SN75276

FAIL-SAFE DIFFERENTIAL BUS TRANSCEIVER

SLLS212B – SEPTEMBER 1995 – REVISED APRIL 1998

6

POST OFFICE BOX 655303

DRIVER SECTION

SYMBOL EQUIVALENTS

DATA-SHEET PARAMETER

TIA/EIA-422-B

TIA/EIA-485-A

VO

Voa, Vob

Voa, Vob

|VOD1|

Vo

Vo

|VOD2|

Vt (RL = 100 Ω)

Vt (RL = 54 Ω)

VOD3

None

Vt (Test Termination

Measurement 2)

∆|VOD|

||Vt| – |Vt||

||Vt – |Vt||

VOC

|Vos|

|Vos|

∆|VOC|

|Vos – Vos|

|Vos – Vos|

IOS

|Isa|, |Isb|

IO

|Ixa|, |Ixb|

Iia, Iib

RECEIVER SECTION

electrical characteristics over recommended ranges of common-mode input voltage, supply

voltage, and operating free-air temperature (unless otherwise noted)

PARAMETER

TEST CONDITIONS

MIN

TYP†

MAX

UNIT

VIT +

Positive-going input threshold voltage

VO = 2.7 V,

IO = – 0.4 mA

0

V

VIT –

Negative-going input threshold voltage

VO = 0.5 V,

IO = 8 mA

– 0.3‡

V

VIK

Enable clamp voltage

II = – 18 mA

– 1.5

V

VOH

High level output voltage

VID = 0,

IOH = – 400 µA,

27

V

VOH

High-level output voltage

ID

,

See Figure 2

OH

µ ,

2.7

V

VOL

Low level output voltage

VID = – 300 mV,

IOL = 8 mA,

045

V

VOL

Low-level output voltage

ID

,

See Figure 2

OL

,

0.45

V

IOZ

High-impedance-state output current

VO = 0.4 V to 2.4 V

±20

µA

II

Line input current

Other input = 0 V,

VI = 12 V

1

mA

II

Line input current

,

See Note 5

VI = – 7 V

– 0.8

mA

IIH

High-level enable input current

VIH = 2.7 V

20

µA

IIL

Low-level enable input current

VIL = 0.4 V

– 100

µA

ri

Input resistance

VI = 12 V

12

k

Ω

IOS

Short-circuit output current

–15

–85

mA

ICC

Supply current (total package)

No load

Outputs enabled

42

55

mA

ICC

Supply current (total package)

No load

Outputs disabled

26

35

mA

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

‡ The algebraic convention, in which the less positive (more negative) limit is designated minimum, is used in this data sheet for negative-going

input threshold voltage levels only.

NOTE 5: This applies for both power on and power off. Refer to TIA/EIA-485-A for exact conditions.