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TL16C554A_13 Datasheet, PDF (7/46 Pages) Texas Instruments – ASYNCHRONOUS-COMMUNICATIONS ELEMENT
TL16C554A, TL16C554AI
ASYNCHRONOUS-COMMUNICATIONS ELEMENT
SLLS509E − AUGUST 2001 − REVISED JUNE 2010
Terminal Functions (Continued)
NAME
TERMINAL
FN
PM
NO. NO.
PN I/O
NO.
DESCRIPTION
RIA, RIB,
RIC, RID
19, 30, 18, 43, I Ring detect indicator. A low on RIx indicates the modem has received a ring signal from
50, 63 58, 3
the telephone line. The condition of this signal can be checked by reading bit 6 of the
modem-status register.
RTSA, RTSB,
RTSC, RTSD
5, 13, 26, 35, O Request to send. When active, RTS informs the modem or data set that the ACE is ready
36, 44 66, 75
to receive data. RTS is set to the active level by setting the RTS modem-control register
bit, and is set to the inactive (high) level either as a result of a master reset, or during
loop-mode operations, or by clearing bit 1 (RTS) of the MCR. In the auto-RTS mode, RTS
is set to the inactive level by the receiver threshold-control logic.
RXA, RXB
RXC, RXD
7, 29, 20, 29, 17, 44, I Serial input. RXx is a serial-data input from a connected communications device. During
41, 63 51, 62 57, 4
loopback mode, the RXx input is disabled from external connection and connected to the
TXx output internally.
RXRDY
38
54 O Receive ready. RXRDY goes low when the receive FIFO is full. It can be used as a single
transfer or multitransfer.
TXA, TXB
TXC, TXD
17, 19, 8, 10, 29, 32, O Transmit outputs. TXx is a composite serial-data output connected to a communications
51, 53 39, 41 69, 72
device. TXA, TXB, TXC, and TXD are set to the marking (high) state as a result of reset.
TXRDY
39
55 O Transmit ready. TXRDY goes low when the transmit FIFO is full. It can be used as a single
transfer or multitransfer function.
VCC
13, 30, 21, 35, 5, 25,
Power supply
47, 64 52 45, 65
XTAL1
35
25
50
I Crystal input 1 or external clock input. A crystal can be connected to XTAL1 and XTAL2 to
utilize the internal oscillator circuit. An external clock can be connected to drive the
internal-clock circuits.
XTAL2
36
26
51 O Crystal output 2 or buffered clock output (see XTAL1).
absolute maximum ratings over free-air temperature range (unless otherwise noted)†
Supply voltage range, VCC (see Note 1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to 7 V
Input voltage range at any input, VI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to 7 V
Output voltage range, VO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −0.5 V to VCC + 3 V
Continuous total-power dissipation at (or below) 70°C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500 mW
Operating free-air temperature range, TA: TL16C554A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0°C to 70°C
TL16C554AI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −40°C to 85°C
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . −65°C to 150°C
† Stresses beyond those listed under “absolute maximum ratings” may cause permanent damage to the device. These are stress ratings only, and
functional operation of the device at these or any other conditions beyond those indicated under “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
NOTE 1: All voltage levels are with respect to GND.
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