Renesas M-Station, Руководство пользователя

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M-Station Baseboard
3.4 JP3 V
DD
Voltage Generation
The V
DD
for biasing MCU devices can be adjusted to a desired voltage level. To set the desired V
DD
,
select JP3 for the preset voltage level. R10 is an optional footprint for through-hole resistor. If V
DD
other than the preset values is desired, install R10 to adjust V
DD
, and do not insert a jumper in JP3. To
calculate the desired V
DD
, use the following equation.
V
DD
_SEL = [1+(R1/R2)]*1.25 + (50µA)*R2
Where R1 = 825
Ω
/ R10 and R2 = 500
Ω
.
When there is no jumper inserted on JP3, V
DD
defaults to 2V to prevent V
DD
from rising to a high
voltage if you accidentally remove JP3 while power is connected. However, it is good practice to
remove power from J8 (power jack) before changing JP3, JP4, or any other jumpers.
Figure 5. JP3 Multiple V
DD
Generation
3.5 JP1 V
DE
Target Voltage Detect Bypass
When the M-Station baseboard is used for flash programming of a micro-board or target system, the
V
DE
signal (pin 10 on the flash programming connector) is used to sense that power is applied on the
micro-board or target system. V
DE
is also used to power the interface circuit between the M-Station
and micro-board to ensure compatible voltage levels.
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