L6725A STMicroelectronics, L6725A Datasheet - Page 21
L6725A
Manufacturer Part Number
L6725A
Description
IC PWM CTLR VOLTAGE MODE SO-16N
Manufacturer
STMicroelectronics
Datasheet
1.L6725ATR.pdf
(32 pages)
Specifications of L6725A
Pwm Type
Voltage Mode
Number Of Outputs
1
Frequency - Max
550kHz
Duty Cycle
100%
Voltage - Supply
4.5 V ~ 18 V
Buck
Yes
Boost
No
Flyback
No
Inverting
No
Doubler
No
Divider
No
Cuk
No
Isolated
No
Operating Temperature
-40°C ~ 85°C
Package / Case
16-SOIC (3.9mm Width)
Frequency-max
550kHz
Output Voltage
0.603 V
Input Voltage
1.8 V to 18 V
Switching Frequency
500 KHz
Operating Temperature Range
- 40 C to + 125 C
Mounting Style
SMD/SMT
Duty Cycle (max)
100 %
Package
SO16N
For Use With
497-5867 - EVAL BOARD 20A 250KHZ L6725497-5500 - EVAL BOARD FOR L6725
Lead Free Status / RoHS Status
Lead free / RoHS Compliant
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
L6725A
Manufacturer:
STMicroelectronics
Quantity:
135
Part Number:
L6725ATR
Manufacturer:
ST
Quantity:
20 000
L6725 - L6725A
Figure 15. Asymptotic Bode plot of Converter's open loop gain
●
●
●
Modulator singularity frequencies:
Compensation network singularity frequencies:
Compensation network design:
–
–
–
–
–
–
Put the gain R
Place
Place
Place
Place
Check the loop gain considering the error amplifier open loop gain.
ω
ω
P
Z
1
1
ω
=
ω
ω
ω
ω
=
LC
Z1
Z2
P1
P2
R
R
5
=
5
before the output filter resonance
at the output filter resonance
at the output capacitor ESR zero
at one half of the switching frequency;
⋅
1
⋅
⎛
⎜ ⎜
⎝
C
C
5
19
C
L
/R
18
1
18
⋅
1
ϖ
Cout
3
+
⋅
in order to obtain the desired converter bandwidth:
C
C
C
(12)
19
=
19
⎞
⎟ ⎟
⎠
R
R
5
3
(8)
(10)
⋅
∆
Vin
Vosc
ω
⋅
ϖ
ω
Z
2
LC
ESR
ω
ω
=
LC
P
=
C
(14)
2
;
ω
ω
20
ESR
=
ESR
LC
⋅
R
(
R
;
4
1
;
1
⋅
3
⋅
1
Cout
C
+
20
R
4
)
(11)
(9)
(13)
Application details
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