Datasheet

 2016-2019 Microchip Technology Inc. DS50002489D-page 9
RN4870/71
FIGURE 1-5: BLOCK DIAGRAM OF THE RN4870/71
Pairing Key When the RN4870/71 is connected to a remote device, the host MCU can use
the Pairing Key pin to force the module to disconnect the link and go back to
Standby state. The pin must be pulled down for at least 160 ms.
RF Active Indication Use this indication pin to indicate that the module is currently performing an
active transmission and receiving BLE data.
TABLE 1-5: STATUS INDICATION PINS
Status 1 Status 2 State
High High Power On
High Low Standby state
Low Low Connection established
Low High Data session open (Transparent UART)
TABLE 1-6: TEST POINTS ON THE BOTTOM SIDE
RN4870U RN4870 RN4871U RN4871 Symbol Description
TP-1 TP-1 TP-3 TP-3 VCC_PA 1.55V RF PA LDO
TP-2 TP-2 TP-1 TP-5 CLDO_O 1.2V CLDO Output
TP-3 TP-3 TP-2 TP-2 VCC_RF 1.2V RF LDO Output
— — TP-4 TP-4 ULPC_O 1.2V ULPC LDO Output
— — TP-5 TP-1 BK_O 1.55V Buck Reg Output
TABLE 1-4: CONFIGURABLE FUNCTIONS AND DESCRIPTIONS (CONTINUED)
Function Name Description
RN4870/RN4871