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What is output voltage trimming?
Trimming the output voltage of a power supply simply means adjusting the voltage by a small amount. By convention, the term trimming is used for applications where the power supply has a specified nominal output voltage and the user is able to change the output voltage by about ten percent or less.
What is trimming circuit?
Definition. Laser trimming is the manufacturing process of using a laser to adjust the operating parameters of an electronic circuit. One of the most common applications uses a laser to burn away small portions of resistors, raising their resistance value.
What is analog trimming?
A trimming operation compensates for variations in the analog circuits and sensors due to manufacturing variances of these components. Examples where trimming is used include automotive and industrial sensors, display controllers, and power management circuits.
What does a trimmer resistor do?
A trimmer potentiometer, also known as a trim pot, is a type of variable resistor or adjustable potentiometer that can adjust, tune, and calibrate circuits. These trimmer resistors are often used to initially calibrate equipment after manufacturing.
How can you trim the output voltage of a power supply?
Most often users are able to trim the output voltage of a power supply by adding external components, adjusting a PCB mounted potentiometer, or applying an analog or digital signal. Power supplies with the ability to trim the output voltage are typically used for two reasons:
How much voltage do you need for a limiting circuit?
Generally your current limiting circuit will require a bit of voltage “headroom” to operate in. That means you’ll need an unregulated PSU of > 5 V and regulate it down to 5 V while monitoring the current.
What happens if you try to reduce voltage?
The Ohm’s Law police will come after you if you attempt to regulate both voltage and current into a fixed load. Unless you have a very unusual load, the load will draw whatever current it needs if you supply the correct voltage. Any attempt to reduce the current will reduce the applied voltage.
How does a 0V Trimmer work on an amplifier?
It also has a trimmer over one of the op-amps’ offset for adjusting the 0V point of the output². Right now, when the device changes to a current regime and turns off the output, I’m seeing an output of a little more than negative 0.5V, which could be potentially damaging to an attached DUT.