AN2565 Datasheet, PDF (13/29 Pages) STMicroelectronics – PM6680A evaluation kit dual step-down controller with auxiliary voltages

AN2565
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Jumper settings
Jumper settings
Note:
It is possible to select different working conditions by using the jumpers on the board.
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.
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.
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.
Table 4. Jumper S3 - FSEL pin connections
Position
SMPS OUT1
SGND
200 kHz
SMPS OUT2
300 kHz
VREF
300 kHz
400 kHz
LDO5
400 kHz
500 kHz
To select the switching operation mode of the SMPS, connect the SKIP pin to jumper S10 as
described in Table 5.
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