AN2565

Jumper settings

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Jumper settings

It is possible to select different working conditions by using the jumpers on the board.

Note:

Jumpers S1, S12 and S13 are already soldered on the evaluation board and it is not

necessary to change them. Please refer to the schematic to verify their proper connection.

The external bypass connections for the linear regulator LDO5 are set by connecting the

V5SW pin to jumper S11 as indicated in Table 3 below.

The FSEL pin is connected to jumper S3 to select the SMPS frequency. The jumper

positions and corresponding frequencies are shown in Table 4 below.

To select the switching operation mode of the SMPS, connect the SKIP pin to jumper S10 as

described in Table 5.

Table 3.

Jumper S11 - V5SW pin connections

Position

LDO5 working conditions

OUT5V

When the main output voltage is greater than the boostrap-switchover

threshold, an internal 3

Ω (max) P-channel MOSFET switch connects the

V5SW pin to the LDO5 pin, shutting down the LDO5 internal linear

regulator. If not used, it must be tied to ground.

SGND

The internal linear regulator LDO5 is always on. In this case, LDO5

supplies all gate drivers and the internal circuitry. It can provide an output

peak current of 100 mA.

EXT5V

The internal linear regulator LDO5 remains off if an alternative 5 V external

voltage is applied to the EXT5V test point. An internal 3

Ω(max) P-channel

MOSFET switch connects the V5SW pin to the LDO5 output. The gate

drivers and internal circuitry are supplied by the same 5 V external voltage

applied.

Table 4.

Jumper S3 - FSEL pin connections

Position

SMPS OUT1

SMPS OUT2

SGND

200 kHz

300 kHz

VREF

300 kHz

400 kHz

LDO5

400 kHz

500 kHz