EVALPM6680A STMicroelectronics, EVALPM6680A Datasheet - Page 35
EVALPM6680A
Manufacturer Part Number
EVALPM6680A
Description
EVAL BOARD FOR PM6680A
Manufacturer
STMicroelectronics
Datasheet
1.PM6680ATR.pdf
(48 pages)
Specifications of EVALPM6680A
Mfg Application Notes
PM6680A, AN2565 Appl Note
Main Purpose
DC/DC, Step Down with LDO
Outputs And Type
3, Non-Isolated
Power - Output
10.5W
Voltage - Output
1.8V, 3.3V, 5V
Current - Output
2.5A, 2.5A, 100mA
Voltage - Input
6 ~ 36V
Regulator Topology
Buck
Frequency - Switching
200kHz, 300kHz
Board Type
Fully Populated
Utilized Ic / Part
PM6680A
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Other names
497-6263
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
PM6680A
9.6
Closing the integrator loop
The design of external feedback network depends on the output voltage ripple. If the ripple
is higher than approximately 30 mV, the feedback network (
keep the loop stable.
Figure 36. Circuitry for output ripple compensation
The stability of the system depends firstly on the output capacitor zero frequency.
The following condition should be satisfied:
Equation 23
where k is a design parameter greater than 3 and Rout is the ESR of the output capacitor. It
determinates the minimum integrator capacitor value C
Equation 24
where gm = 50 µs is the integrator transconductance.
OUTPUT
VOLTAGE
Vr
t
COMP PIN
VOLTAGE
D
D
∆
? V
L
L
t
∆
C
C
R
R
? V
C
f
sw
O
O
INT
O
O
U
C
C
U
U
U
>
T
T
T
T
F
F
>
C
R
C
R
k
I
I
L
L
×
I
I
2
I
I
T
T
N
N
N
N
π
f
T
T
T
T
Zout
×
⎛
⎜ ⎜
⎝
f
=
sw
g
k
V
V
m
2
C
C
R
R
C
R
R
C
−
π
O
I
O
I
N
N
2
1
f
2
1
×
O
O
Zout
T
T
M
C
M
U
U
out
F
F
P
k
P
⎞
⎟ ⎟
⎠
T
T
B
B
×
×
INT
V
R
I=gm(V1-Vr)
Vr
OUT
out
:
Figure 36
V
V
r
r
g
g
m
m
+
V
V
1
1
V
V
) is usually enough to
r
r
Design guidelines
+
C
C
-
o
o
m
m
P
P
W
p
W
p
a
a
M
M
r
r
a
a
t
t
o
o
r
r
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