissipation capabilities.
Key Specifications
| Parameter | Test Conditions | Min | Typ | Max | Units |
|---|---|---|---|---|---|
| Input Offset Voltage (VOS) | VCM = 0, IO = 0 | ±1 | ±3 | ±5 | mV |
| Input Bias Current (IB) | VCM = 0V | ±10 | ±50 | ±100 | pA |
| Common-Mode Voltage Range (VCM) | VS = ±40V | (V−) + 5 | (V+) - 5 | V | |
| Open-Loop Voltage Gain (AOL) | VO = −35V to +35V | 100 | 110 | dB | |
| Gain Bandwidth Product (GBW) | 2 | MHz | |||
| Slew Rate (SR) | VO = 70VPP | 5 | 15 | V/µs | |
| Operating Temperature Range | −55 | +125 | °C | ||
| Power Supply Range | ±10 | ±45 | V | ||
| Quiescent Current (IQ) | IO = 0 | ±4.2 | ±4.7 | mA |
Key Features
- High Voltage Operation: The OPA445 can operate from power supplies up to ±45V, making it suitable for high-voltage applications.
- High Slew Rate: A slew rate of 15V/µs provides a wide power-bandwidth response.
- Low Input Bias Current: Input bias current is as low as 10pA, which is beneficial for high-impedance feedback networks.
- Low Input Offset Voltage: Laser trimming of the input circuitry results in low input offset voltage and drift.
- Thermal Management: The SO-8 PowerPAD package enhances thermal dissipation capabilities, reducing the need for bulky heatsinks.
- Flexible Packaging: Available in TO-99, DIP-8, SO-8 surface-mount, and SO-8 PowerPAD packages.
Applications
- Test Equipment: Suitable for various test and measurement applications due to its high accuracy and stability.
- High-Voltage Regulators: Can be used in high-voltage regulator circuits requiring precise control.
- Power Amplifiers: Ideal for power amplifier applications where high output voltage and current are required.
- Data Acquisition and Signal Conditioning: Used in data acquisition systems and signal conditioning circuits due to its high input impedance and low noise.
- Audio and Piezo Drivers: Suitable for audio amplification and piezo driver applications requiring high voltage swings.
Q & A
- What is the maximum power supply voltage for the OPA445?
The OPA445 can operate from power supplies up to ±45V, or a total of 90V.
- What is the slew rate of the OPA445?
The slew rate of the OPA445 is 15V/µs.
- What is the input bias current of the OPA445?
The input bias current is as low as 10pA.
- What are the available packages for the OPA445?
The OPA445 is available in TO-99, DIP-8, SO-8 surface-mount, and SO-8 PowerPAD packages.
- How does the SO-8 PowerPAD package enhance thermal dissipation?
The SO-8 PowerPAD package has an exposed leadframe on the bottom that can be soldered directly to the PCB, significantly enhancing thermal dissipation capabilities.
- What is the maximum output current of the OPA445?
The OPA445 can supply output currents of up to 15mA.
- How can the output current be increased beyond 15mA?
The output current can be increased by connecting two or more OPA445s in parallel, with one configured as a master amplifier and the others as unity gain buffers.
- What is the operating temperature range of the OPA445?
The operating temperature range is from −55°C to +125°C.
- How can the offset voltage be adjusted in the OPA445?
The offset voltage can be adjusted using the offset voltage trim connections on pins 1 and 5 with a potentiometer.
- What precautions should be taken when handling the OPA445?
The OPA445 is susceptible to ESD damage, so proper handling and installation procedures must be followed to prevent damage).
