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Bosch BIP373 Ignition Driver

VB921's are going out of service, and becoming harder to find, even for bulk purchases. The best replacement for it is the Bosch BIP373, which comes in the same TO220 package and has the same pin-out as the VB921. It has a few features that actually make it better than the VB921:

The Bosch BIP373 ignition module is nearly a drop in replacement for the VB921, with one exception: you must use a mica insulator kit between the BIP373 and heat sink when you mount it because the mounting tab is 'live'.

This part is fairly rare (at the time this is written) and cannot be sourced from Digi-Key, etc., so people wanting them will need to get them from DIYautotune.

The datasheet is here:


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©2008 Bruce Bowling and Al Grippo. All rights reserved. MegaSquirt® and MicroSquirt® are registered trademarks. This document is solely for the support of MegaSquirt® boards from Bowling and Grippo.