AS1332 austriamicrosystems AG, AS1332 Datasheet - Page 15

• Manufacturer Part Number: AS1332
• Description: 650mA Step-Down DC-DC Converter
• Manufacturer: austriamicrosystems AG

AS1332
Datasheet - A p p l i c a t i o n I n f o r m a t i o n
External Component Selection
Inductor Selection
For the external inductor, a 3.3µH inductor is recommend. Minimum inductor size is dependant on the desired effi-
ciency and output current. Inductors with low core losses and small DCR at 2MHz are recommended.
Table 6. Recommended Inductors
Capacitor Selection
A 10µF capacitor is recommend for C
recommend as they retain capacitance over wide ranges of voltages and temperatures.
Input and Output Capacitor Selection
Low ESR input capacitors reduce input switching noise and reduce the peak current drawn from the battery. Also low
ESR capacitors should be used to minimize V
have extremely low ESR and are available in small footprints.
For input decoupling the ceramic capacitor should be located as close to the device as practical. A 4.7µF input capaci-
tor is sufficient for most applications. Larger values may be used without limitations.
A 2.2µF to 10µF output ceramic capacitor is sufficient for most applications. Larger values up to 22µF may be used to
obtain extremely low output voltage ripple and improve transient response.
Table 7. Recommended Capacitors for the Step-Down Converter
EN Pin Control
Drive the EN pin using the system controller to turn the AS1332 ON and OFF. Use a comparator, Schmidt trigger or
logic gate to drive the EN pin. Set EN high (>1.2V) for normal operation and low (<0.5V) for a 0.01µA (typ.) shutdown
mode. Set EN low to turn off the AS1332 during power-up and under voltage conditions when the power supply is less
than the 2.7V minimum operating voltage. The part is out of regulation when the input voltage is less than 2.7V.
www.austriamicrosystems.com
LPS4018-222ML_
LPS4018-332ML_
LPS4018-472ML_
GRM21BR61C475KA88
C0603C475K8PAC7867
GRM21BR60J226ME39
GRM188R61C225KE15
GRM21BR60J106KE01
GRM188R61A225KE34
Part Number
Part Number
2.2µH
3.3µH
4.7µH
L
4.7µF
2.2µF
2.2µF
4.7µF
22µF
10µF
IN
C
as well as a 4.7µF for C
0.070Ω
0.080Ω
0.125Ω
DCR
OUT
Voltage
6.3V
6.3V
ripple. Multi-layer ceramic capacitors are recommended since they
16V
16V
10V
10V
Current Rating Dimensions (L/W/T)
Revision 1.01
2.9A
2.4A
1.9A
Type
OUT
X5R
X5R
X5R
X5R
X5R
X5R
. Small-sized X5R or X7R ceramic capacitors are
3.9x3.9x1.7mm
3.9x3.9x1.7mm
3.9x3.9x1.7mm
0805
0805
0805
0603
0603
0603
Size
Murata
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KEMET
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Coilcraft
www.coilcraft.com
Manufacturer
Manufacturer
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