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L6932

Multilayer ceramic caps have the lowest ESR and can be required for particular applications. Nevertheless in

several applications they are ok, the loop stability issue has to be considered (see loop stability section).

Below a list of some suggested capacitor manufacturers.

Loop Stability

The stability of the loop is affected by the zero introduced by the output capacitor.

The time constant of the zero is given by:

This zero helps to increase the phase margin of the loop until the time constant is higher than some hundreds

of nsec, depending also on the output voltage and current.

So, using very low ESR ceramic capacitors could produce oscillations at the output, in particular when regulating

high output voltages (adjustable version).

To solve this issue is sufficient to add a small capacitor (e.g. 1nF to 10nF) in parallel to the high side resistor of

the external divider, as shown in figure 9.

Figure 9. Compensation Network

Thermal Considerations

Since the device is housed in a small SO(4+2+2) package the thermal issue can be the bottleneck of many ap-

plications. The power dissipated by the device is given by:

Manufacturer

Type

Cap Value (

µF)

Rated Voltage (V)

PANASONIC

CERAMIC

1 to 47

4 to 16

TAYO YUDEN

CERAMIC

1 to 47

4 to 16

TDK

CERAMIC

1 to 47

4 to 16

TOKIN

CERAMIC

1 to 47

4 to 16

SANYO

POSCAP

1 to 47

4 to 16

PANASONIC

SP

1 to 47

4 to 16

KEMET

TANTALUM

1 to 47

4 to 16

TESR C

OUT

⋅

=

F

ZERO

1

2

π ESR C

OUT

⋅

⋅

--------------------------------------------

=

VOUT=1.2V TO 5V

UP to 2A

VIN=2V TO 14V

C1

OUT

1

3

7

5

6

4

8

2

L6932D1.2

GND

C2

IN

EN

ADJ

R1

R2

C3