SN75ALS170, SN75ALS170A

TRIPLE DIFFERENTIAL BUS TRANSCEIVER

SLLS055D – AUGUST 1987 – REVISED SEPTEMBER 1995

6

POST OFFICE BOX 655303

switching characteristics over recommended ranges of supply voltage and operating free-air

temperature (unless otherwise noted)

PARAMETER

TEST CONDITIONS

MIN

TYP†

MAX

UNIT

ALS170

RL = 54 Ω,

CL = 50 pF,

3

8

13

ALS170A

L

,

TA =25°C,

L

,

See Figure 3

5.5

8

10.5

td(OD)

Differential output delay time

ALS170

RL1 = RL3 = 165 Ω,

CL =60 pF

RL2 = 75 Ω,

TA =25°C

3

8

13

ns

ALS170A

CL = 60 pF,

See Figure 4

TA =25°C,

5.5

8

10.5

t k( )

Pulse skew‡

RL = 54 Ω,

See Figure 3

CL = 50 pF,

1

5

ns

tsk(p)

Pulse skew‡

RL1 = RL3 = 165 Ω,

CL = 60 pF,

RL2 = 75 Ω,

See Figure 4

1

5

ns

§

ALS170

RL = 54 Ω,

CL = 50 pF,

10

t k(li )

Skew limit§

ALS170A

L

,

See Figure 3

L

,

5

ns

tsk(lim)

Skew limit§

ALS170

RL1 = RL3 = 165 Ω,

RL2 = 75 Ω,

10

ns

ALS170A

L1

L3

,

CL = 60 pF,

L2

,

See Figure 4

5

tt(OD)

Differential output transition time

RL = 54 Ω,

See Figure 3

CL = 50 pF,

3

8

13

ns

tt(OD)

Differential-output transition time

RL1 = RL3 = 165 Ω,

CL = 60 pF,

RL2 = 75 Ω,

See Figure 4

3

8

13

ns

† All typical values are at VCC = 5 V and TA = 25°C.

‡ Pulse skew is defined as the | td(ODH)–td(ODL)| of each channel.

§ Skew limit is the maximum difference in propagation delay times between any two channels of one device and between any two devices. This

parameter is applicable at one VCC and operating temperature within the recommended operating conditions.

SYMBOL EQUIVALENTS

DATA SHEET PARAMETER

EIA/TIA-422-B

RS-485

VO

Voa, Vob

Voa, Vob

| VOD1 |

VO

VO

| VOD2 |

Vt (RL = 100 Ω)

Vt (RL = 54 Ω)

| VOD3 |

Vt (Test Termination

Measurement 2)

Vtest

Vtst

∆ | VOD |

|| Vt | – | Vt ||

|| Vt | – | Vt ||

VOC

| Vos |

| Vos |

∆ | VOC |

| Vos – Vos |

| Vos – Vos |

IOS

| Isa |, | Isb |

IO

| Ixa |, | Ixb |

Iia, Iib