mic4723yml Micrel Semiconductor, mic4723yml Datasheet - Page 15
mic4723yml
Manufacturer Part Number
mic4723yml
Description
Mic4723 3a 2mhz Integrated Switch Buck Regulator
Manufacturer
Micrel Semiconductor
Datasheet
1.MIC4723YML.pdf
(20 pages)
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
MIC4723YML
Manufacturer:
MICREL
Quantity:
350
Part Number:
MIC4723YML
Manufacturer:
MICREL/麦瑞
Quantity:
20 000
By looking at the graph, phase margin can be affected to
a greater degree with higher output voltages.
The next bode plot shows the phase margin of a 1.8V
output at 3A without a feedforward capacitor.
Micrel, Inc.
January 2008
50
45
40
35
30
25
20
15
10
5
0
1
Obtainable using C
Max. Amount of Phase Boost
OUTPUT VOLTAGE (V)
2
Voltage
3
FF
V
vs. Output
REF
4
= 1V
5
15
As one can see, the typical phase margin, using the
same resistor values as before without a feedforward
capacitor results in 33.6 degrees of phase margin. Our
prior measurement with a feedforward capacitor yielded
a phase margin of 47 degrees. The feedforward
capacitor has given us a phase boost of 13.4 degrees
(47 degrees- 33.6 Degrees = 13.4 Degrees).
-10
-20
-30
60
50
40
30
20
10
0
100
V
IN
L=1µH
C
R1 = 10k
R2 = 12.4k
C
=3.3V, V
OUT
FF
= 0pF
= 4.7µF
1k
FREQUENCY (Hz)
Bode Plot
OUT
10k
=1.8V, I
PHASE
GAIN
100k
OUT
=3A
1M
M9999-011808-D
210
175
140
105
70
35
0
-35
-70
-105
MIC4723