TLK1521

500 Mbps to 1.3 Gbps TRANSCEIVER

SLLS591A− OCTOBER 2003 − REVISED JANUARY 2004

11

POST OFFICE BOX 655303

TTL input electrical characteristics over recommended operating conditions (unless otherwise

noted)

TTL Signals: TXD0 ...TXD17, GTX_CLK, LOOPEN, SYNC, PREEMPH

PARAMETER

TEST CONDITIONS

MIN

TYP

MAX

UNIT

VIH

High-level input voltage

See Figure 6

2

3.6

V

VIL

Low-level input voltage

See Figure 6

0.8

V

IIH

High-level input current

VDD = MAX, VIN = 2 V

40

µA

IIL

Low-level input current

VDD = MAX, VIN = 0.4 V

−40

µA

CIN

Input capacitance

0.8 V to 2 V

4

pF

tr

GTX_CLK, TXD rise time

0.8 V to 2 V, C = 5 pF, See Figure 6

1

ns

tf

GTX_CLK, TXD fall time

2 V to 0.8 V, C = 5 pF, See Figure 6

1

ns

tsu

TXD setup to

↑ GTX_CLK

See Figure 6

1.5

ns

th

TXD hold to

↑ GTX_CLK

See Figure 6

0.4

ns

TXD(0−17)

2 V

0.8 V

2 V

0.8 V

GTX_CLK

tsu

th

tf

tr

0 V

0 V

tr

tf

3.6 V

3.6 V

Figure 6. TTL Data Input Valid Levels for AC Measurements