Linear Technology LTC1690 Datasheet

FEATURES

LTC1690

Differential Driver and

Receiver Pair with Fail-Safe

Receiver Output

U

DESCRIPTIO

■

No Damage or Latchup to ±15kV ESD (Human Body
Model), IEC1000-4-2 Level 4 (±8kV) Contact and
Level 3 (±8kV) Air Discharge

■

Guaranteed High Receiver Output State for
Floating, Shorted or Terminated Inputs with No
Signal Present

■

Drives Low Cost Residential Telephone Wires

■

ICC = 600µA Max with No Load

■

Single 5V Supply

■

–7V to 12V Common Mode Range Permits ±7V
Ground Difference Between Devices on the Data Line

■

Power-Up/Down Glitch-Free Driver Outputs Permit
Live Insertion or Removal of Transceiver

■

Driver Maintains High Impedance with the Power Off

■

Up to 32 Transceivers on the Bus

■

Pin Compatible with the SN75179 and LTC490

■

Available in SO, MSOP and PDIP Packages

U

APPLICATIO S

■

Battery-Powered RS485/RS422 Applications

■

Low Power RS485/RS422 Transceiver

■

Level Translator

■

Line Repeater

The LTC®1690 is a low power receiver/driver pair that is
compatible with the requirements of RS485 and RS422.
The receiver offers a fail-safe feature that guarantees a
high receiver output state when the inputs are left open,
shorted together or terminated with no signal present. No
external components are required to ensure the high
receiver output state.

Separate driver output and receiver input pins allow full
duplex operation. Excessive power dissipation caused by
bus contention or faults is prevented by a thermal shut­down circuit which forces the driver outputs into a high
impedance state.

The LTC1690 is fully specified over the commercial and
industrial temperature ranges. The LTC1690 is available in
8-Pin SO, MSOP and PDIP packages.

, LTC and LT are registered trademarks of Linear Technology Corporation.

TYPICAL APPLICATIO

LTC1690 LTC1690

5

Y1

3

D1

2

R1

120Ω

6

Z1

7

B1

120Ω

8

A1

U

120Ω

120Ω

Driving a 1000 Foot STP Cable

8

A2

2

RECEIVER

7

B2

Z2

6

5

Y2

1690 TA01

R2DRIVER

3

D2RECEIVER DRIVER

D1

B2

A2
R2

1690 TA01a

1

LTC1690

1
2
3
4

8
7
6
5

TOP VIEW

MS8 PACKAGE

8-LEAD PLASTIC MSOP

V

CC

R
D

GND

A
B
Z
Y

WW

W

ABSOLUTE MAXIMUM RATINGS

U

(Note 1)

Supply Voltage (VCC) .............................................. 6.5V

Driver Input Voltage..................... –0.3V to (VCC + 0.3V)

Driver Output Voltages ................................. –7V to 10V

Receiver Input Voltages ......................................... ±14V

Receiver Output Voltage .............. –0.3V to (VCC + 0.3V)

Junction Temperature........................................... 125°C

U

W

PACKAGE/ORDER INFORMATION

ORDER PART

NUMBER

LTC1690CMS8

T

JMAX

= 125°C, θ

= 200°C/W

JA

MS8 PART MARKING

LTDA

Operating Temperature Range

LTC1690C ........................................ 0°C ≤ TA ≤ 70°C

LTC1690I..................................... – 40°C ≤ TA ≤ 85°C

Storage Temperature Range ................. –65°C to 150°C

Lead Temperature (Soldering, 10 sec).................. 300°C

U

ORDER PART

V

1

CC

R

2

D

3

GND

4

S8 PACKAGE

8-LEAD PLASTIC SO

T

= 125°C, θ

JMAX

= 125°C, θ

T

JMAX

TOP VIEW

R

D

N8 PACKAGE

8-LEAD PLASTIC DIP

= 130°C/W (N)

JA

= 135°C/W (S)

JA

A

8

B

7

Z

6

Y

5

NUMBER

LTC1690CN8
LTC1690IN8
LTC1690CS8
LTC1690IS8

S8 PART MARKING

1690
1690I

DC ELECTRICAL CHARACTERISTICS

Consult factory for Military Grade Parts

The ● denotes the specifications which apply over the full operating

temperature range, otherwise specifications are at T

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

V

OD1

V

OD2

V

OD3

∆V

V

OC

∆|VOC| Change in Magnitude of Driver Common Mode R = 22Ω, 27Ω or 50Ω, Figure 1 ● 0.2 V

V

IH

V

IL

I

IN1

I

IN2

V

TH

∆V

2

Differential Driver Output Voltage (Unloaded) IO = 0 ● V
Differential Driver Output Voltage (with Load) R = 50Ω; (RS422) ● 2V

Differential Driver Output Voltage (with Common Mode) V
Change in Magnitude of Driver Differential Output R = 22Ω, 27Ω or 50Ω, Figure 1 ● 0.2 V

OD

Voltage for Complementary Output States V
Driver Common Mode Output Voltage R = 22Ω, 27Ω or 50Ω, Figure 1 ● 3V

Output Voltage for Complementary Output States
Input High Voltage Driver Input (D) ● 2V
Input Low Voltage Driver Input (D) ● 0.8 V
Input Current Driver Input (D) ● ±2 µA
Input Current (A, B) VCC = 0V or 5.25V, VIN = 12V ● 1mA

Differential Input Threshold Voltage for Receiver –7V ≤ VCM ≤ 12V ● –0.20 –0.01 V
Receiver Input Hysteresis VCM = 0V ±30 mV

TH

= 25°C. VCC = 5V ±5% (Notes 2, 3)

A

R = 22Ω or 27Ω; (RS485), Figure 1

= –7V to 12V, Figure 2 1.5 5 V

TST

= –7V to 12V, Figure 2

TST

= 0V or 5.25V, VIN = –7V ● –0.8 mA

V

CC

CC

● 1.5 5 V

V

LTC1690

DC ELECTRICAL CHARACTERISTICS

temperature range, otherwise specifications are at T

= 25°C. VCC = 5V ±5% (Notes 2, 3)

A

The ● denotes the specifications which apply over the full operating

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

V

OH

V

OL

R

IN

I

CC

I

OSD1

I

OSD2

I

OZ

I

OSR

t

PLH

t

PHL

t

SKEW

tr, t
t

PLH

t

PHL

t

SKD

f

MAX

Note 1: Absolute Maximum Ratings are those values beyond which the life
of the device may be impaired.

Receiver Output High Voltage IO = –4mA, VID = 200mV ● 3.5 V
Receiver Output Low Voltage IO = 4mA, VID = –200mV ● 0.4 V
Receiver Input Resistance –7V ≤ VCM ≤ 12V ● 12 22 kΩ
Supply Current No Load ● 260 600 µA
Driver Short-Circuit Current, V
Driver Short-Circuit Current, V

= HIGH –7V ≤ VO ≤ 10V 35 250 mA

OUT

= LOW –7V ≤ VO ≤ 10V 35 250 mA

OUT

Driver Three-State Current (Y, Z) –7V ≤ VO ≤ 10V, VCC = 0V ● 5 200 µA
Receiver Short-Circuit Current 0V ≤ VO ≤ V
Driver Input to Output, Figure 3, Figure 4 R
Driver Input to Output, Figure 3, Figure 4 R
Driver Output to Output, Figure 3, Figure 4 R
Driver Rise or Fall Time, Figure 3, Figure 4 R

f

Receiver Input to Output, Figure 3, Figure 5 R
Receiver Input to Output, Figure 3, Figure 5 R
|t

– t

PLH

|, Differential Receiver Skew, Figure 3, Figure 5 R

PHL

Maximum Data Rate, Figure 3, Figure 5 R

CC

= 54Ω, CL1 = CL2 = 100pF ● 10 22.5 60 ns

DIFF

= 54Ω, CL1 = CL2 = 100pF ● 10 25 60 ns

DIFF

= 54Ω, CL1 = CL2 = 100pF ● 2.5 15 ns

DIFF

= 54Ω, CL1 = CL2 = 100pF ● 21340 ns

DIFF

= 54Ω, CL1 = CL2 = 100pF ● 30 94 160 ns

DIFF

= 54Ω, CL1 = CL2 = 100pF ● 30 89 160 ns

DIFF

= 54Ω, CL1 = CL2 = 100pF 5 ns

DIFF

= 54Ω, CL1 = CL2 = 100pF ● 5 Mbps

DIFF

● 785mA

Note 2: All currents into device pins are positive; all currents out of device
pins are negative. All voltages are referenced to device ground unless
otherwise specified.

Note 3: All typicals are given for V

= 5V and TA = 25°C.

CC

UW

TYPICAL PERFOR A CE CHARACTERISTICS

Receiver Input Threshold Voltage
(Output High) vs Temperature

0
–20
–40
–60
–80

–100
–120
–140
–160
–180

RECEIVER INPUT THRESHOLD VOLTAGE (mV)

–200

–55 –35 –15 5 25 45 65 85 105 125

VCM = 12V

VCM = 0V

VCM = –7V

TEMPERATURE (°C)

VCC = 5V

1690 G01

Receiver Input Threshold Voltage
(Output Low) vs Temperature

0

VCC = 5V

–20
–40
–60

–80
–100
–120
–140
–160
–180

RECEIVER INPUT THRESHOLD VOLTAGE (mV)

–200

–55 –35 –15 5 25 45 65 85 105 125

VCM = 12V

VCM = 0V

VCM = –7V

TEMPERATURE (°C)

1690 G02

Receiver Hysteresis vs
Temperature

100

VCC = 5V

90
80
70
60

VCM = 0V

50
40
30
20

RECEIVER HYSTERESIS (mV)

10

VCM = –7V

0

–55 –35 –15 5 25 45 65 85 105 125

VCM = 12V

TEMPERATURE (°C)

1690 G03

3

LTC1690

UW

TYPICAL PERFOR A CE CHARACTERISTICS

Receiver Input Offset Voltage vs
Temperature

0

VCC = 5V

–20
–40
–60

–80
–100
–120
–140
–160
–180

RECEIVER INPUT OFFSET VOLTAGE (mV)

–200

–55 –35 –15 5 25 45 65 85 105 125

VCM = 0V

VCM = –7V

VCM = 12V

TEMPERATURE (°C)

Receiver Output Low Voltage vs
Output Current

40

TA = 25°C

35

= 4.75V

V

CC

30

25

20

15

10

RECEIVER OUTPUT CURRENT (mA)

5

0

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2

RECEIVER OUTPUT LOW VOLTAGE (V)

1690 G04

1690 G07

Receiver Input Threshold Voltage
vs Supply Voltage

–40

TA = 25°C

–60

–80

–100

–120

–140

RECEIVER INPUT THRESHOLD VOLTAGE (mV)

–160

4.5 4.75 5 5.25 5.5

OUTPUT HIGH

OUTPUT LOW

SUPPLY VOLTAGE (V)

Receiver Output High Voltage vs
Temperature

4.8
I = 8mA

4.6
V

= 4.75V

CC

4.4

4.2

4.0

3.8

3.6

3.4

3.2

RECEIVER OUTPUT HIGH VOLTAGE (V)

3.0

–55 –35 –15 5 25 45 65 85 105 125

TEMPERATURE (°C)

1690 G05

1690 G08

Receiver Output High Voltage vs
Output Current

–25

TA = 25°C
V

= 4.75V

CC

–20

–15

–10

–5

RECEIVER OUTPUT CURRENT (mA)

0

4.5 4 3

5

RECEIVER OUTPUT HIGH VOLTAGE (V)

3.5

Receiver Output Low Voltage vs
Temperature

0.7
I = 8mA

= 4.75V

V

0.6

CC

0.5

0.4

0.3

0.2

0.1

RECEIVER OUTPUT LOW VOLTAGE (V)

0

–55 –35 –15 5 25 45 65 85 105 125

TEMPERATURE (°C)

2.5

2

1690 G06

1690 G09

Receiver Propagation Delay vs
Temperature

120

VCC = 5V

110

100

90

80

70

RECEIVER PROPAGATION DELAY (ns)

60

–55 –35 –15 5 25 45 65 85 105 125

t

PLH

t

PHL

TEMPERATURE (°C)

4

1690 G10

Receiver Skew t

PLH

– t

PHL

Temperature

10

9

8

7

6

5

RECEIVER SKEW (ns)

4

3

2

–55 –35 –15 5 25 45 65 85 105 125

TEMPERATURE (°C)

VCC = 5V

 vs

1690 G11

Receiver Propagation Delay vs
Supply Voltage

110

100

90

80

70

60

RECEIVER PROPAGATION DELAY (ns)

50

4.5 4.6 4.7 4.8 4.9 5 5.1 5.2 5.3 5.4 5.5

t

PLH

t

PHL

SUPPLY VOLTAGE (V)

1690 G12