BLE2U5 http://wch.cn
15 AT I ATtransparenttransmission function switch pin:
Lowlevel:ATmode. High level:Transparenttransmission mode
16 RELOAD
/BLESTA I/O
Restore factorysetting inputpin (RELOAD)when powered on,
Restore the factorysettingsaftera lowlevelisdetected for2
secondscontinuously.
BLEconnection statusindication signaloutputpin (BLESTA)
afterpowered on. Itoutputslowlevelwhen notconnected, while it
outputshigh levelwhen connected.
17 FCE I CTS/RTS flowcontrolenable, active low, with built-in pull-up
resistor
18 DTR# O UARTMODEMoutputsignal, data terminalready
19 UD+ USBsignal
USBD+data line
20 UD- USBsignal
USBD-data line
21 TXD O UARTtransmit pin
22 RXD I UARTreceive pin
23 RST# I Resetpin, active low
24 TNOW O UARTtransmit statuspin, active high
Note (1): P:Power.A:Analog. I:Input. O:Output. N:Noconnection.
Note (2): Touse an externalantenna, the usercan connectthe PANTpin to the antenna pin through the
reserved resistorpad. Re-solderthe resistorwhich connectsthe antenna pin toon-board antenna, to
connectthe antenna pin to thePANTpin.
6. Recommended bondingpadsize forBLE2U-C
7. Layout
The upperpart ofthe moduleisthe onboardantenna,and the layoutofantenna isrelated toqualityof
wireless communication. Good communication qualitycanensureastabledatatransmission rate. The
modulecan run separatelywithoutextraground plane, butwhen it isinstalled on the otherPCB,it shouldbe
noted:Antenna area mustbe farawayfromothermetalcomponents,and the distance mustbe greaterthan
20mm.Anyconductornearthe antennamayseriouslyaffectthe antenna radiation pattern.
Symbol
Value Unit
A 18.02
mm
B 15.26
C 0.99
E 1.27
F 3.12
G 3.18
H 1.27
J 1.8
K 1
