AAT2610_12 Datasheet, PDF (22/31 Pages) Skyworks Solutions Inc. – Seven-Channel PMU for Digital Still Cameras

DATA SHEET
AAT2610
Seven-Channel PMU for Digital Still Cameras
Application Information
Setting the Output Voltage
Step-Down Converter
An external resistor divider is used to program the step-
down converter's output voltage from 0.6V to V_IN.
Resistors R1 and R2 in Figure 1 program the output to
regulate at voltages higher than 0.6V. To limit the bias
current required for the external feedback resistor string
while maintaining good noise immunity, the suggested
value for R2 is 59kΩ. Although a larger value will further
reduce quiescent current, it will also increase the imped-
ance of the feedback node, making it more sensitive to
external noise and interference. Table 1 summarizes the
resistor values for various output voltages with R2 set to
59kΩ.
The AAT2610 has 3 step-down converters: SD1, SD2
and Main SD. The external resistor sets the output volt-
age according to the following equations:
R1
V_OUT = 0.6V · 1 + _R2
R1 =
V_OUT
0.6V
-1
· R2
Table 1 shows the resistor selection for different output
voltage settings. 1% accuracy metal-film resistors are
strongly recommended to get accurate output voltages.
V_OUT (V)
1.2
1.5
1.8
2.5
3.0
3.3
R2 = 59kΩ
R1 (kΩ)
59
88.7
118
187
237
267
Table 1: Resistor Select for Step-Down Converter
Output Voltage Setting.
Step-Up Converter
Similar to the step-down converter, the step-up regula-
tors also use an external resistor divider to program the
output voltage. The AAT2610 has 4 step-up converters:
SU, Main SU, AUX1 and AUX2. The equation for external
resistors setting the output voltage is same as for the
step-down converter. Figure 2 shows the synchronous
(SU and Main SU) and non-synchronous (AUX1 and
AUX2) step-up converter application connections. Table
2 shows resistor selection for different output voltage
settings. 1% accuracy metal-film resistors are strongly
recommended to get accurate output voltages.
V_IN
C1
AAT2610
Step-Down Converter
LX
PV
FB
PG
VOUT
L1
2.5V
R1
C2
187kΩ
R2
59kΩ
Figure 1: Step-Down Converter with Output Voltage Programmed by External Resistor Divider.
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202208A • Skyworks Proprietary Information • Products and Product Information are Subject to Change Without Notice. • July 25, 2012