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===Collector Supply=== | ===Collector Supply=== | ||
The collector supply is a floating programmable power supply. | The collector supply is a floating programmable regulated power supply. | ||
The output voltage, output polarity, and series resistance are all | The control and data signals entering the collector supply are isolated by relays and optoisolators. | ||
The output voltage, output polarity, and series resistance are all set by bits sent by the 8048 processor. | |||
The collector supply is linear, | An Analog Devices DAC08 DAC, which is floating along with the rest of the collector supply, | ||
generates the programmable collector voltage. | |||
The digital DAC value sent by the microprocessor passes through optoisolators before being fed to the DAC. | |||
The collector supply is linear, basically a discrete power op-amp. | |||
The output stage is a Darlington configuration of three NPN transistors. | |||
When supplying 2 A to the DUT at 0.5V, the power dissipation in the collector supply output transistors | |||
is around 100 watts. | |||
In contrast, curve tracers that use rectified mains frequency from a transformer, e.g., the [[576]], | |||
dissipate very little internally even while supplying high current to the DUT. | |||
==Specifications== | ==Specifications== |