Datasheet
Table Of Contents
- FEATURES
- APPLICATIONS
- CONTENTS
- DESCRIPTION
- DEVICE RATINGS
- ABSOLUTE MAXIMUM RATINGS
- RECOMMENDED OPERATING CONDITIONS
- ELECTROSTATIC DISCHARGE (ESD) PROTECTION
- PACKAGE DISSIPATION RATINGS
- ELECTRICAL CHARACTERISTICS
- TYPICAL CHARACTERISTICS
- DEVICE INFORMATION
- BLOCK DIAGRAM
- APPLICATION INFORMATION
- FUNCTIONAL DESCRIPTION
- Voltage Reference
- Oscillator
- Input Undervoltage Lockout (UVLO) and Startup
- Enable and Timed Turn On of the Outputs
- Output Voltage Sequencing
- Soft Start
- Output Voltage Regulation
- Feedback Loop and Inductor-Capacitor (L-C) Filter Selection
- Inductor-Capacitor (L-C) Selection
- Maximum Output Capacitance
- Minimum Output Capacitance
- Modifying The Feedback Loop
- Example: TPS54386 Buck Converter Operating at 12-V Input, 3.3-V Output and 400-mA(P-P) Ripple Current
- Bootstrap for the N-Channel MOSFET
- Light Load Operation
- SW Node Ringing
- Output Overload Protection
- Operating Near Maximum Duty Cycle
- Dual Supply Operation
- Cascading Supply Operation
- Multiphase Operation
- Bypass and FIltering
- Over-Temperature Protection and Junction Temperature Rise
- Power Derating
- PowerPAD Package
- PCB Layout Guidelines
- FUNCTIONAL DESCRIPTION
- DESIGN EXAMPLES
- ADDITIONAL REFERENCES
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BLOCK DIAGRAM
7FB1
+
Soft Start
1
C
COMP
+
S Q
QR
R
+
Current
Comparator
BP
f(I
DRAIN1
) + DC(ofst)
2
1
3
Anti-Cross
Conduction
1.2 MHz
Oscilator
Divide
by 2/4
Ramp
Gen 1
Ramp
Gen 2
CLK1
CLK2
BP
CLK1
Weak
Pull-Down
MOSFET
5EN1
6EN2
6 mA6 mA
VDD2
Internal
Control
10SEQ
150 kW
150 kW
Output
Undervoltage
Detect
BP
FB1
FB2
CLK1
4GND
8FB2
+
Soft Start
2
C
COMP
+
S Q
QR
R
+
Current
Comparator
BP
13
14
12
Anti-Cross
Conduction
BP
CLK2
Weak
Pull-Down
MOSFET
11BP
9ILIM2
150 kW
150 kW
BP
CLK2
4GND
Level
Select
5.25-V
Regulator
References
BOOT1
PVDD1
SW1
BOOT2
PVDD2
SW2
f(I
DRAIN2
) + DC(ofst)
0.8 V
REF
I
MAX2
(Set to one of three limits)
f(I
DRAIN1
)
f(I
MAX1
)
Overcurrent Comp
f(I
SLOPE1
)
Level
Shift
Level
Shift
f(I
DRAIN2
)
f(I
MAX2
)
f(I
SLOPE2
)
FET
Switch
TSD
PVDD2
f(I
SLOPE1
)
f(I
SLOPE2
)
SD1
SD2
UVLO
0.8 V
REF
SD2
0.8 V
REF
SD1
UDG-07124
Overcurrent Comp
R
COMP
R
COMP
TPS54383 , , TPS54386
SLUS774B – AUGUST 2007 – REVISED OCTOBER 2007
Copyright © 2007, Texas Instruments Incorporated Submit Documentation Feedback 11
Product Folder Link(s): TPS54383 TPS54386