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Accounting for three things in design: in-rush current limit, 15-Amp max current, and inductive load

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The user is using the LTC7000A as a high-side switch for 4 high-current relays, which require 3.8A for 0.13s and then 0.12A hold current. The design also includes 220uF bulk capacitance that needs gradual charging, and there are concerns about negative voltage spikes due to the inductive nature of the relay coils and long wires. The engineer will discuss the design and address these concerns in a call at 4 PM EST on Monday.
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Category: Hardware
Product Number: LTC7000A

Hello,

I am using the LTC7000A as a high-side switch for 4 high-current relays. These relays use a coil economizer, which requires 3.8 Amps of current for 0.13 seconds, and then a hold current of 0.12 Amps once the relay is closed. 

in addition to this, there is about 220 uF of bulk capacitance that needs to be charged up gradually. 

Last of all, the relay coils are external to my PCB on wires about 300 cm in length, and the relays are inductive. There is a concern about negative voltage spikes. 

Does this design reasonably accommodate for these concerns? Any feedback is appreciated. Thank you!

LTC7000_A_BETSI_RevB_y2026m04d14.asc

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