L6730 STMicroelectronics, L6730 Datasheet - Page 36

• Manufacturer Part Number: L6730
• Description: IC CTRLR ADJ STPDN SYNC 20-TSSOP
• Manufacturer: STMicroelectronics
• Type: Step-Down (Buck)r

Specifications of L6730

• Internal Switch(s): No
• Synchronous Rectifier: Yes
• Number Of Outputs: 1
• Voltage - Output: Adj to 0.6V
• Frequency - Switching: 100kHz ~ 1MHz
• Voltage - Input: 1.8 ~ 14 V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 20-TSSOP Exposed Pad, 20-eTSSOP, 20-HTSSOP
• Output Voltage: 0.6 V
• Input Voltage: 1.8 V to 14 V
• Mounting Style: SMD/SMT
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• For Use With: 497-5868 - EVAL BOARD 30A 400KHZ L6730497-5501 - EVAL BOARD FOR L6730XX
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Power - Output: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 497-5291-5

Application details
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0 dB axis with -20 dB/decade slope and a phase margin greater than 45°. To locate poles
and zeroes of the compensation networks, the following suggestions may be used:
●
●
●
Figure 30. Asymptotic bode plot of converter's open loop gain
Modulator singularity frequencies:
Compensation network singularity frequencies:
Compensation network design:
–
–
–
–
–
–
Put the gain R
Place ω
Place ω
Place ω
Place ω
Check the loop gain considering the error amplifier open loop gain.
ω
Z1
Z2
P1
P2
ω
P
1
ω
LC
before the output filter resonance ω
at the output filter resonance ω
at the output capacitor ESR zero ω
at one half of the switching frequency;
=
Z
1
R
=
=
5
5
/R
⋅
⎛
⎜ ⎜
⎝
R
L
3
C
5
C
⋅
1
⋅
in order to obtain the desired converter bandwidth
1
18
Cout
1
18
C
ϖ
Doc ID 11938 Rev 3
+
19
⋅
C
C
C
=
19
19
R
R
⎞
⎟ ⎟
⎠
(17)
5
3
(13)
⋅
Δ
(15)
Vin
Vosc
ω
Z
⋅
ω
ϖ
2
ω
ESR
LC
=
P
2
C
=
LC
=
20
(18)
ESR
;
R
⋅
(
4
ESR
LC
R
1
⋅
1
C
3
1
⋅
;
+
Cout
20
;
R
4
)
(16)
(14)
(18)
L6730 - L6730B