Transceivers with ±15kV ESD Protection

14

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Test Circuits

Y

Z

Figure 1. Driver DC Test Load

DI

DE

HIGH

Y

Z

GND

GND2

Figure 2. Driver Timing Test Circuit

TGM-240

1/2

BAT54C

TRANSFORMER

DRIVER

BARRIER

TRANSCEIVER

ISOLATION BARRIER

BARRIER

TRANSCEIVER

1/2

BAT54C

VOLTAGE

REGULATOR

GND2

+3.0V TO +5.5V

DRIVER

RECEIVER

A

B

Y

Z

SLO

RO2

ST1

RO1

RE

DE

DI

GND1

ST2

0.1

µF

0.1

µF

CONTROL GROUND

RS485 GROUND

10

µF

10

µF

MAX3535E

Figure 5. Self-Oscillating Configuration

500

Ω

Y/Z

GND2

500

Ω

Figure 3. Driver Timing Test Load

1k

Ω

RO1/RO2

GND1/GND2

1k

Ω

Figure 4. Receiver Timing Test Load