PM6680ATR STMicroelectronics, PM6680ATR Datasheet - Page 39

• Manufacturer Part Number: PM6680ATR
• Description: IC CTRLR DUAL STEP DOWN 32VFQFPN
• Manufacturer: STMicroelectronics

Specifications of PM6680ATR

• Applications: Controller, Embedded Computer System
• Voltage - Input: 6 ~ 36 V
• Number Of Outputs: 2
• Voltage - Output: 0.9 ~ 5 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 32-VFQFN, 32-VFQFPN
• For Use With: 497-6379 - BOARD EVALUATION FOR PM6680A497-6378 - BOARD EVALUATION FOR PM6680497-6425 - BOARD EVAL BASED ON PM6680A
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6896-2; PM6680ATR

PM6680A
9.7
Other parts design
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Figure 38. VIN pin filter
Typical components values are: R = 3.9 Ω and C = 4.7 µF.
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Figure 39. Inductor current waveforms
Typical components values are: R = 47 Ω and C = 1µF.
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●
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VIN filter
A VIN pin low pass filter is suggested to reduce switching noise. The low pass filter is
shown in the next figure:
VCC filter
A VCC low pass filter helps to reject switching commutations noise:
VREF capacitor
A 10nF to 100nF ceramic capacitor on VREF pin must be added to ensure noise
rejection.
LDO5 output capacitors
Bypass the output of each linear regulator with 1 µF ceramic capacitor closer to the
LDO pin and a 4.7µF tantalum capacitor (ESR = 2 Ω). In most applicative conditions a
4.7 µF ceramic output capacitor can be enough to ensure stability.
Bootstrap circuit
The external bootstrap circuit is represented in the next figure:
Input
voltage
R
R
C
C
R
R
C
C
1
1
0
0
0
0
p
p
F
F
L
V
L
V
V
V
D
D
C
C
I
I
N
N
O
O
C
C
5
5
Design guidelines
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