Microchip Technology TO263-3EV-VREG 사용자 설명서

DS51818A-page 8

© 2009 Microchip Technology Inc.

8. Read the Ground Current directly from the ammeter connected to testpoints TP6 

and TP7.

9. Vary the input voltage to obtain data for ground current versus input voltage.  

With no load attached to the output of the voltage regulator, the measured ground 
current is also called the quiescent current of the regulator.

10. Add a load selection jumper, JP4 or JP5. 
11. Read the Ground Current directly from the ammeter connected to testpoints TP6 

and TP7.

12.  The data collected will be the ground current versus load current.

R

5

 and R

6

 are used to set desired load values. One choice is to set R

5

 to the minimum 

current desired for testing. R

6

 would then be set to a value desired for specific tests.  

Either value may be selected by adding their respective jumpers.

Dynamic Line Step response may be evaluated by connecting an electronically 
switched input voltage to testpoints TP1(+) and TP2(-) or to connector J1. An 
oscilloscope is connected to TP3(Ch1 Trigger), TP9(Ch2) and TP10(Gnd). An 
appropriate load is selected using R

5

 and JP4 or R

6

 and JP5. The input voltage is then 

electronically switched from a low voltage to a high voltage. The corresponding voltage 
waveform data of the voltage regulator response is captured by the oscilloscope.  
Microchip will be offering a Line Step module that connects directly to connector J1. 
The Line Step module will be capable of switching between two voltage levels that the 
user supplies.

Dynamic Load Step response may be evaluated by connecting an electronically 
switched load to testpoints TP9(+) and TP10(-) or to connector P1. An oscilloscope is 
connected to the electronic load switch signal (Ch1 Trigger) and to TP9(Ch2) and 
TP10(Gnd). The load is then electronically switched from a high resistance to a low 
resistance. The corresponding voltage waveform data of the voltage regulator 
response is captured by the oscilloscope. Microchip will be offering a Load Step module 
that connects directly to connector P1. The Load Step module will have several 
selectable load values populated onboard to cover a wide range of loads. The load will 
have the ability to be electronically or manually switched.

Power Supply Rejection Ratio tests are performed by removing the input capacitor 
jumper, JP1, and connecting an appropriate PSRR analyzer to the TO220-3/TO263-3 
Voltage Regulator Evaluation Board. The PSRR analyzer may then sweep the input 
voltage frequencies and record the corresponding output voltages.