TL061

Description

The TL061 is the single-channel version of the TL062. Like the rest of the “TL06x” family, it is specifically optimized for low power consumption while retaining the signature high input impedance of the JFET input stage.

Because it is a single-channel device, it includes the offset nulling capability that is missing in the dual (TL062) and quad (TL064) packages, allowing for precision DC calibration.

Key Specifications

• Architecture: Single Op-Amp (8-pin package).

• Supply Current: Extremely low, typically $200 \, \mu\text{A}$ per amplifier.

• Input Impedance: $10^{12} \, \Omega$.

• Slew Rate: $3.5 \, \text{V}/\mu\text{s}$.

• Unity Gain Bandwidth: $1 \, \text{MHz}$.

The Role of Offset Nulling

Since the TL061 is a single op-amp, pins 1 and 5 are dedicated to Offset Null. In sensitive DC applications, the internal input transistors may not be perfectly matched, resulting in a small “offset voltage” at the output even when the inputs are at the same potential.

• You can connect a $10 \, \text{k}\Omega$ to $100 \, \text{k}\Omega$ potentiometer between these pins and the negative rail to manually “zero out” this error.

TL06x Series Quick Comparison

When to use the TL061?

1. Precision Battery-Powered Sensors: If you are building a single-stage sensor interface (like a pH sensor or a light meter) that must run for months on a battery, the TL061 is ideal.

2. DC Precision: When you need the high impedance of a JFET input but also require the ability to trim the output voltage to exactly zero.

3. Space and Routing: If your PCB layout has one sensor located far away from others, placing a single TL061 near the signal source is often cleaner than running long, sensitive traces to a dual or quad op-amp.

A Note on Performance:

Remember that the entire TL06x family prioritizes “low power” over “speed.” If your project involves high-frequency signals or high-fidelity audio, you should switch to the TL071 (low noise/high speed). If your project is a slow-moving DC or low-frequency measurement, the TL061 will save you significant battery life.