TL16C554, TL16C554I

ASYNCHRONOUS COMMUNICATIONS ELEMENT

SLLS165D – JANUARY 1994 – REVISED JULY 1998

8

POST OFFICE BOX 655303

transmitter switching characteristics over recommended ranges of operating free-air temperature

and supply voltage (see Figures 6, 7, and 8)

PARAMETER

TEST CONDITIONS

MIN

MAX

UNIT

td5

Delay time, INTx

↓ to TXx↓ at start

8

24

RCLK

cycles

td6

Delay time, TXx

↓ at start to INTx↑

See Note 5

8

8

RCLK

cycles

td7

Delay time, IOW high or low (WR THR) to INTx

↑

See Note 5

16

32

RCLK

cycles

td8

Delay time, TXx

↓ at start to TXRDY↓

CL = 100 pF

8

RCLK

cycles

tpd1

Propagation delay time, IOW (WR THR)

↓ to INTx↓

CL = 100 pF

35

ns

tpd2

Propagation delay time, IOR (RD IIR)

↑ to INTx↓

CL = 100 pF

30

ns

tpd3

Propagation delay time, IOW (WR THR)

↑ to TXRDY↑

CL = 100 pF

50

ns

NOTE 5: If the transmitter interrupt delay is active, this delay is lengthened by one character time minus the last stop bit time.

receiver switching characteristics over recommended ranges of operating free-air temperature

and supply voltage (see Figures 9 through 13)

PARAMETER

TEST CONDITIONS

MIN

MAX

UNIT

td9

Delay time, stop bit to INTx

↑ or stop bit to RXRDY↓ or read RBR to set interrupt

See Note 6

1

RCLK

cycle

tpd4

Propagation delay time, Read RBR/LSR to INTx

↓/LSR interrupt↓

CL = 100 pF,

See Note 7

40

ns

tpd5

Propagation delay time, IOR RCLK

↓ to RXRDY↑

See Note 7

30

ns

NOTES:

6. The receiver data available indicator, the overrun error indicator, the trigger level interrupts, and the active RXRDY indicator are

delayed three RCLK (internal receiver timing clock) cycles in the FIFO mode (FCR0 = 1). After the first byte has been received, status

indicators (PE, FE, BI) are delayed three RCLK cycles. These indicators are updated immediately for any further bytes received after

IOR goes active for a read from the RBR register. There are eight RCLK cycle delays for trigger change level interrupts.

7. RCLK is an internal signal derived from divisor latch LSB (DLL) and divisor latch MSB (DLM) divisor latches.

modem control switching characteristics over recommended ranges of operating free-air

PARAMETER

MIN

MAX

UNIT

tpd6

Propagation delay time, IOW (WR MCR)

↑ to RTSx, DTRx↑

50

ns

tpd7

Propagation delay time, modem input CTSx, DSRx, and DCDx

↓↑ to INTx↑

30

ns

tpd8

Propagation delay time, IOR (RD MSR)

↑ to interrupt↓

35

ns

tpd9

Propagation delay time, RIx

↑ to INTx↑

30

ns