Digital Ammeter Circuit Using IC L7107

Ammeter could be an extremely useful inclusion to every Laboratory Power Supply set up as it assists to identify the current usage, and enables to assess whether there may be any hazardous current in the circuit that one may be constructing or experimenting with.
This ampere meter equipped to measure the ampere intake up to 10A with a selection range of 100mA, 10mA and 1mA accuracy, and itself works with a nominal 25mA of current.

The ammeter works using a single ICL7107 chip and 3.5-digit seven segment LED display module.

Owing to the fact that it employs quite a less quantity of components that the circuit is using it becomes feasible to enclose it on a minimal 3cm x 7cm printed circuit board.

The 0.01 Ohm resistor needs to sorted out of 1.5mm thick / 5cm stretched copper wire. 0.1 Ohm and the 1 Ohm resistors should be ensured with 5W ratings.


For maximum sensitivity may be remembered that the ICL7107 ampere meter module ought to be powered from its built-in voltage supply. If it's required that the readings of the ampere of the same supply felt necessary, ICL7107 ampere meter could be fed with a sample negative rather not a positive voltage supply.

The illuminating power of the LED module could be changed by including or excluding 1N4148 garden diodes that may be associated in series with the LED module inputs. You may want to utilize two 1N4148 diodes for an enhanced luminance.

Having said this, the incorporation 7805 5V voltage regulator is must be included without forgetting to restrict the damage or malfunction of ICL7107 and 7660 ICs.

The dot point on the seven segment LED display could be if required further displaced with the association of a dual switch as indicated below.

10A - 100mA Resolution - 99.9 A
5A - 10mA Resolution - 9.99 A
2A - 1mA Resolution - 1.999 A

There is the feature of using the 10K potentiometer to vary and set the affixed reference voltage between PIN 35 and PIN 36 of the ICL7107 IC to 1V.

Parts list for the above digital ammeter circuit


Resistors

0.01 Ohm - 1.5mm / 5cm long copper wire
0.1 Ohm - 5W
1 Ohm - 5W

1x - 220 Ohm
1x - 10K
1x - 15K
1x - 47K
1x - 100K
1x 10K Pot

Capacitors

1x - 100pF
1x - 10n
1x - 100n
1x - 220n
1x - 470n
2x - 10uF


Semiconductors


3x - 1N4148 Diode
1x - ICL7107 IC
1x - 7660 IC
2x - MAN6910 2-digit LED 7-segment Display

Technical Datasheet

Supply Voltage: 5V
Current Consumption: ~ 25mA

Measurement Accuracy:

 
10A - 100mA Resolution - 99.9 A
5A - 10mA Resolution - 9.99 A
2A - 1mA Resolution - 1.999 A