XR20M1172IG28-F Exar Corporation, XR20M1172IG28-F Datasheet - Page 16

• Manufacturer Part Number: XR20M1172IG28-F
• Description: IC UART FIFO I2C/SPI 64B 28TSSOP
• Manufacturer: Exar Corporation

Specifications of XR20M1172IG28-F

• Number Of Channels: 2, DUART
• Package / Case: 28-TSSOP (0.173", 4.40mm Width)
• Features: *
• Fifo's: 64 Byte
• Protocol: RS485
• Voltage - Supply: 1.62 V ~ 3.63 V
• With Auto Flow Control: Yes
• With Irda Encoder/decoder: Yes
• With False Start Bit Detection: Yes
• With Modem Control: Yes
• With Cmos: Yes
• Mounting Type: Surface Mount
• Data Rate: 16 Mbps
• Supply Voltage (max): 3.6 V
• Supply Voltage (min): 1.62 V
• Supply Current: 250 uA
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• No. Of Channels: 2
• Uart Features: Tx/Rx FIFO Counters
• Supply Voltage Range: 1.62V To 3.63V
• Operating Temperature Range: -40°C To +85°C
• Digital Ic Case Style: TSSOP
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 1016-1298-5

XR20M1172
TWO CHANNEL I2C/SPI UART WITH 64-BYTE FIFO
The transmit holding register is an 8-bit register providing a data interface to the host processor. The host
writes transmit data byte to the THR to be converted into a serial data stream including start-bit, data bits,
parity-bit and stop-bit(s). The least-significant-bit (Bit-0) becomes first data bit to go out. The THR is the input
register to the transmit FIFO of 64 bytes when FIFO operation is enabled by FCR bit-0. Every time a write
operation is made to the THR, the FIFO data pointer is automatically bumped to the next sequential data
location.
The host loads transmit data to THR one character at a time. The THR empty flag (LSR bit-5) is set when the
data byte is transferred to TSR. THR flag can generate a transmit empty interrupt (ISR bit-1) when it is enabled
by IER bit-1. The TSR flag (LSR bit-6) is set when TSR becomes completely empty.
The host may fill the transmit FIFO with up to 64 bytes of transmit data. The THR empty flag (LSR bit-5) is set
whenever the FIFO is empty. The THR empty flag can generate a transmit empty interrupt (ISR bit-1) when the
amount of data in the FIFO falls below its programmed trigger level. The transmit empty interrupt is enabled by
IER bit-1. The TSR flag (LSR bit-6) is set when TSR/FIFO becomes empty.
F
F
2.7.1
2.7.2
2.7.3
IGURE
IGURE
13. T
14. T
Transmit Holding Register (THR) - Write Only
Transmitter Operation in non-FIFO Mode
Transmitter Operation in FIFO Mode
RANSMITTER
RANSMITTER
16X or 8X or 4X Clock
Auto CTS Flow Control (CTS# pin)
(Xoff1/2 and Xon1/2 Reg.)
Auto Software Flow Control
Flow Control Characters
( DLD[5:4] )
16X or 8X or 4X
( DLD[5:4] )
O
O
Clock
PERATION IN NON
PERATION IN
Data
Byte
Data Byte
Transmit
Transmit Shift Register (TSR)
FIFO
-FIFO M
Transmit
Register
Holding
(THR)
Transm it Data Shift Register
AND
F
LOW
ODE
(TSR)
Transmit
16
FIFO
C
ONTROL
THR Interrupt (ISR bit-1)
Enabled by IER bit-1
M
THR Interrupt (ISR bit-1) falls
below the programmed Trigger
Level and then when becomes
empty. FIFO is Enabled by FCR
bit-0=1
ODE
M
S
B
L
S
B
TXNOFIFO1
TXFIFO 1
REV. 1.0.1