Cr-Led Test Function - ITech IT8700P+ Series User Manual

4.14 CR-LED Test Function

With adding of diode break-over voltage setting in the IT8700 series electronic
load under conventional CR mode, the electronic load only works when voltage
applied at its both ends is higher than the diode break-over voltage to give a
real simulation of diode working principle, i.e., the ripple current at real LED
test.
The I-V curve of LED is as shown below. Under conventional CR mode, the
electronic load only simulates the static working point of diode as shown in the
red circle of the following figure. It is unable to verify the dynamic characteristics
of LED under normal working conditions, and the status of accurate ripple
current.
The definitions of parameters shown in the above figure are as follows:

Vo: constant working voltage of load LED of LED constant current source;

Io: output current of LED constant current source;

Vd: break-over voltage of diode (string);

R: constant resistance.
Setting CR-LED Mode
1. Power on the electronic load.
2. Select the channel.
3. Press
Sync On Set
4. Press
On
Off（Default）
5. Press
6. Press
MODE=
7. Press
key to select the mode CR, press
Const Current
Const Voltage
>Const Resis.
8. Press
resistance.
Const Resis.
Set=7500.0
5 5
Shift Shift
+ to enter configuration menu
▼ ▼
key to move to CR-LED. Press
Esc Esc
key to exit.
Setup Setup
key to enter the setup menu.
CC
Enter Enter
key to enter the mode selection menu <Mode>, press
▼ ▼
key to move to Rset=7500.0. You need to set the constant
Copyright © Itech Electronic Co., Ltd.
Operations introduction
Enter Enter
key to confirm.
Enter
key to confirm.
▼ ▼
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