Unitech ES922, Руководство пользователя

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7
2-3 Typical input/output, LDO external, and DC/DC circuitries
Input: each input IO pin is internally pulled up
by a 100K Ohm resistor (VCC=3.3V).
Min. Max.
V
inL
-0.3V 0.7V
V
inH
2.4V 3.6V
100K
V C C
E m bedded
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IN P U T
Output: each output port is an open-drain pad
with a 100K Ohm pull-up resistor and the
maximum sink current is 100 mA (VCC=3.3V).
100K
V C C
E m bedded
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O U T P U T
External LDO circuitry: it is recommended to
apply low noise LDO (Low Dropout Voltage)
regulators.
LD O
R egulator
E m bedded
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22 u
External switching regulator circuitry:
Min. Max.
Switching Frequency 1 MHz -
Ripple V
P-P
- 50 mV
S w itching
R egulator
E m bedded
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22 u