PicoScope 7 Software
Available on Windows, Mac and Linux
PicoScope 7 Software
Available on Windows, Mac and Linux
OEM & custom applications
PicoScope, Pico data logger and RF products can be used as components in custom applications and OEM projects.
A to Z of PC oscilloscopes
Everything you need to know about PC oscilloscopes from Advanced Triggers to Zooming.
A to Z of Data Loggers
Everything you need to know about PC-based data loggers from Alarms to Zooming.
Application Notes
Details of some of the many applications for Pico data logger and oscilloscope products.
How do I measure...?
Find out how you can measure using Pico products
Videos
Showing you how to get the most out of PicoScope oscilloscope software.
Documentation
Up-to-date versions of the documentation supplied with your products in PDF format.
Educational Experiments
Our library of science experiments suitable for use with oscilloscope and data logging products.
PicoApps
Want to share hints, tips and code with other developers? Show your Pico-based products to the world.
Newsletter
Archive of our monthly Test and Measurement Newsletters.
THE RATIOMETRIC PROBLEM
Because of the ratiometric nature of the sensor, variations in the supply voltage of the sensor introduce a reading error as follows.
Supply...........Offset...........Error............Corrected & Linearised Error
V..................mV..............Litres............Litres
5,5................220..............7,74..............7,7
5,4................216..............6,02..............6,2
5,3................213..............4,73..............4,6
5,2................209..............3,01..............3,1
5,1................206..............1,72..............1,6
5..................202...............0,00..............0,1
4,9................199..............-1,29............-1,4
4,8................195..............-3,01............-3,0
4,7................192..............-4,3.............-4,5
4,6................188..............-6,02............-6,0
4,5................184..............-7,74............-7,5
Considering that the USB + 5V can vary in the range 4.75 to 5.25 V, We could have a random reading error in excess of +/- 3 litres, which might not be acceptable in some instances. The solution is to use a precision + 5 V supply to feed the sensor, which needs approx. 6 mA. To do this the jumper between pins 11 & 12 of M1 (DrDAQ Buffer) must be removed and the stable + 5 V applied to Pin 12.