Changes

===Using a DC Power Supply===

===Using a DC Power Supply===

With all voltage and current knobs set to minimum, turn on the power supply. If you need a very specific voltage, you may also connect the digital multimeter to the output of the DC power supply to give you a more accurate reading of the voltage. If your current knob is at the minimum, you may notice that nothing happens when you increase the voltage knob and a red LED turns on. This is because the current knob on a DC power supply operates as a current limiting function. At the minimum, the current knob will allow zero amps to flow, which means that the DC power supply will not provide any voltage. The purpose of the current limiter is to protect your circuit from damage. For example, if you know that your 100Ω resistor is rated at 0.25W, you might set your current limiter such that not more than 50mA will flow through that particular resistor to avoid burning it out (letting out the magic smoke).

With all voltage and current knobs set to minimum, turn on the power supply. If you need a very specific voltage, you may also connect the digital multimeter to the output of the DC power supply to give you a more accurate reading of the voltage. If your current knob is at the minimum, you may notice that nothing happens when you increase the voltage knob and a red LED turns on. This is because the current knob on a DC power supply operates as a current limiter. At the minimum, the current knob will allow zero amps to flow, which means that the DC power supply will not provide any voltage. The purpose of the current limiter is to protect your circuit from damage. For example, if you know that your 100Ω resistor is rated at 0.25W, you might set your current limiter such that not more than 50mA will flow through that particular resistor to avoid burning it up (letting out the magic smoke).

If you’ve done your calculations, you may not need to be as cautious with the current limiter, but it’s always a good idea to start low with the current limiter every time you are powering an untested circuit. Rarely will an insufficient current or voltage ever cause damage to analog or digital circuits. Granted, the circuit probably won’t function as expected with insufficient current/voltage, but it should be fine to slowly increase the current/voltage to the desired amount when you are first setting your DC power.

If you’ve done your calculations, you may not need to be as cautious with the current limiter, but it’s always a good idea to start low with the current limiter every time you are powering an untested circuit. Rarely will an insufficient current or voltage ever cause damage to analog or digital circuits. Granted, the circuit probably won’t function as expected with insufficient current/voltage, but it should be fine to slowly increase the current/voltage to the desired amount when you are first setting your DC power.