ST ST3293 User Manual

查询ST3293供应商

■ FULL DUPLEX COMMUNICATIONS DEVICE

RS-422

■ PROGRAMMABLEEMPHASIS INCREASES

THEDISTANCEANDDATARATE

■ HIGH SPEED: DATA RATE UP TO 25Mbps

■ -7V TO 7V COMO N -MO DE INPUT VOLTAGE

RANGE

■ LVTTL LOGIC INPUT THRESHOLDS

DESCRIPTION

The ST3293 is a high-speed RS-422 transceiver
with an emphasis circuitry on the driver which
allows reliable long distance communication at
high data rate by reducing inter symbolic
interference. The differential amplitude of the
ST3293 is d igitally programmable in 7 steps
through 3 control pins. The emphasis reduces t he
inter symbolic interference by increasing the
signal am plitude under the micro control and
counteracting the effects of the cab le with the
varying data stream. The ST3293 is a full duplex
device that operates from a single +5V supply. It

ST3293

RS-422 HIGH SPEED TRANSCEIVER

WITH DIGITAL EMPHASIS

SOP

features driver output short circuit current limiting
and an open circuit fail-safe receive r input. The PE
input ca n be used as an emphasis enable. The PE
held LOW disable the emphasis instead set to
HIGH enable the emphasis with the configuration
on C0, C1 and C2 when DI change logic level. The
DI input can direct drive the outputs with a fixed
emphasis or without emphasis as sho w n in the
timing diagram.

ORDERING CODES

Type

ST3293BD -40 to 85 °C SO-14 (Tube) 50 parts per tube / 20 tube per box

ST3293BDR -40 to 85 °C SO-14 (Tape & Reel) 2500 parts per reel

Temperature

Range

Package Comments

1/11January 2003

ST3293

PIN CONFIGURATION

PIN DESCRIPTION

PlN N° SYMBOL NAME AND FUNCTION

1
2 C1 Emphasis Control Input 1
3 C2 Emphasis Control Input 2
4
5 RO Receiver Output
6 DI Driver Input
7 PGND Ground
8 Y Non-inverting Driver Output

9 Z Inverting Driver Output
10 B Inverting Receiver Input
11 A Non-inverting Receiver Input
12 PE Emphasis Enable
13 LGND Ground
14

C0 Emphasis Control Input 0

PV

LV

CC

CC

Supply Voltage

Supply Voltage

TRUTH TABLE
TRANSMITTING INPUTS

INPUTS OUTPUTS

PE DI PECTRL

L X L Disabled
H 0->1 H Enabled
H 1->0 H Enabled

X= Don’t Care; Z=High Impedance

EMPHASIS STATUS

2/11

ST3293

EMPHASIS CONTROL INPUT

INPUTS PE = HIGH DRIVER EMPHASIS FACTOR (DEF)

C0 C1 C2 RL = 100 Ω

LLL 1.0
L L H 1.1
LHL 1.2

L H H 1.3
H L L 1.4
HLH 1.5
H H L 1.6
HHH 1.7

ABSOLUTE MAXIMUM RATINGS

Symbol Parameter Value Unit

V

C0, C1,

C2, DI, PE

Y, Z Driver Output Voltage V
A, B Receiver Input Voltage

RO
PD Continuous Total Power Dissipation (SO-14) 0.5 W

T

T

ESD Human Boby Model (Receiver Inputs vs GND) ±1 KV

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

Supply Voltage

CC

Control Input Voltage

=0VorV

CC

OUT

=Z-state

Receiver Output Voltage -0.5 to (V

Operating Junction Temperature Range

J

Storage Temperature Range

stg

-0.5 to 7 V

-0.5 to 7 V

-0.5 to 7 V

-14 to 14 V
+ 0.5)

CC

-40 to 150 °C

-65 to 150 °C

V

RECOMMENDED OPERATING CONDITIONS

Symbol Parameter Test Conditions Min. Typ. Max. Unit

Supply Voltage 4.75 5.25 V

V

CC

High Level Logic Input Voltage C0, C1, C2, DI, PE 2 V

V

IH

Low Level Logic Input Voltage C0, C1, C2, DI, PE 0 0.8 V

V

IL

I

Input Current of Logic Input C0, C1, C2, DI, PE ±2 µA

IN

Supply Current No Load 4 mA

I

CC

Operating Temperature Range -40 85 °C

T

A

CC

V

3/11

ST3293

DRIVER ELECTRICAL CHARACT ERISTICS

(V

= 5V ± 5%, -40°C < TA< 85°C, unless othe rw ise noted. Typical values are referred to Ta= 25°C)

CC

Symbol Parameter Test Conditions Min. Typ. Max. Unit

|VOD| Differential Output Voltage No Load 2 V

| Differential Output Voltage

|V

OD1

without Emphasis

DPER Differential Output

R=100Ω, PE = Low 2 2.32 2.8 V

See Truth Table 0.9 1.1

Emphasis Step Precision

DEF Differential Output

See Truth Table 1 2

Emphasis Factor

|V

| Differential Driver Output

OPD

with Emphasis

∆V

V

∆V

Change in Magnitude of

OD

Differential Output Voltage
Driver Common-Mode

OC

Output Voltage
Change in Magnitude of

OC

Common Mode Output

R=100Ω, DEF = 1.1 2.52 V
R=100Ω, DEF = 1.7 3.85
R=100Ω, All DEF values -0.2 0 0.2 V

R=100Ω, All DEF values 1 VCC/2 3.5 V

R=100Ω -0.2 0 0.2 V

Voltage

I

OFF

I

OSD

Output Leakage Current
(Y and Z)

Driver Short Circuit Output
Current

VCC= GND VO= 6V 0.1 ±100 µA

VO=0V,

-30 -50 -150 mA

C0 = C1 = C2 = 0

CC

V

RECEIVER DC ELECTRICAL CHARACTERISTICS

= 5V ± 5%, -40°C < TA< 85°C, unless othe rw ise noted. Typical values are referred to Ta= 25°C)

(V

CC

Symbol Parameter Test Conditions Min. Typ. Max. Unit

V

V

V

V

Receiver Differential

TH

Threshold Voltage
Receiver Input Hysteresis VCM=0V 50 mV

HYST

Low Level Output Voltage IOL= 4mA GND 0.2 0.4 mV

OL

High Level Output Voltage IOH= -4mA 3.7 4.7 V

OH

Input Current VIN=10V, Other Input = GND 0.32 1.5 mA

I

IN

Receiver Input Resistance -7V ≤ VCM≤ 7V, VCC=0V 12 24 KΩ

R

IN

-7V ≤ VCM≤ 7V -200 200 mV

CC

V

=10V, Other Input = GND -0.5 -2.5

IN

mV

4/11