TS3300 Datasheet, PDF (11/14 Pages) Touchstone Semiconductor Inc – 0.6-4.5VIN, 1.8-5.25VOUT, 3.5-uA, Low Input Voltage, High-Efficiency Boost + LDO

The output voltage can be set via a voltage divider
circuit as shown in Figure 2. The output feedback
(BO FB) pin is 505mV. It is recommended to use
TS3300
LDO Post-Regulator
The input and output supply voltage range for the
LDO is from 2.3V to 5.25V and 1.8V to 5V,
respectively, where the LDO input is driven by the
output of the boost regulator. The output voltage can
be set via a voltage divider circuit as shown in
Figure 3.
Figure 2: Setting the Boost Output Voltage
with a Voltage Divider
large resistor values to minimize additional current
draw at the output. Resistors values less than 8MΩ
are recommended. Using the following equation to
solve for R1 for a given R2 value, the output voltage
can be set:
R1= ^{ሺVBO - 0.505ሻR2}
0.505
To set a 3V output voltage with R2 = 1.37MΩ, R1 is
calculated to be 6.77MΩ. A 1% standard resistor
value of 6.81MΩ can be selected. This results in an
output voltage of 3.02V.
A shutdown (B^{തതത}E^തതN^ത) pin is also available to shutdown
the boost regulator. The boost regulator is in
shutdown mode when ^തB^തതE^തതN^ത is LOW and supply
current reduces to 0.1µA.
Figure 3: Setting the LDO Output Voltage
with a Voltage Divider
The output feedback (REG FB) pin is 505mV. It is
recommended to use the largest resistor values to
minimize additional current draw at the output. Using
the following equation to solve for R3 for a given R4
value, the output voltage can be set:
R3= ^{ሺVREGOUT - 0.505ሻR4}
0.505
To set a 1.8V output voltage with R4 = 2.61MΩ, R3 is
calculated to be 6.69MΩ. A 1% standard resistor
value of 6.81MΩ can be selected. This results in an
output voltage of 1.82V.
Figure 4: TS3300 LDO FET/Switch Enabled Circuit
TS3300DS r1p0
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RTFDS