USR-WIFI232-D2 Hardware Manual
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2.Hardware Design
2.1. Typical Connection
Figure 3 Typical connection
1. nRST: Input pin. Resetting the module and taking effect in low level. nRST pin connect to internal 100K
Ohm pull-up resistor to 3.3V. Press over 300ms and release to reset the device.
2. nReady: Output pin. Output low level(or heartbeat signal) after module starting normally. nReady pin
connect to internal 4.7K Ohm pull-up resistor to 3.3V.
3. nLink: Output pin. Output low level when module connect to AP or has STA device connect to module in
AP mode. nLink pin connect to internal 4.7K Ohm pull-up resistor to 3.3V.
4. nReload: nReload pin can connect to external button or configuration pin. Press over 3s to restore default
settings. nReload pin should connect to external 4.7k-10k Ohm pull-up resistor.
2.2. Power Interface
USR-WIFI232-D2 adopt single-voltage 3.3 V power supply. Peak current is about 350mA, work current is
about 200mA and sleep mode current is 100mA.
The power filter is recommended to be used near the connector of the user board, and it is recommended to
use three parallel decoupling capacitors with 100uF, 10uF and 100nF to improve the stability of the system
and wireless performance.
