Other Parts Discussed in Thread: TPS55288, TPS65987
Hello:
While trying to gauge what one must do in order to satisfy various current limits apparently a Sink side is trying to contract with the USB C PD module, I was looking for a detailed schematic where such a " high precision" current limit is implemented!
And clearly, there is no such schematic given- dare say, even possible!
From the Table in 6.7 "Power Switch" IOCC, what is the meaning of stating " Sink side" contract 1.533 Amp, say at 9 V?
Such limits can be imposed on the BB TPS55288, right?
Per 8.3.3.1.1 in TPS65987 d/s, IOCC limit sets up a "current " source, but how? Other than making the power path switch act in the linear zone, where its power dissipation can and ought to go beyond thermal capabilities, thus leading to failure?...unless TPS55288 is also put in a mode to limit PWM Freq or PW or a combination, to keep lowering Vout ..but this is not mentioned nor clear that TPS65987 should be configured to get into sending I2C commands to track this.
It would seem that designing a pure USV C PD up to 20V , 5amp is not a trivial matter - because implicit in this approach is to have an elaborate Algorithmic flow chart of how TPS55288 AND TPS65987 must be "configured": through I2C to BB stage to provide limit services at the port. Would you not think so?
Any elaboration on this matter will be highly appreciated and speed up our True implementation without gaping holes in its port behaviour.
re
