TPS55289: Quiescent current into Vout, clarification needed

Tobias Bucher

Part Number: TPS55289

I'm designing a battery charger with the TPS55289.

The datasheet provides some information about the quiescent current into Vout:

Quiescent current into VOUT pin
IC enabled, no load, no switching, VIN
= 3.0 V, VOUT = 3 V to 20 V, VFB =
VREF + 0.1 V, RFSW = 100 kΩ, TJ up to
125°C
760-860 μA

I take it "IC enabled, no load, no switching" means that the Mode register, OE field is set to "Output disabled"?
Does pulling EN Pin low influence the quiescent current into Vout? If so, how large is Iq when the IC is not enabled?

Your help is appreciated.

Tobias

over 2 years ago

0 Bryce Xun over 2 years ago

TI__Mastermind 27820 points

Hi Tobias,

The quiescent current is the device operation current with no switching, but internal LDO and control circuits are all enabled.

If you pull EN to low, the device would only consume Shutdown current which is 0.8uA typically and 3uA max.

BRs,

Bryce

0 Tobias Bucher over 2 years ago in reply to Bryce Xun

Prodigy 20 points

Hi Bryce

thanks for the quick reply. Just to clarify:

The datasheet only states Iq into Vin if the device isn't enabled. What you are saying is, that if the device is disabled, there is no current at all into Vout (for example if a battery is still connected to Vout)?

Cheers, Tobias

+1 Bryce Xun over 2 years ago in reply to Tobias Bucher

TI__Mastermind 27820 points

Hi Tobias,

Thanks for clarification. The Shutdown current mentioned in datasheet only means the current into Vin when IC is disabled. There would also be current into Vout pin as mentioned which is 1uA typically and 20uA max.

BRs,

Bryce

0 Tobias Bucher over 2 years ago in reply to Bryce Xun

Prodigy 20 points

Hi Bryce

oh...

thanks alot, I feel a bit silly not looking for this in the Output section of the datasheet and not understanding the difference between quiescent current and leakage current.

Best Regards
Tobias

Power management

Power management forum

TPS55289: Quiescent current into Vout, clarification needed