ISO7842: 5v TTL input PWM(Vinl <0.8V, Vinh>2.0V), ISOM7842

Ken Zhang

Part Number: ISO7842
Other Parts Discussed in Thread: ISO7242C, ISO6742-Q1, ISO7741-Q1

Tool/software:

Hi,

A my account is search for a P2P compatible device with NSi8242W-DSWR which supports TTL input signal. The input voltage threshold of ISO7842 is for CMOS, is different, is any new one recommended?

Vcc=5V;

Input PWM signal is 5V TTL;

10 months ago

0 Clemens Ladisch 10 months ago

Guru 318490 points

There are no isolators that are designed for TTL signals with a 5 V supply (edited: except for ISO7xxxC devices). It is assumed that when you have 3.3 V signals, you also use a 3.3 V supply.

0 Ken Zhang 10 months ago in reply to Clemens Ladisch

TI__Expert 3665 points

Clemens

Is there any roadmap to develop digital isolator for TTL signals in BU side? I know that both Chipanalog (www.chipanalog.com) and Novosense are released the isolator for TTL.

0 Aaditya V. 10 months ago in reply to Ken Zhang

TI__Mastermind 18745 points

Hi Ken,

Please allow me to consult my team and respond tomorrow.

Regards,
Aaditya V

0 Aaditya V. 10 months ago in reply to Aaditya V.

TI__Mastermind 18745 points

Hello,

Thank you for your patience.

The ISO7242C is the 25Mbps TTL input digital isolator that TI currently offers. This device supports TTL outputs and supports a supply range of 3.15V to 5.5V. Please find more information on the product page: https://www.ti.com/product/ISO7242C

Regards,
Aaditya V

0 Ken Zhang 9 months ago in reply to Aaditya V.

TI__Expert 3665 points

Aaditya

Creepage >14 (such as iso7842DWW) is needed, but ISO7342's creepage is 8mm and can't meet the requirement in which 1500Vdc is used.

0 Aaditya V. 9 months ago in reply to Ken Zhang

TI__Mastermind 18745 points

Hi Ken,

Thanks for your reply.

The largest creepage isolator we currently offer is the ISO78xxDWW (industrial applications). For automotive applications, we have the ISO7741-Q1 and the ISO6742-Q1 which both have DWW package.

As you already have seen, these are CMOS devices and TI does not currently offer DWW package for TTL inputs.

Regards,
Aaditya

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ISO7842: 5v TTL input PWM(Vinl <0.8V, Vinh>2.0V), ISOM7842