The ±5V Module

This module for the HS10X DIY Oscilloscopes allow to use HS oscilloscopes with the most common voltage range for electronic applications in signal analysis. This module allow to analise audio and low frequency signals from circuits or sensors.

1. Simple solution


Specifications
  • Input Range

    -5V to +5V

  • Bandwidth
    (sine wave -3dB)

    Not limited (sine wave visible with sinc interpolation up to 400KHz @ 1800KS/s)

  • Input Impedence

    5KΩ

  • Limitations

    When the probe is open this circuit show a voltage of around 2.4V. Just connect the probe to GND to have 0V or to the circuit under test to read the current voltage value.

2. Best DIY Solution

This solution is actually an effective, stable and accurate ±5V input stage, with (so far) the less number of components possible. So a best DIY solution.


Specifications
  • Max Input Range

    -5.4V to +5.4V (need calibration in HScope)

  • Bandwidth
    (sine wave -3dB)

    Not limited (sine wave visible with sinc interpolation up to 400KHz @ 1800KS/s)

  • Input Impedence

    10KΩ

  • Over Voltage Protection

    Tested up to ±25V


List of the components


Name Value
Perforated PCB Board 6x7 holes
Connectors 6 Pin single row female 2.54mm pin header connector strip (x2)
6 Pin single row male 2.54mm pin header connector strip (x2)
Resistors 4.7KΩ - 1/4W (x2), 5.1KΩ - 1/4W, 1KΩ - 1/4W  
C 100uF (voltage not relevant)  
D1 1N4007 (x2)  
IC ASM 11117 - 1.2V  

3. 1MΩ Solution

This solution provide high input impedence as standard market oscilloscopes. 1MΩ allow to use standard probes and to accurately measure signals from sources like sensors or other low impedence sources. Also the sampling rate 1.8MSa/s show no problems.


Specifications
  • Max Input Range

    -5.1V to +5.1V (need calibration in HScope)

  • Bandwidth
    (sine wave -3dB)

    Not limited (sine wave visible with sinc interpolation up to 400KHz @ 1800KS/s)

  • Input Impedence

    1MΩ

  • Over Voltage Protection

    Tested up to ±25V


List of the components


Name Value
Perforated PCB Board 9x7 holes
Connectors 6 Pin single row female 2.54mm pin header connector strip (x2)
6 Pin single row male 2.54mm pin header connector strip (x2)
Resistors 680KΩ - 1/4W, 330KΩ - 1/4W, 1KΩ - 1/4W  
C 100uF (x2, voltage not relevant), 22pF, 36pF  
D1 1N4007 (x2)  
IC ASM 11117 - 1.2V, MCP6S21  

4. Tests

Tests on this module has been performed with the STM32 Black Pill board and the Best DIY Solution. Results shows high accuracy both in amplitude (after calibration) and in frequency.

Calibration has been done in HScope, first the zero level by connecting the probe to the probe GND, then the multiplier has been calibrated with reference voltage 5V from an indipendent 5V stable source (cannot be used any reference voltage from the STM32 board).

DC Accuracy has been tested comparing the results with the Victor 86E multimeter with accuracy of ±(0.05%+8d).

DC Tests


Victor 86EHS101 @ 100KSa/sHS101 noise
0 V< 1mV16mV @ 900KSa/s, 5mV @ 100KSa/s
4.985 V4.99 V8mV
3.320 V3.32 V8mV
-3.320 V-3.32 V5mV
-4.986 V-4.99 VNA






AC Tests


10Hz




100Hz




1KHz




10KHz




100KHz




200KHz, 300KHz, 400KHz, 500KHz (using sinc interpolation)





5. Other

Schematic files are available on GitHub.

First Release: Jan 2019
Last Update: Apr 2019