ISL8013A 查看數據表（PDF） - Intersil
零件编号
产品描述 (功能)
比赛名单
ISL8013A Datasheet PDF : 17 Pages
| |||
ISL8013A
voltage. The ceramic capacitor is recommended to be
X5R or X7R. The recommended X5R or X7R minimum
output capacitor values are shown in Table 1. In Table 1,
the minimum output capacitor value is given for the
different output voltage to make sure that the whole
converter system is stable. Additional output capacitance
should be added for better performances in applications
where high load transient or low output ripple is required.
It is recommended to check the system level
performance along with the simulation model.
TABLE 1. OUTPUT CAPACITOR VALUE vs VOUT
VOUT (V)
0.8
COUT (µF)
2 x 22
L (µH)
1.0~2.2
1.2
2 x 22
1.0~2.2
1.5
2 x 22
1.5~3.3
1.8
2 x 22
1.5~3.3
2.5
2 x 22
1.5~3.3
3.3
2 x 22
2.2~4.7
3.6
2 x 22
2.2~4.7
Output Voltage Selection
The output voltage of the regulator can be programmed
via an external resistor divider that is used to scale the
output voltage relative to the internal reference voltage
and feed it back to the inverting input of the error
amplifier. Refer to Figure 1.
The output voltage programming resistor, R3, will depend
on the value chosen for the feedback resistor and the
desired output voltage of the regulator. The value for the
feedback resistor is typically between 10kΩ and 100kΩ,
as shown in Equation 2.
R3
=
------R----2-----⋅---0---.--8---V--------
VOUT – 0.8V
(EQ. 2)
If the output voltage desired is 0.8V, then R3 is left
unpopulated and R2 is shorted. There is a leakage
current from VIN to LX. It is recommended to preload the
output with 10µA minimum. For better performance, add
47pF in parallel with R2 (100kΩ).
Input Capacitor Selection
The main functions for the input capacitor are to provide
decoupling of the parasitic inductance and to provide
filtering function to prevent the switching current flowing
back to the battery rail. Two 22µF X5R or X7R ceramic
capacitors are a good starting point for the input
capacitor selection.
15
FN7526.0
November 25, 2009
Share Link: 