ADuM1253

Ultra-Low-Power, I2C Isolator with

Unidirectional SCL, Extended VDD,

Idle-Bus Hot-Swap, and Low VOL

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Analog Devices | 9

Timing Diagrams

VDD1

0.1µF

VDD1

TEST

SOURCE

S__1

GND1

GND2

VDD2

0.1µF

VDD2

S__2

ADuM1253

R1

CL1

CL2

R2

Figure 1. Timing Test Diagram

VDD2

S__2

GND2

50%

50%

tPLH21

tPHL21

VDD1

S__1

GND1

90%

0.9V

tF1

70%

VDD1

S__1

GND1

50%

50%

tPLH12

tPHL12

VDD2

S__2

GND2

70%

0.4V

tF2

90%

10%

Figure 2. Timing Parameter Definition

Safety Limits

Damage to the IC can result in a low-resistance path to ground or to the supply and, without current limiting, the

ADuM1253 can dissipate excessive amounts of power. Excessive power dissipation can damage the die and result in

damage to the isolation barrier, potentially causing downstream issues. The safety limits for the ADuM1253 are listed in

the package specific Isolation Characteristics table.

The maximum safety temperature (TS) for the device is the +150°C maximum junction temperature specified in the

Absolute Maximum Ratings. See the Thermal Considerations section for details on determining the junction temperature.

Figure 3 and Figure 4 show the thermal derating curves for safety limiting the power and the current for the device in the

8-lead Narrow SOIC (21-0041) package when mounted on the JEDEC 2S2P test card. Ensure that the junction

temperature does not exceed +150°C.