2.2 Switching Frequency (FSEL Pin)
In the U2 design, jumper J17 can be used to select between the switching frequency options shown in
.
If the desired option is not available, change one of the resistors to the value which sets the desired option.
In the U1 design, change the FSEL resistor to the value which sets the desired option.
Table 2-2. FSEL Selection
JUMPER SETTING
FSEL RESISTOR
SWITCHING FREQUENCY
1 to 2 pin shorted
17.4 kΩ
750 kHz
3 to 4 pin shorted
11.8 kΩ
1000 kHz
5 to 6 pin shorted
8.06 kΩ
1500 kHz
7 to 8 pin shorted
4.99 kΩ
2200 kHz
(1)
Default Setting
2.3 Current Limit, Soft-Start Time, and Internal Compensation (MODE Pin)
In the U2 design, jumper J18 can be used to select between the current limit, soft-start time, and internal
compensation options shown in
. If the desired option is not available, change one of the resistors to
the value which sets the desired option.
In the U1 design, change the MODE resistor to the value which sets the desired option.
Table 2-3. MODE Selection
JUMPER SETTING
MODE RESISTOR
CURRENT LIMIT
SOFT-START TIME
RAMP
1 to 2 pin shorted
2.21 kΩ
High
1 ms
1 pF
3 to 4 pin shorted
4.87 kΩ
High
1 ms
2 pF
5 to 6 pin shorted
11.3 kΩ
High
1 ms
4 pF
7 to 8 pin shorted
60.4 kΩ
Low
1 ms
2 pF
(1)
Default Setting
2.4 Adjustable UVLO
The undervoltage lockout (UVLO) for U2 can be adjusted externally using R14 (R
ENT
) and R17 (R
ENB
). See the
for detailed instructions for setting the external UVLO.
In the U1 design, the EN pin is floating, so only the internal UVLO of the device is used.
Configurations and Modifications
SLVUBQ1A – AUGUST 2020 – REVISED MAY 2021
TPS543620 SWIFT™ Step-Down Converter Evaluation Module User's Guide
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