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FP6373A
High Efficiency 1MHz853AT
Synchronous Step Down Regulator
Description
The FP6373A is a high-efficiency 1MHz synchronous step-down DC-DC regulator and capable of delivering output current up to 3A. The FP6373A operates over wide input voltage range from 2.7V to 5.5V, and integrates main switch and synchronous switch with very low RDS(ON) to minimize the conduction loss. Low output voltage ripple, small external inductor and capacitor sizes are achieved with 1MHz switching frequency.
Pin Assignments
S6 Package (SOT-23-6) FB PG VIN
654 (Marking)
123
EN GND LX
Figure 1. Pin Assignment of FP6373A
Features
2.7V-5.5V Input Voltage Range Adjustable Output Voltage Down to 0.6V Low RDS(ON) for Internal Switch (Top/Bottom):
95/75mΩ 1MHz Switching Frequency Minimizes the
External Components Internal Compensation Function Internal Soft-Start Limits the Inrush Current 100% Dropout Operation Power Good Indicator Output RoHS Compliant and Halogen Free Compact Package: SOT-23-6
Applications
Set Top Box LCD TV Tablet Portable Equipment
Ordering Information
FP6373A□□□
TR: Tape/Reel
C: Green
Package Type S6: SOT-23-6
SOT-23-6 Marking
Part Number FP6373AS6C
Product Code fiV
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Typical Application Circuit
VIN C1
PG
OFF ON
EN VIN
LX
L1
R3 FP6373A
PG FB GND
R1 C3
(opt.)
R2
C2
FP6373A 85T
VOUT
Figure 2. Schematic Diagram
VOUT 3.3V 2.5V 1.8V 1.5V 1.2V 1.05V
C1 10μF MLCC 10μF MLCC 10μF MLCC 10μF MLCC 10μF MLCC 10μF MLCC
R1 453kΩ 316kΩ 200kΩ 150kΩ 100kΩ 75kΩ
R2 100kΩ 100kΩ 100kΩ 100kΩ 100kΩ 100kΩ
L1 2.2μH 2.2μH 1.8μH 1.5μH 1.5μH 1.2μH
Table 1. Recommended Component Values
C2 22μF MLCC x2 22μF MLCC x2 22μF MLCC x2 22μF MLCC x2 22μF MLCC x2 22μF MLCC x2
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Functional Pin Description
FP6373A 85T
Pin Name EN GND LX VIN PG FB
Pin No. 1 2 3 4 5 6
Pin Function
Enable input pin. Pull high to turn on IC, and pull low to turn off IC.
Ground pin.
Inductor pin. Connect an external inductor to this switching node.
Power supply input pin. Placed input capacitors as close as possible from VIN to GND to avoid noise influence.
Open drain power good output pin.
Feedback input pin. Connect this pin to the center point of the output resistor divider (as shown in
Figure 2) to program the output voltage:
0.
1
1 2
.
Block Diagram
PG EN
VIN
Power Good
1MΩ
Enable Control
Undervoltage Lockout
Bias Supply
90% VREF
FB
EA
Compensation
VREF
Soft Start
Slope Compensation
COMP
Control Logic Current Limit
Logic
Control and
Driver Logic
1X
Oscillator
COMP
LX GND
Figure 3. Block Diagram of FP6373A
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FP6373A
Absolute Maximum Ratings (Note 1)
85T
● VIN to GND --------------------------------------------------------------------------------------------------- -0.3V to +6.5V ● LX to GND ---------------------------------------------------------------------------------------------------- -0.3V to (VIN+0.3) ● EN, FB, PG to GND ---------------------------------------------------------------------------------------- -0.3V to VIN ● Junction Temperature Range ---------------------------------------------------------------------------- 150°C ● Lead Temperature (Soldering, 10 sec.) ---------------------------------------------------------------- 260°C ● Storage Temperature Range ----------------------------------------------------------------------------- -65°C to +150℃ ●Package Thermal Resistance, (θJA)
SOT-23-6 ------------------------------------------------------------------------------------------ +250ºC/W ●Package Thermal Resistance, (θJC)
SOT-23-6 ------------------------------------------------------------------------------------------ +110°C/W
Note 1:Stresses beyond those listed under “Absolute Maximum atings" may cause permanent damage to the device.
Recommended Operating Conditions (Note2)
● Supply Input Voltage --------------------------------------------------------------------------------------- 2.7V to 5.5V ● Junction Temperature Range ---------------------------------------------------------------------------- -40°C to +125°C ● Ambient Temperature Range ----------------------------------------------------------------------------- -40°C to +85°C
Note 2:The device is not guaranteed to function outside its operating conditions.
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Electrical Characteristics
(VIN=5V, TA=25°C, unless otherwise specified.)
Parameter
Symbol
Input Voltage Range
VIN
Shutdown Current
ISD
Feedback Reference Voltage
VREF
FB Input Current PFET RON
IFB RDS(ON),P
NFET RON
RDS(ON),N
PFET Current Limit EN Rising Threshold
ILIM VENH
EN Falling Threshold
VENL
Input UVLO Threshold
VUVLO
UVLO Hysteresis
VHYS
Oscillation Frequency
FOSC
Minimum ON Time
Maximum Duty Cycle
PG Rising Threshold PG Sink Current
.