Oki Dr.63514, User Manual, Page: 64 / 101

Chapter 2. Functions
2-43
2.14 Operating power supply selection function
Except for port 8 and the monitor pins, the voltage on all pins in the user cable and all signal in the
probes depend on this operating power supply setting.
•
emulator internal power supply (1.5 V)
•
external power supply (power is taken from the USR.VDD pin in the user cable)
Operating power supply selection function: Except for port 8 and the monitor pins, the voltage on all pins
in the user cable and all signal in the probes depend on this operating power supply setting.
USR.VDD
( User cable)
Protection
circuit
EXT
IN
Operating
power supply
(VDD)
VDD.SEL
switch
Internal
power supply
(1.5 V)
Figure 2-21 Operating power supply selection circuit
The VDD.SEL switch switches between internal and external power supply operation. When the
VDD.SEL switch is set to the IN position, the emulator internal power supply (1.5 V) is selected, and
when it is set to the EXT position, the external power supply operation is selected, i.e., power is taken
from the USR.VDD pin in the user cable. The user cable USR.VDD pin protection circuit is provided to
prevent internal damage to the emulator if the power-supply voltage is applied to the user cable
USR.VDD pin before the emulator power supply is turned on.
Caution
The USR.VDD input voltage must be between 0.9 and
5.5 V. Using a voltage outside this range risks
damaging the evaluation chip.