EVALPM6680 STMicroelectronics, EVALPM6680 Datasheet - Page 41
EVALPM6680
Manufacturer Part Number
EVALPM6680
Description
BOARD EVALUATION FOR PM6680
Manufacturer
STMicroelectronics
Datasheet
1.PM6680TR.pdf
(49 pages)
Specifications of EVALPM6680
Mfg Application Notes
PM6680 Eval Kit, AN2566 App Note
Main Purpose
DC/DC, Step Down with LDO
Outputs And Type
3, Non-Isolated
Power - Output
13.25W
Voltage - Output
1.05V, 1.5V, 5V
Current - Output
5A, 5A, 100mA
Voltage - Input
6 ~ 28V
Regulator Topology
Buck
Frequency - Switching
200kHz, 300kHz
Board Type
Fully Populated
Utilized Ic / Part
PM6680
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
497-6241
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
PM6680
Figure 39. Inductor current waveforms
Typical components values are: R=47 Ω and C = 1 uF.
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●
●
Figure 40. Bootstrap circuit
The bootstrap circuit capacitor value C
side MOSFET during turn on phase. A typical value is 100nF.
The bootstrap diode D must charge the capacitor during the off time phases. The maximum
rated voltage must be higher than V
A resistor R
node rises up, working like a gate resistor for the turn on phase of the high side MOSFET.
VREF capacitor
A 10 nF to 100 nF ceramic capacitor on VREF pin must be added to ensure noise
rejection.
LDO5 output capacitors
Bypass the output of each linear regulator with 1 uF ceramic capacitor closer to the
LDO pin and a 4.7 uF tantalum capacitor (ESR = 2 Ω). In most applicative conditions a
4.7 uF ceramic output capacitor can be enough to ensure stability.
Bootstrap circuit
The external bootstrap circuit is represented in the next figure:
BOOT
on the BOOT pin could be added in order to reduce noise when the phase
L
L
INmax
BOOT
R
R
.
C
C
C
C
R
R
B
B
B
O
B
O
must provide the total gate charge to the high
O
O
O
O
O
O
T
T
D
D
T
T
B
P
B
P
H
O
H
O
L
A
L
A
O
O
L
L
V
V
D
D
S
S
D
D
T
C
C
T
O
O
E
E
O
O
C
C
5
5
5
5
Device description
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