LF444CN Quad Low Power Operational Amplifier

Overview

The LF444CN is a quad low-power operational amplifier designed to deliver superior DC characteristics while maintaining the AC performance of the industry-standard LM148. This amplifier is optimized for applications requiring low power dissipation without compromising electrical performance. The LF444CN offers the same bandwidth, slew rate, and gain (with a 10 kΩ load) as the LM148 but consumes only one-fourth of the supply current. Additionally, its precision-matched high-voltage JFET input stage significantly reduces input bias and offset currents by a factor of 10,000 compared to the LM148. The LF444CN is pin-compatible with the LM148, making it an easy drop-in replacement for power-sensitive designs.

Features

• Low Power Consumption: Draws only 200 µA per amplifier (max), which is 1/4 the supply current of the LM148.
• High Input Impedance: JFET input stage provides very low input bias and offset currents.
• Low Noise: Features a very low equivalent input noise voltage for a low-power amplifier.
• Pin Compatibility: Direct replacement for LM148, enabling immediate power savings in existing designs.
• Wide Bandwidth: Maintains the same bandwidth and slew rate as the LM148.
• Stable Performance: Excellent gain and phase margin for stability in feedback configurations.

Applications

The LF444CN is ideal for a wide range of low-power and precision analog applications, including:

• Portable and Battery-Powered Devices: Due to its low current consumption, it is well-suited for handheld instruments, medical devices, and remote sensors.
• Signal Conditioning: Used in active filters, integrators, and precision amplifiers where low noise and low power are critical.
• Data Acquisition Systems: Provides accurate amplification in multi-channel ADC and DAC interfaces.
• Audio Processing: Suitable for low-noise preamplifiers and tone control circuits.
• Industrial Control Systems: Reliable operation in process control and instrumentation amplifiers.

Electrical Characteristics

The following table summarizes the key electrical specifications of the LF444CN under typical operating conditions (V_CC = ±15V, T_A = 25°C unless otherwise noted).

DC Characteristics

• Supply Voltage Range: ±5V to ±18V
• Input Offset Voltage: 3 mV (max)
• Input Bias Current: 50 pA (max)
• Input Offset Current: 25 pA (max)
• Common Mode Rejection Ratio (CMRR): 90 dB (min)
• Supply Current (per amplifier): 200 µA (max)

AC Characteristics

• Gain Bandwidth Product: 1 MHz (typ)
• Slew Rate: 0.5 V/µs (typ)
• Equivalent Input Noise Voltage: 25 nV/√Hz (typ at 1 kHz)

Package Information

The LF444CN is available in a standard 14-pin PDIP (Plastic Dual In-line Package) with the following mechanical specifications:

• Package Type: PDIP-14
• Dimensions: 19.3 mm x 6.35 mm (0.76 in x 0.25 in)
• Pin Pitch: 2.54 mm (0.1 in)
• Operating Temperature Range: 0°C to 70°C
• Lead Material: Solder-plated copper

The pinout configuration is as follows:

• Pin 1: Output A
• Pin 2: Inverting Input A
• Pin 3: Non-Inverting Input A
• Pin 4: V_CC- (Negative Supply)
• Pin 5: Non-Inverting Input B
• Pin 6: Inverting Input B
• Pin 7: Output B
• Pin 8: Output C
• Pin 9: Inverting Input C
• Pin 10: Non-Inverting Input C
• Pin 11: V_CC+ (Positive Supply)
• Pin 12: Non-Inverting Input D
• Pin 13: Inverting Input D
• Pin 14: Output D

Conclusion

The LF444CN quad low-power operational amplifier is an excellent choice for designers seeking to reduce power consumption without sacrificing performance. Its combination of low supply current, high input impedance, and low noise makes it suitable for a variety of precision analog applications. With pin compatibility to the LM148, upgrading existing designs for improved efficiency is straightforward. Whether used in portable electronics, industrial systems, or audio processing, the LF444CN delivers reliable and efficient operation.