Overview
The LF412CN/NOPB is a low offset, low drift dual JFET input operational amplifier produced by Texas Instruments. This device is part of the BI-FET II™ series, known for its very low input offset voltages and high input impedance. The LF412CN/NOPB is designed to operate with high slew rates and wide bandwidth, making it suitable for a variety of high-performance applications.
Key Specifications
| Parameter | Value | Conditions |
|---|---|---|
| Input Offset Voltage | 0.5 mV (Typ), 2 mV (Max) | VS = ±15V, TA = 25°C |
| Input Offset Voltage Drift | 7 µV/°C (Typ) | |
| Input Bias Current | 50 pA (Typ), 200 pA (Max) | VS = ±15V, TA = 25°C |
| Supply Voltage Range | ±5V to ±20V | |
| Operating Temperature Range | 0°C to 70°C (Commercial), -55°C to 125°C (Military) | |
| Slew Rate | 15 V/µs (Typ) | VS = ±15V |
| Bandwidth | 4 MHz (Typ) | VS = ±15V |
| Power Dissipation | 670 mW (Max) | |
| Lead Temperature (Soldering, 10 sec.) | 260°C |
Key Features
- Very low input offset voltage and drift.
- High input impedance due to JFET inputs.
- High slew rate of 15 V/µs.
- Wide bandwidth of 4 MHz.
- Low input bias current.
- Internally trimmed for low offset voltage (BI-FET II™ technology).
- Operates with a common-mode input voltage range that is independent of the supply voltages.
- Can drive a 2 kΩ load resistance to ±10V over the full temperature range.
Applications
The LF412CN/NOPB is suitable for various high-performance applications, including:
- High-speed integrators.
- Fast D/A converters.
- Sample and hold circuits.
- Other circuits requiring low input offset voltage and drift, low input bias current, high input impedance, high slew rate, and wide bandwidth.
Q & A
- What is the typical input offset voltage of the LF412CN/NOPB?
The typical input offset voltage is 0.5 mV.
- What is the input offset voltage drift of the LF412CN/NOPB?
The input offset voltage drift is 7 µV/°C (Typ).
- What is the operating temperature range for the commercial version of the LF412CN/NOPB?
The operating temperature range for the commercial version is 0°C to 70°C.
- What is the slew rate of the LF412CN/NOPB?
The slew rate is 15 V/µs (Typ).
- What is the bandwidth of the LF412CN/NOPB?
The bandwidth is 4 MHz (Typ).
- Can the LF412CN/NOPB drive heavy load currents?
The amplifier can drive a 2 kΩ load resistance to ±10V over the full temperature range. However, driving heavier load currents may increase the input offset voltage.
- What precautions should be taken during the layout of the LF412CN/NOPB?
Precautions include proper lead dress, component placement, and supply decoupling to ensure stability. Resistors from the output to an input should be placed close to the input to minimize pick-up.
- What is the minimum power supply voltage for the LF412CN/NOPB?
The minimum power supply voltage is ±5V.
- How should the power supplies be decoupled for the LF412CN/NOPB?
It is suggested to use 0.1µF capacitors placed as close as possible to the op amp power pins for decoupling the supply lines.
- What happens if the negative common-mode limit is exceeded on either input of the LF412CN/NOPB?
Exceeding the negative common-mode limit on either input will cause a reversal of the phase to the output and force the output to a high state.
