Datasheet

Pin settings ST7538Q
6/44
2.2 Pin description
Table 1. Pin description
Pin N° Name Type Description
1 CD_PD Digital/Output Carrier, Preamble or Frame Header Detect Output.
"1" No Carrier, Preamble or Frame Header Detected
"0" Carrier, Preamble or Frame Header Detected
2 DVss Supply Digital Ground
3 RxD Digital/Output RX Data Output.
4 RxTx Digital/Input
with internal pull-up
Rx or Tx mode selection input.
"1" - RX Session
"0" - TX Session
5 TxD Digital/Input
with internal pull-down
TX Data Input.
6 GND Supply Substrate Ground (same function as PIN 41)
7 TOUT Digital/Output TX Time Out Event Detection
"1" - Time Out Event Occurred
"0" - No Time-out Event Occurred
8 CLR/T Digital/Output Synchronous Mains Access Clock or
Control Register Access Clock
9 BU Digital/Output Band in use Output.
"1" Signal within the Programmed Band
"0" No Signal within the Programmed Band
10 DVdd Supply Digital Supply Voltage or 3.3V Voltage Regulator Output
11 MCLK Digital/Output Master Clock Output
12 RSTO Digital/Output Power On or Watchdog Reset Output
13 UART/SPI Digital/Input
with internal pull-down
Interface type:
“0” - Serial Peripheral Interface
“1” - UART Interface
14 WD Digital/Input
with internal pull-up
Watchdog input. The Internal Watchdog Counter is cleared on the
falling edges.
15 ZCOUT Digital/Output Zero Crossing Detection Output
16
ZCIN
(1)
Analog/Input Zero Crossing AC Input.
17 NC Floating Must be connected to DVss.
18 DVss Supply Digital Ground
19 ATOP1 Power/Output Power Line Driver Output
20 PAVss Supply Power Analog Ground
21 ATOP2 Power/Output Power Line Driver Output
22 PAV
CC
Supply Power Supply Voltage
23
CL
(2)
Analog/Input Current Limiting Feedback.
A resistor between CL and AVss sets the PLI Current Limiting Value
An integrated 80pF filtering input capacitance is present on this pin
24 ATO Analog/Output Small Signal Analog Transmit Output