ST16C2550IQ48 参数 Datasheet PDF下载

DUAL UART WITH 16-BYTE TRANSMIT

AND RECEIVE FIFO’S

ST16C2550

DESCRIPTION

The ST16C2550 (2550) is a dual universal asynchronous receiver and transmitter (UART). The ST16C2550 is

an improved version of the NS16C550 UART with higher operating speed and lower access time. The 2550

provides enhanced UART functions with 16 byte FIFO’s, a modem control interface, and data rates up to 1.5Mbps.

Onboard status registers provide the user with error indications and operational status. System interrupts and

modem control features may be tailored by external software to meet specific user requirements. An internal loop-

back capability allows onboard diagnostics. Independent programmable baud rate generators are provided to

select transmit and receive clock rates from 50 Bps to 1.5 Mbps. The Baud rate generator can be configured for

either crystal or external clock input. The 2550 is available in a 40-pin plastic-DIP, 44-pin PLCC, and 48-pin TQFP

packages. The 40 pin package does not offer TXRDY and RXRDY pins (DMA Signal monitoring). Otherwise the

three package versions are the same. The 2550 is functionally compatible with the 16C2450. The 2550 is

fabricated in an advanced CMOS process to achieve low drain power and high speed requirements.

FEATURES

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Pin and functionally compatible to ST16C2450/

Software compatible with INS8250, NS16C550

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1.5Mbps transmit/receive operation (24MHz

Max.)

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16 byte transmit FIFO to reduce the bandwidth

requirement of the external CPU.

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16 byte receive FIFO with error flags to reduce the

bandwidth requirement of the external CPU.

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Independent transmit and receive UART control

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Four selectable Receive FIFO interrupt trigger

levels

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Modem control signals (-CTS, -RTS, -DSR, -DTR,

-RI, -CD, and Software controllable line break)

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Programmable character lengths (5, 6, 7, 8) with

Even, odd, or no parity

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Status report register

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Crystal or external clock input

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460.8 Kbps transmit/receive operation with 7.3728

MHz crystal or external clock source

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TTL compatible inputs, outputs

PLCC Package

-TXRDYA

-DSRA

41

44

43

42

D5

D6

D7

RXB

RXA

-TXRDYB

TXA

TXB

-OPB

-CSA

-CSB

7

8

9

10

11

12

13

14

15

16

17

XTAL1 18

XTAL2 19

-IOW 20

-CDB 21

GND 22

-RXRDYB 23

-IOR 24

-DSRB 25

-RIB 26

-RTSB 27

-CTSB 28

40

6

5

4

3

2

1

-CTSA

-CDA

VCC

-RIA

D4

D3

D2

D1

D0

39

38

37

36

35

RESET

-DTRB

-DTRA

-RTSA

-OPA

-RXRDYA

INTA

INTB

A0

A1

A2

ST16C2550CJ44

34

33

32

31

30

29

ORDERING INFORMATION

Part number

ST16C2550CP40 40

ST16C2550CJ44 44

ST16C2550CQ48 48

Pins Package

PDIP

PLCC

TQFP

Operating temperature

0° C to + 70° C

0° C to + 70° C

0° C to + 70° C

Part number

ST16C2550IP40

ST16C2550IJ44

ST16C2550IQ48

40

44

48

Pins Package

PDIP

PLCC

TQFP

Operating temperature

-40° C to + 85° C

-40° C to + 85° C

-40° C to + 85° C

Rev. 3.20

EXAR

Corporation, 48720 Kato Road, Fremont, CA 94538

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(510) 668-7000

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FAX (510) 668-7017