TPS61160 CTRL pull down resistor

Arne Ansvig

Other Parts Discussed in Thread: DM3725

Currently trying to use the 61160 in EasyScale mode with the DM3725's HDQ/1-wire peripheral.

In the manual for the 61160, SLVS791C, on page 3 in the "Electrical Characteristics" table there is an entry for a "CTRL pull down resistor" R(ctrl).

What is this pull down resistor? Don't we want to pull CTRL high externally when using HDQ/1-wire mode? Or is this something internal to the 61160?

over 13 years ago

0 Avi Chami1 over 13 years ago

Mastermind 7395 points

I agree with you, IMHO it is not clear from the datasheet wether the pulldown is internal or not.

I think that the pulldown is needed, for example, to avoid false operation during processor reset or sleep modes, or in any state where the pin connected to CTRL is in 3state (and could be seen as high by the device, thus enabling it).

The EVM datasheet clearly states that the pulldown is internal to the device:

"Installing this jumper ties the CTRL pin to VIN, and enables the device. Removing the jumper allows the
internal pulldown resistor to pull CTRL to ground, which disables the device. The jumper should be
removed if using an external signal to perform dimming." (page 3), http://www.ti.com/lit/ug/slvu221c/slvu221c.pdf

Hope this helps