Beefing up power supply with current source?

[MrPerfectionest]

I work for a semiconductor firm using a certain test machine to test
certain devices. We are starting to run up against the power
limitations of the power supplies of the tester, and are looking for
alternate ways to beef them up.

It has been awhile since I have had any real EE courses, so I can't
comprehend if this concept presented by another engineer will work.

The power supplies for the can adjust the voltage and clamp the
current. At the moment, because the product description is a little
ambiguous (and because it varies from product family to product
family), it's hard for us to say whether the supply can only source
current, or if it can sink current to. Maybe it doesn't matter.

Let's assume the power supply of the machine can supply at most 500mA
in a range from 1-5V. We have devices that under certain test
conditions will draw 30mA, and soon, under certain conditions will be
wanting to draw more than 500mA.

The idea is to stick a "current source" down stream of the tester
supply near to the device on the load board to supply the extra power
for when the part needs it. When the part isn't needing it, the tester
power supply will sink the current provided by the current source?

Does this make any sense?

 

[Eeyore]

I work for a semiconductor firm using a certain test machine to test
certain devices. We are starting to run up against the power
limitations of the power supplies of the tester, and are looking for
alternate ways to beef them up.

It has been awhile since I have had any real EE courses, so I can't
comprehend if this concept presented by another engineer will work.

The power supplies for the can adjust the voltage and clamp the
current. At the moment, because the product description is a little
ambiguous (and because it varies from product family to product
family), it's hard for us to say whether the supply can only source
current, or if it can sink current to. Maybe it doesn't matter.

Let's assume the power supply of the machine can supply at most 500mA
in a range from 1-5V. We have devices that under certain test
conditions will draw 30mA, and soon, under certain conditions will be
wanting to draw more than 500mA.

The idea is to stick a "current source" down stream of the tester
supply near to the device on the load board to supply the extra power
for when the part needs it. When the part isn't needing it, the tester
power supply will sink the current provided by the current source?

Does this make any sense?

It could work.

Does the tester have equal current sink and source capability ?

Graham

 

[Ancient_Hacker]

I work for a semiconductor firm using a certain test machine to test
certain devices. We are starting to run up against the power
limitations of the power supplies of the tester, and are looking for
alternate ways to beef them up.

It has been awhile since I have had any real EE courses, so I can't
comprehend if this concept presented by another engineer will work.

The power supplies for the can adjust the voltage and clamp the
current. At the moment, because the product description is a little
ambiguous (and because it varies from product family to product
family), it's hard for us to say whether the supply can only source
current, or if it can sink current to. Maybe it doesn't matter.

Let's assume the power supply of the machine can supply at most 500mA
in a range from 1-5V. We have devices that under certain test
conditions will draw 30mA, and soon, under certain conditions will be
wanting to draw more than 500mA.

The idea is to stick a "current source" down stream of the tester
supply near to the device on the load board to supply the extra power
for when the part needs it. When the part isn't needing it, the tester
power supply will sink the current provided by the current source?

Does this make any sense?

Not a lot of sense. If the source can't sink current, the idea won't
work. So you better figure that out right quick.

Also if the source can't supply 500ma, and it can sink current,
it's unlikely it will be able to sink 500-30mA if it can't source 500mA

How about you snip the wire and insert a current-booster? A
high-current op-amp as a voltage follower will do the trick.