10M45 Mu-Stage Idea?

[Ryssen]

An old thread,well not so old.😉
But how to calculate the current giving resistor that 10M45S use?
Don´t know what volt to calculate on.

 

[Audio_idiot]

hi
There isn't any calculation, just a graph to determine your required current. As for voltage, as long as you don't burn the chip by exceeding 450V, they will servive.

Hope this help.

Cheers

 

[mach1]

But how to calculate the current giving resistor that 10M45S use?

The graph on the datasheet is only approximate: 10M45S are not consistent, and the resistance required to set a given current varies between each device.

Set up a test circuit with a pot to set the current and a series wired voltage dropping resistor, then dial in the current you need by measuring the Voltage drop across the resistor.

pm

 

[sgerus]

Tested
1500R=2.11mA
1650R=1.83mA
2000R=1.60mA
2300R=1.40mA
3000R=1.12mA
3400R=1.00mA

Estimate From Graph
1000R=3mA
800R=4mA
600R=5mA
300R=9mA
270R=10mA
150R=20mA
100R=26mA

I use a 4.7K R from G to the output end of the current setting resistor.

 

[Ryssen]

Wow!
So if Iwant say 30-40mA I can use a 100 ohm resistor paralleld with a trimpotentiometer,maybee 5Kohm?