TPS5103

MULTIPLE MODE SYNCHRONOUS DC/DC CONTROLLER

SLVS240 – SEPTEMBER 1999

27

POST OFFICE BOX 655303

APPLICATION INFORMATION

synchronization

Some applications require switching clock synchronization. Two methods are used for synchronization:

TPS5103

Ct

Rt

740 mV

740 mV

is good for the synchronization between two controllers. If the controller needs to be synchronized with digital

circuit such as DSP, usually the square-type clock signal is used. The configuration exhibited below is for this

type of application:

TPS5103

Ct

Rt

triangle waveform for the controller. Assuming the peak value of the square is known, the resistor and the

capacitor can be adjusted to achieve the correct peak–to–peak value and the offset value.

layout guidelines

Good power supply results will only occur when care is given to proper design and layout. Layout will affect noise

pickup and generation and can cause a good design to perform with less than expected results. With a range

of currents from milliamps to tens or even hundreds of amps, good power supply layout is much more difficult

than most general PCB designs. The general design should proceed from the switching node to the output, then

back to the driver section and, finally, place the low-level components. Below are several specific points to

consider before layout of a TPS5103 design begins.

to Vref5, Vref, INV, LH, and COMP .

plane close to the source of the low-side FET.