Gophert NPS-160X Replacement User Interface
Gophert NPS-160X Replacement User Interface
This is a replacement front panel for the Gophert NPS-1600/1601/1602 power supplies with a better user interface,
better accuracy, and more features.
Features:
- 3.2" Color LCD with touch screen
- Jog dial (rotary encoder) with Velocirotor accelleration
- Output indicator LED
- Alternate display for watts instead of current
- Presets for voltage and current
- 3.3V, 5V, and 12V Safe Limits to prevent inadvertent overvoltage
- Voltage & current tracking for better accuracy
- Internal temperature
- Arduino software
- Teensy 3.2 microcontroller
Design Documents
| Schematic Diagram | gophert_schematic.pdf |
| 3D Print Files | gophert_mechanical.zip |
| Source Code - Arduino | Arduino.zip |
The Gophert NPS-1600/1601/1602 power supplies are an excellent value; they have good voltage and current regulation plus low noise. However the user interface is not very good.
Fortunately the power supply and user interface sections are separate. The front panel is connected by a JST cable so it can be easily replaced. Also fortunately the three models use the same connector pinout and similar control signals for voltage and current control.
The microcontroller sets the voltage and current outputs with two PWM signals. The PWM is filtered and buffered to make a nice stable control voltage. A calibration procedure establishes the control signal levels for volts and amps. These levels vary from model to model. The output voltage is initially set from the calibrated values, then the output voltage is monitored and actively tracks the set voltage.
Teensy was chosen primarily because of the display library support, which makes programming the large font characters and graphics pretty easy.
Build Pictures
Breadboard Testing
Circuit Board Assembly
Some of the screens
