SC16C650BIB48 NXP Semiconductors, SC16C650BIB48 Datasheet - Page 12

• Manufacturer Part Number: SC16C650BIB48
• Description: UART, 32BYTE FIFO, 16C650, LQFP48
• Manufacturer: NXP Semiconductors

Specifications of SC16C650BIB48

• No. Of Channels: 1
• Data Rate: 3Mbps
• Supply Voltage Range: 2.25V To 5.5V
• Operating Temperature Range: -40°C To +85°C
• Digital Ic Case Style: LQFP
• No. Of Pins: 48
• Svhc: No SVHC (18-Jun-2010)
• Operating: RoHS Compliant
• Uart Features: Automatic Software/Hardware Flow Control, Programmable Xon/Xoff Characters
• Rohs Compliant: Yes

NXP Semiconductors
SC16C650B_4
Product data sheet
6.7 Programmable baud rate generator
The SC16C650B supports high speed modem technologies that have increased input
data rates by employing data compression schemes. For example, a 33.6 kbit/s modem
that employs data compression may require a 115.2 kbit/s input data rate. A 128.0 kbit/s
ISDN modem that supports data compression may need an input data rate of 460.8 kbit/s.
A single baud rate generator is provided for the transmitter and receiver, allowing
independent TX/RX channel control. The programmable baud rate generator is capable of
accepting an input clock up to 48 MHz, as required for supporting a 3 Mbit/s data rate.
The SC16C650B can be configured for internal or external clock operation. For internal
clock oscillator operation, an industry standard microprocessor crystal (parallel resonant,
22 pF to 33 pF load) is connected externally between the XTAL1 and XTAL2 pins (see
Figure
internal baud rate generator for standard or custom rates (see
The generator divides the input 16 clock by any divisor from 1 to (2
SC16C650B divides the basic crystal or external clock by 16. The frequency of the
BAUDOUT output pin is exactly 16 (16 times) the selected baud rate
(BAUDOUT = 16
proper divisor values for the MSB and LSB sections of baud rate generator.
Setting MCR[7] to a logic 1 provides an additional divide-by-4, whereas setting MCR[7] to
a logic 0 only divides by 1 (see
Programming the baud rate generator registers DLM (MSB) and DLL (LSB) provides a
user capability for selecting the desired final baud rate. The example in
selectable baud rates when using a 1.8432 MHz crystal and setting MCR[7] to a logic 0.
For custom baud rates, the divisor value can be calculated using
divisor in decimal
Fig 5.
5). Alternatively, an external clock can be connected to the XTAL1 pin to clock the
Crystal oscillator connection
baud rate). Customized baud rates can be achieved by selecting the
Rev. 04 — 14 September 2009
=
XTAL1
XTAL1 clock frequency
--------------------------------------------------------------- -
1.8432 MHz
serial data rate 16
C1
22 pF
X1
Table 5
XTAL2
UART with 32-byte FIFOs and IrDA encoder/decoder
C2
33 pF
and
Figure
XTAL1
6).
1.8432 MHz
C1
22 pF
X1
XTAL2
002aaa870
Table
1.5 k
C2
47 pF
SC16C650B
Equation
16
5).
© NXP B.V. 2009. All rights reserved.
Table 5
1). The
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