L6731DTR STMicroelectronics, L6731DTR Datasheet - Page 19

• Manufacturer Part Number: L6731DTR
• Description: IC CTRLR ADJ STPDN SYNC 16-TSSOP
• Manufacturer: STMicroelectronics

Specifications of L6731DTR

• Applications: Controller, DDR
• Voltage - Input: 1.8 ~ 14 V
• Number Of Outputs: 1
• Voltage - Output: Adjustable down to 0.6V
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 16-TSSOP Exposed Pad, 16-eTSSOP, 16-HTSSOP
• Output Voltage: 0.6 V to 18 V
• Input Voltage: 1.8 V to 14 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 497-6112-2

L6731D
Figure 11. Compensation network
The compensation network consists in the internal error amplifier, the impedance networks
Z
provide a closed loop transfer function with the highest 0 dB crossing frequency to have
fastest transient response (but always lower than fsw/10) and the highest gain in DC
conditions to minimize the load regulation error. A stable control loop has a gain crossing the
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:
Equation 9
Equation 10
Equation 11
IN
(R3, R4 and C20) and Z
●
●
Modulator singularity frequencies:
Compensation network singularity frequencies:
FB
(R5, C18 and C19). The compensation network has to
ω
ω
P
ω
1
ESR
LC
=
R
=
=
5
ESR
⋅
⎛
⎜ ⎜
⎝
L
C
C
⋅
18
1
Cout
1
1
18
⋅
Cout
+
⋅
C
C
19
19
⎞
⎟ ⎟
⎠
Application details
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