Renesas IE850A, Руководство пользователя

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E2, IE850A 2. Connecting the Emulator and User System
R20UT4140EJ0300 Rev.3.00 Page 14 of 41
Oct.09.20
2.3.5 Connecting the TVDD pin
(1) Power source monitoring function
Be sure to connect the power source for the power domain of the debug interface (JP0 port group) to pin 8
(TVDD pin) of the 14-pin connector.
The power source connected to the TVDD pin provides power to the final stage output buffer and first
stage input buffer on the E2 emulator circuit. When the E2 emulator is connected, it will draw current as
described below in addition to the current drawn by the user system.
•
Approx. 20 mA when TVDD is 3.3 V, and approx. 40 mA when TVDD is 5.0 V
If there is a possibility you will be using hot plug-in connection, be sure to refer to section 2.3.6, Hot plug-in
connection.
(2) Power supply function
The E2 emulator can also supply power at 3.3 V or 5.0 V from the TVDD pin to the user system (at a
current of up to 200 mA). When using this function, take care of the following points.

Do not use this function if power is being separately supplied to the user system. Attempting to do so
might break the E2 emulator.

Do not use this function for a user system which draws a current of 200 mA or more. The E2
emulator or USB interface of the host machine might be broken.

Make sure that the supplied voltage is within the voltage range required by the user system.
 If 5.0 V is supplied, the voltage might be lower than 5.0 V by 0.3 V or more depending on the
environment of the host machine that is in use.
For power supply from the E2 emulator, precision is not guaranteed. When writing a program that requires
reliability, do not use the power supply function of the E2 emulator. Use a stable, separate power supply for the
user system. When writing a program for mass production processes, use the Renesas Flash Programmer.
CAUTION
Turning the Power On/Off:
When supplying power, ensure that there are no shorts between the user system and power circuit.
Only connect the E2 after confirming that there are no mismatches of alignment on the user system
port connector. Incorrect connection will result in the host machine, the emulator, and the user
system emitting smoke or catching fire.