Quectel EC21-A User Manual

LTE Standard Module Series
EC21_Series_Hardware_Design
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7
The PCM function of pins 24–27 can be used for audio design on EC21 series module and Bluetooth function on FC20
series/FC21 modules.
SDC1_DATA1 131 DIO WLAN SDIO data bit 1
SDC1_DATA0 132 DIO WLAN SDIO data bit 0
SDC1_CLK 133 DO WLAN SDIO clock
SDC1_CMD 134 DIO WLAN SDIO command
WLAN_EN 136 DO WLAN function enable
1.8 V power domain
Active high.
Cannot be pulled up before startup.
If unused, keep it open.
Coexistence and Control Interface
PM_ENABLE 127 DO WLAN power control
1.8 V power domain.
Active high.
If unused, keep it open.
WAKE_ON_
WIRELESS
135 DI
WLAN wake up the
module
1.8 V power domain.
Active low.
If unused, keep it open.
COEX_UART_RX 137 DI
LTE/WLAN & Bluetooth
coexistence receive
1.8 V power domain.
Cannot be pulled up before startup.
If unused, keep them open.
COEX_UART_TX 138 DO
LTE/WLAN & Bluetooth
coexistence transmit
WLAN_SLP_CLK 118 DO WLAN sleep clock If unused, keep it open.
Bluetooth Application Interface
BT_RTS 37 DI
DTE request to send
signal from DCE
1.8 V power domain.
If unused, keep them open.
BT_TXD 38 DO Bluetooth UART transmit
BT_RXD 39 DI Bluetooth UART receive
BT_CTS 40 DO
DTE clear to send signal
from DCE
1.8 V power domain
Cannot be pulled up before startup.
If unused, keep it open.
BT_EN 139 DO
Bluetooth function
enable
1.8 V power domain
Active high.
If unused, keep them open.
PCM Interface
7
PCM_IN 24 DI PCM data input
1.8 V power domain.
If unused, keep them open.
PCM_OUT 25 DO PCM data output

Quectel EC21-A Specifications

General

Brand	Quectel
Model	EC21-A
Category	Control Unit
Language	English