SI2493-C-FS Silicon Laboratories Inc, SI2493-C-FS Datasheet - Page 100

• Manufacturer Part Number: SI2493-C-FS
• Description: IC ISOMODEM SYSTEM-SIDE 16SOIC
• Manufacturer: Silicon Laboratories Inc

Specifications of SI2493-C-FS

• Mfg Application Notes: SI2493/57/34/15/04, Appl Note AN93
• Data Format: V.21, V.22, V.23, V.29, V.32, V.34, V.90, V.92, Bell 103, Bell 212A
• Baud Rates: 56k
• Interface: UART
• Voltage - Supply: 3 V ~ 3.6 V
• Mounting Type: Surface Mount
• Package / Case: 16-SOIC (3.9mm Width)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

AN93
The DCD and RI pins can be used as a hardware monitor of carrier detect and ring signals. Additionally, the INT pin
can be programmed to monitor the bits in register U70 listed in Table 70. The RI, PPD, OCD, CID, and RST bits are
sticky, and the AT:I command reads and clears these signals and deactivates the INT pin if INT is enabled. A block
diagram of the UART in the serial interface mode is shown in Figure 19.
100
CTS
RTS
8-Bit Data
Mode
9-Bit Data
Mode
Signal
DCD
OCD
PPD
CID
RI
RX
TX
t
t
RTS
RTS
t
UART Tim ing for Modem Transm it Path (9N1 Mode with 9th Bit Escape)
RTH
U70 Bit
Start
Start
0
1
2
3
4
Figure 18. Asychronous UART Serial Interface Timing Diagram
UART Tim e for Modem Receive Path (8N1 Mode)
D0
D0
Function
Data Carrier Detect—active high (inverse of DCD).
Ring Indicate—active high (inverse of RI).
Parallel Phone Detect.
Overcurrent Detect.
Caller ID Preamble Detect.
Table 70. Register U70 Signals INT Can Monitor
D1
D1
D2
D2
D3
D3
Rev. 0.9
D4
D4
D5
D5
D6
D6
D7
D7
ESC
Stop
Stop
t
CTH