SC68C752BIB48.128 NXP Semiconductors, SC68C752BIB48.128 Datasheet - Page 7

• Manufacturer Part Number: SC68C752BIB48.128
• Manufacturer: NXP Semiconductors

Specifications of SC68C752BIB48.128

• Transmit Fifo: 64Byte
• Receive Fifo: 64Byte
• Transmitter And Receiver Fifo Counter: Yes
• Data Rate: 5Mbps
• Package Type: LQFP
• Operating Supply Voltage (max): 5.5V
• Mounting: Surface Mount
• Pin Count: 48
• Operating Temperature (min): -40C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Industrial
• Number Of Channels: 2
• Lead Free Status / RoHS Status: Compliant

NXP Semiconductors
[1]
6. Functional description
SC68C752B_4
Product data sheet
HVQFN32 package die supply ground is connected to both GND pin and exposed center pad. GND pin must be connected to supply
ground for proper device operation. For enhanced thermal, electrical, and board level performance, the exposed pad needs to be
soldered to the board using a corresponding thermal pad on the board and for proper heat conduction through the board, thermal vias
need to be incorporated in the PCB in the thermal pad region.
6.1 Trigger levels
6.2 Hardware flow control
Table 3.
The UART will perform serial-to-parallel conversion on data characters received from
peripheral devices or modems, and parallel-to-parallel conversion on data characters
transmitted by the processor. The complete status of each channel of the SC68C752B
UART can be read at any time during functional operation by the processor.
The SC68C752B can be placed in an alternate mode (FIFO mode) relieving the processor
of excessive software overhead by buffering received/transmitted characters. Both the
receiver and transmitter FIFOs can store up to 64 bytes (including three additional bits of
error status per byte for the receiver FIFO) and have selectable or programmable trigger
levels. Primary outputs RXRDYn and TXRDYn allow signalling of DMA transfers.
The SC68C752B has selectable hardware flow control and software flow control.
Hardware flow control significantly reduces software overhead and increases system
efficiency by automatically controlling serial data flow using the RTSn output and CTSn
input signals. Software flow control automatically controls data flow by using
programmable Xon/Xoff characters.
The UART includes a programmable baud rate generator that can divide the timing
reference clock input by a divisor between 1 and (2
The SC68C752B provides independent selectable and programmable trigger levels for
both receiver and transmitter DMA and interrupt generation. After reset, both transmitter
and receiver FIFOs are disabled and so, in effect, the trigger level is the default value of
one byte. The selectable trigger levels are available via the FCR. The programmable
trigger levels are available via the Trigger Level Register (TLR).
Hardware flow control is comprised of auto-CTS and auto-RTS. Auto-CTS and auto-RTS
can be enabled/disabled independently by programming EFR[7:6].
With auto-CTS, CTSn must be active before the UART can transmit data.
Auto-RTS only activates the RTSn output when there is enough room in the FIFO to
receive data and de-activates the RTSn output when the receive FIFO is sufficiently full.
The halt and resume trigger levels in the TCR determine the levels at which RTSn is
activated/deactivated.
CS
1
0
0
Channel selection using CS pin
A3
-
0
1
5 V, 3.3 V and 2.5 V dual UART, 5 Mbit/s (max.), with 64-byte FIFOs
Rev. 04 — 20 January 2010
UART channel
none
channel A
channel B
16
− 1).
SC68C752B
© NXP B.V. 2010. All rights reserved.
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