SGS Thomson Microelectronics ST75C176CN, ST75C176CD, ST75C176CDR, ST75C176BN, ST75C176BDR Datasheet

■ LOW QUIESCENT CURRE NT: 300µA

■ DESIGNED FOR RS-485 INTERFACE

APPLICATIONS

■ -7V TO 12V COMMON MODE INPUT

VOLTAGE RANGE

■ DRIVER MAINTAINS HIGH IMPEDANCE IN

3-STATEORWITHTHEPOWEROFF

■ 70mV TYPICAL INPUTHYSTERESIS

■ 30ns PROPAGATION DELAYS, 5ns SKEW

■ OPERATE FROM A SINGLE 5V SUPPLY

■ CURRENT LIMITING AND T HER MAL

SHUTDOWN FOR DRIVER OVERLOAD
PROTECTION

■ ALLOWS UP TO 32 TRANSCEIVERS ON

THE BUS

■ BIC MOS TECHNOLOG Y

DESCRIPTION

The ST75C176 is al low power transceiver for
RS-485 and RS-422 communication. Each part
contains one driver and one rec eiver.
This transceiver draw 300µA (typ.) of supply
current when unlo aded or fully loaded with
disabled drivers.

ST75C176

LOW POWER

RS-485/RS-422 TRANSCEIVER

DIP SOP

It operates from a single 5V s upply.
Driver is short-circuit current limited and is
protected against excessive power diss ipation by
thermal shutdown circuitry that placed the driver
outputs into a high-impedance state. The receiver
input has a fail safe feature that guarantees a
logic-high output if the input is open circuit.
The ST75C176 is designed for bi-directional data
communications on multipoint bus transmission
line (half-duplex applciations).

ORDERING CODES

Type

ST75C176CN 0 to 70 °C DIP-8 50parts per tube /40tube per box
ST75C176BN -40 to 85 °C DIP-8 50parts per tube / 40tube per box
ST75C176CD 0 to 70 °C SO-8 (Tube) 100parts per tube / 20tube per box

ST75C176BD -40 to 85 °C SO-8 (Tube) 100parts per tube / 20tube per box
ST75C176CDR 0 to 70 °C SO-8 (Tape & Reel) 2500 parts per reel
ST75C176BDR -40 to 85 °C SO-8 (Tape & Reel) 2500 parts per reel

Temperature

Range

Package Comments

1/13June 2003

ST75C176

PIN CONFIGURATION

PIN DESCRIPTION

PlN N° SYMBOL NAME AND FUNCTION

1 RO Receiver Output
2RE
3 DE Driver Output Enable
4 DI Driver Input
5 GND Ground
6 A Non-inverting Receiver Input and Non-inverting Driver Output
7 B Inverting Receiver Input and Inverting Driver Output
8

Receiver Output Enable

V

CC

Supply Voltage

TRUTH TABLE (DRIVER)

INPUTS OUTPUTS

RE

XHHLH
XHLHL
XLXZZ

X= Don’t Care; Z=High Impedance

DE DI B A

TRUTH TABLE (RECEIVER)

INPUTS OUTPUT

RE

LL≥ +0.2V H
LL≤ -0.2V L
L L INPUTS OPEN H

HL X Z

X= Don’t Care; Z=High Impedance

DE A-B RO

ABSOLUTE MAXIMUM RATINGS

Symbol Parameter Value Unit

V

V

V

V

V

V

Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is
not implied.

Supply Voltage

CC

Control Input Voltage (RE, DE) -0.5 to (VCC+ 0.5)

I

Driver Input Voltage (DI) -0.5 to (VCC+ 0.5)

DI

Driver Output Voltage (A, B)

DO

Receiver Input Voltage (A, B)

RI

Receiver Output Voltage (RO) -0.5 to (VCC+ 0.5)

RO

7V

V
V

± 14 V
± 14 V

V

2/13

ST75C176

DC ELECTRICAL CHARACTERISTICS

(V

=5V± 5%,TA=T

CC

(See Note 1)

Symbol Parameter Test Conditions Min. Typ. Max. Unit

V

V

∆V

V

∆V

V

∆V

V

V

I

I

OSD1

I

OSD2

I

Note 1: All currents into device pins are positive; all cuttents out of device pins are negative; all voltages are referenced to device ground
unless specified.

Note 2: Supply current specification is valid for loaded transmitters when V
Note 3: Applies to peak current. See typical Operating Characteristics.

Differential Driver Output

OD1

(No Load)
Differential Driver Output

OD2

(With Load)
Change in Magnitude of

OD

Driver Differential Output
Voltage for Complementary
Output States

Driver Common-Mode

OC

Output Voltage
Change in Magnitude of

OC

Driver Common-Mode
Output Voltage for
Complementary Output
States

V

Input High Voltage RE, DE, DI 2.0 V

IH

Input Low Voltage RE, DE, DI 0.8 V

V

IL

Input Current RE, DE, DI ± 2 µA

I

IN1

Input Current (A, B) VCM= 0V or 5.25V VDE=0V

I

IN2

Receiver Differential

TH

Threshold Voltage
Receiver Input Hysteresis VCM=0V 70 mV

TH

Receiver Output High

OH

Voltage
Receiver Output Low

OL

Voltage
3-State (High Impedance)

OZR

Output Current at Receiver
Receiver Input Resistance VCM= -7 to 12V 12 KΩ

R

IN

No Load Supply Current

I

CC

(Note 2)

Driver Short-Circuit Current,

=High

V

O

Driver Short-Circuit Current,

=Low

V

O

Receiver Short-Circuit

OSR

Current

MIN

to T

, unles s otherwise s pec ified. Typical v alues are referred to TA= 25°C)

MAX

5V

RL=27Ω (RS-485) (See Fig. 1)
R

=50Ω (RS-422) (See Fig. 1)

L

=27Ω or 50Ω (See Fig. 1) 0.2 V

R

L

1.5 5
5

RL=27Ω or 50Ω (See Fig. 1) 3 V

=27Ω or 50Ω (See Fig. 1) 0.2 V

R

L

V
V

IN
IN

= 12V
= -7V

1

-0.8

VCM= -7 to 12V -0.2 0.2 V

IO= -4mA VID= 200mV 3.5 V

IO=4mA VID= -200mV 0.4 V

VO= 0.4 to 2.4V ± 1 µA

VRE=0VorV
VDE=V
VDE=0V

V

= -7 to 12V (Note 3) 35 250 mA

O

V

= -7 to 12V (Note 3) 35 250 mA

O

VO=0VtoV

CC

CC

CC

DE

=0V

400
300

900
500

795mA

V
V

mA
mA

µA
µA

3/13

ST75C176

DRIVER SWITCHING CHARACTERISTICS

(V

=5V± 5%,TA=T

CC

(See Note 1)

Symbol Parameter Test Conditions Min. Typ. Max. Unit

t

t
t

t

t

t

t

Note 1: All currents into device pins are positive; all cuttents out of device pins are negative; all voltages are referenced to device ground
unless specified.

Propagation Delay Input to

PLH

Output

t

PHL

t

Output Skew to Output R

SK

Rise or Fall Time R

TLH
THL

Output Enable Time CL= 100pF S2 = Closed

PZH

Output Enable Time CL= 100pF S1 = Closed

PZL

Output Disable Time CL= 15pF S1 = Closed

PLZ

Output Disable Time CL= 15pF S2 = Closed

PHZ

MIN

toT

,unless otherwise specified. Typical values arereferred to TA=25°C)

MAX

R

=54Ω CL1=CL2= 100pF

DIFF

10 30 60 ns

(See Fig. 3 and 5)

=54Ω CL1=CL2= 100pF

DIFF

510ns

(See Fig. 3 and 5)

=54Ω CL1=CL2= 100pF

DIFF

31540ns

(See Fig. 3 and 5)

40 70 ns

(See Fig. 4 and 6)

40 70 ns

(See Fig. 4 and 6)

40 70 ns

(See Fig. 4 and 6)

40 70 ns

(See Fig. 4 and 6)

RECEIVER SWITCHING CHARACTERISTICS

(V

=5V± 5%,TA=T

CC

MIN

to T

, unles s otherwise s pec ified. Typical v alues are referred to TA= 25°C)

MAX

(See Note 1)

Symbol Parameter Test Conditions Min. Typ. Max. Unit

t

t

t

t

t

t

f

Note 1: All currents into device pins are positive; all cuttents out of device pins are negative; all voltages are referenced to device ground
unless specified.

Propagation Delay Input to

PLH

Output

t

PHL

Differential Receiver Skew R

SKD

Output Enable Time CRL= 15pF S1 = Closed

PZH

Output Enable Time CRL= 15pF S2 = Closed

PZL

Output Disable Time CRL= 15pF S1 = Closed

PLZ

Output Disable Time CRL= 15pF S2 = Closed

PHZ

Maximum Data Rate 2.5 Mbps

MAX

R

=54Ω CL1=CL2= 100pF

DIFF

(See Fig. 3 and 7)

=54Ω CL1=CL2= 100pF

DIFF

(See Fig. 3 and 7)

(See Fig. 2 and 8)

(See Fig. 2 and 8)

(See Fig. 2 and 8)

(See Fig. 2 and 8)

20 130 210 ns

13 ns

20 50 ns

20 50 ns

20 50 ns

20 50 ns

4/13