L6725ATR STMicroelectronics, L6725ATR Datasheet - Page 21

• Manufacturer Part Number: L6725ATR
• Description: IC CTRLR PWM ANTI-DISCHRG 16SOIC
• Manufacturer: STMicroelectronics

Specifications of L6725ATR

• 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: 0.6 V
• Input Voltage: 1.8 V to 18 V
• Operating Temperature Range: - 40 C to + 85 C
• Mounting Style: SMD/SMT
• For Use With: 497-5867 - EVAL BOARD 20A 250KHZ L6725497-5500 - EVAL BOARD FOR L6725
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-5905-2

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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