LPS Display

Version 1 by Stephane Carrez

Overview

Power Supply Control

  • Voltage
  • Current limitation
  • Supply ON/OFF
  • Ramp up time
  • Calibration voltage
  • Calibration current

Global Control

  • Fan speed

Interface

The LPS interface is composed of a 2x16 LCD display, a set of 5 buttons and 2 selection wheels.

  • Voltage (V)
  • Current (A)
  • Power (W)
  • Max, min, mean current
  • Max, min, mean voltage

Display on 2x16 LCD.

123456789ABCDEF

1 +12.00V 250mA 2 -11.85V 125mA

3 +5.034V 2.34A 4 -3.033V 1.12A

+12.00V -11.85V +5.034V -3.033V

1:12V 3:-12V 2:5.0V 4:-3.0V

rotateur 1 -> Voltage +/- rotateur 2 -> Current +/-

1 +12.00V 250mA I-Max 490mA

I-Min 125mA P-Max 2.34W

1 +12.00V 250mA I-Limit 800mA

Main View

The main view has several display modes that are selected by the right wheel.

Voltage Overview

The voltage overview gives a quick overview of the different output voltages currently selected for the power supplies.

Voltage and Current Display

The voltage and current or the voltage and output power can be displayed for two power supplies at the same time.

Fan Control

Temperature Control

Single Supply Display

This mode displays a single power supply. It allows to control and view all the details of the power supply.

Voltage and Maximum Current Control

This mode allows to select the power supply voltage and the maximum output current.

Voltage and Current Calibration

Calibration is necessary to increase the precision of the laboratory power supply. It is controlled by the ATmel microcontroller.

  • Voltage calibration is achieved by measuring the power supply voltage with a multimeter and entering the measured value in LPS.
  • Current calibration is achieved by measuring the output current while the output is under some load. The load has no importance.

The display is the following:

The left button is used to calibrate the voltage and the right button to calibrate the output current.