ADM3095E

Data Sheet

Rev. C | Page 4 of 19

TIMING SPECIFICATIONS

VCC = 3.0 V to 5.5 V, VIO = 1.62 V to VCC, TA = TMIN (−40°C), to TMAX (125°C), unless otherwise noted.

Table 2.

Parameter

Min

Typ

Max

Unit

Test Conditions/Comments

DRIVER

Data Rate

2.5

Mbps

Propagation Delay (tPLH, tPHL)

35

500

ns

RLDIFF = 54 Ω, CL1 = CL2 = 100 pF; see Figure 2 and Figure 27

Differential Skew (tSKEW)

10

50

ns

RLDIFF = 54 Ω, CL1 = CL2 = 100 pF; see Figure 2 and Figure 27

Rise/Fall Times (tR, tF)

40

130

ns

RLDIFF = 54 Ω, CL1 = CL2 = 100 pF; see Figure 2 and Figure 27

Enable Time (tZH, tZL)

500

2500

ns

RL = 110 Ω, CL = 50 pF, see Figure 4 and Figure 28

Disable Time (tHZ, tLZ)

500

2500

ns

RL = 110 Ω, CL = 50 pF, see Figure 4 and Figure 28

Enable Time from Shutdown

4000

5500

ns

RL = 110 Ω, CL = 50 pF, see Figure 4 and Figure 28

RECEIVER

Propagation Delay (tPLH, tPHL)

120

200

ns

CL = +15 pF, VID1 ≥ ±1.5 V; see Figure 3 and Figure 29

140

220

ns

CL = +15 pF, VID1 ≥ ±600 mV; see Figure 3 and Figure 29

Skew (tSKEW)

4

40

ns

CL = +15 pF, VID1 ≥ ±1.5 V; see Figure 3 and Figure 29

Enable Time

12

55

ns

RL = 1 kΩ, CL = 15 pF; see Figure 5 and Figure 30

Disable Time

12

55

ns

RL = 1 kΩ, CL = 15 pF; see Figure 5 and Figure 30

Enable Time from Shutdown

3000

4500

ns

RL = 1 kΩ, CL = 15 pF; see Figure 5 and Figure 30

Time to Shutdown

50

330

3000

ns

RL = 1 kΩ, CL = 15 pF; see Figure 5 and Figure 30

Rx, Pulse Width Distortion

40

ns

CL = +15 pF, VID1 ≥ ±1.5 V; see Figure 3 and Figure 29

1

VID is the input differential voltage to the RS-485 receiver.

TIMING DIAGRAMS

VIO

TxD

VDIFF

0V

VOD

+VOD

–VOD

A

B

VO

tDR

tDF

tPLH

tPHL

90% POINT

10% POINT

90% POINT

10% POINT

VDIFF = (VA) – (VB)

1/2VOD

1/2VIO

1/2VIO

NOTES

1. VOD IS THE DIFFERENCE BETWEEN A AND B,

WITH +VOD BEING THE MAXIMUM POINT OF VOD,

AND –VOD BEING THE MINIMUM POINT OF VOD.

Figure 2. Driver Propagation Delay, Rise/Fall Timing Diagram

1/2VIO

1/2VIO

tPLH

tPHL

RxD

VOH

0V

A – B

0V

VOL

tSKEW = |tPLH – tPHL|

Figure 3. Receiver Propagation Delay Timing Diagram

A OR B

A OR B

DE

VIO

0V

0V

VOH

VOL

1/2VIO

1/2VIO

1/2VCC

1/2VCC

tLZ

tZL

tHZ

tZH

VOL + 0.5V

VOH – 0.5V

Figure 4. Driver Enable/Disable Timing Diagram

RxD

RxD

RE

VIO

0V

0V

1/2VIO

1/2VIO

OUTPUT HIGH

OUTPUT LOW

tLZ

tZL

tHZ

tZH

VOL + 0.5V

VOH – 0.5V

VOH

VOL

1/2VIO

1/2VIO

Figure 5. Receiver Enable/Disable Timing Diagram