Help in reduce circuit losses

[GH Crash]

Any suggestions on how to reduce the resistance of the attached circuit.

A supercapacitor (EDLC) is used to power a small motor. There is an ATTiny85 chip in the circuit that is used as a timer and a PWM controller for the motor. The problem that I'm loosing about half a volt between the capacitor's voltage and the voltage across the motor's leads. I need to minimize losses in the circuit as much as possible.

Can you suggest means to reduce voltage loses to the motor?

 

[Nigel Goodwin]

For those of you who question the use of a capacitor, the entire driving force behind this project is to make a device/circuit that will make a capacitor preform like a battery. Why? Because no one has done it.

There are good reasons for that, a capacitor makes a pretty poor battery.

 

[GH Crash]

So where do you measure V loo\sr and how much is the loss in V ?

Ok, you lost the dummy again. "Measure V loo\sr" ??? Capacitor voltage is measured across the cap leads, motor voltage is across the motor leads. The difference between the two is about half a volt.

 

[GH Crash]

There are good reasons for that, a capacitor makes a pretty poor battery.

Under some/most conditions, I agree with you, but in other cases, a battery makes a pretty poor power supply. As a free flight power source, batteries are heavy and take time to recharge. Capacitor are much lighter and re-charge within seconds.

 

[AnalogKid]

For those of you who question the use of a capacitor, the entire driving force behind this project is to make a device/circuit that will make a capacitor preform like a battery. Why? Because no one has done it.

Actually, lotsa people have done it. Ultracaps are common on hybrid city busses, and Coleman (the camping lantern people) used to make a cordless screw driver that used caps instead of nicad cells.

ak

 

[Nigel Goodwin]

Under some/most conditions, I agree with you, but in other cases, a battery makes a pretty poor power supply. As a free flight power source, batteries are heavy and take time to recharge. Capacitor are much lighter and re-charge within seconds.

They are lighter, and charge faster, mostly because they are much lower capacity - and to charge quickly requires large charging currents. It's simple physics - to charge faster needs higher current - to put hours of charge in a storage medium in seconds takes massive currents. For example, if a battery takes 5 hours to charge at 1A, a similar specification (if such existed) capacitor would need 60A to charge in 5 minutes, or 300A to charge in just one minute.

 

[alec_t]

The difference between the two is about half a volt.

You shouldn't be losing 1/2 Volt if the current is 3A. There must be a poor connection or else the wire cross-section is too small.

 

[danadak]

Ok, you lost the dummy again. "Measure V loo\sr" ??? Capacitor voltage is measured across the cap leads, motor voltage is across the motor leads. The difference between the two is about half a volt.

Meaure Voltage loss, where the drops occur, what path element creates the loss ?