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Preliminary Datasheet
LP6343
1.5MHz, 3A Step-down Converter With Soft-Start
General Description
The LP6343 contains a independent 1.5MHz constant frequency, current mode, PWM step-down converters. The converter integrates a main switch and a synchronous rectifier for high efficiency without an external Schottky diode. The LP6343 is ideal for powering portable equipment that runs from a single cell Lithium-Ion (Li+) battery. The converter can supply 3000mA of load current from a 2.5V to 5.5V input voltage. The output voltage can be regulated as low as 0.6V. The LP6343 can also run at 100% duty cycle for low dropout applications. The LP6343 is available in a 10-lead 3mm*3mm TDFN-10 and EMSOP-10 package and is rated over the -40°C to 85°C temperature range.
Order Information
LP6343□ □ □ □
F: Pb-Free
Package Type QV: TDFN-10 MS: MSOP-10(E) Output type A: Adjustable
Typical Application Circuit
Features
Input Voltage Range: 2.5V to 5.5V Output Voltage Range: 0.6V to VIN 3000mA Load Current on Channel Up to 95% Efficiency 100% Duty Cycle in Dropout < 1 u A Quiescent Current 1.5MHz Switching Frequency Soft star Function Short Circuit Protection Current Mode Operation Thermal Fault Protection 3 m m × 3 m m TDFN-10 or MSOP-10 Package RoHS Compliant and 100% Lead (Pb)-Free
Applications
Portable Media Players Cellular and Smart mobile phone PDA/DSC
GPS Applications
Marking Information
Please see website. www.lowpowersemi.com
VIN_5V 22uF
AGND PGND PGND
LP6343AQVF
1 2 3
EN Vin Vin
4 PGOOD
SW 7 SW 8
2.2uH 22pF
FB 5
Vout=(R1/R2+1)*0.6V
3.3V/3A R1 45K
22uF*2
R2 10K
6 9 10
LP6343 –00 Version 1.0 Datasheet
Feb.-2010
www.lowpowersemi.com
Page 1 of 12
Preliminary Datasheet
Functional Pin Description
MSOP10
EN 1 VIN 2 VIN 3 PGOOD 4 FB 5
EP
10 PGND 9 PGND 8 SW 7 SW 6 AGND
DFN10
EN 1 VIN 2 VIN 3 PGOOD 4 FB 5
10 PGND 9 PGND EP 8 SW 7 SW 6 AGND
LP6343
Pin Description
Pin NO 1
2, 3 4
5
7, 8 6,9,10
11
PIN EN Vin PGOOD
DESCRIPTION
Enable Control Input. Drive EN1 above 1.5V to turn on the Channel. Drive EN below 0.4V to turn it off (shutdown current < 0.1µA).
Supply Input.
Power Good Open Drain Output. Connects a 100kΩ pull up resistor between VIN and this pin to obtain a PGOOD voltage. Connect this pin to AGND if not used.
FB
Feedback Input. Connect FB to the center point of the external resistor divider. Normal voltage for this pin is 0.6V.
SW
Switch Mode Connection to Inductor. This pin connects to the drains of the internal main and synchronous power MOSFET switches.
AGND/PGND Ground.
EP Exposed PAD - must connect to Ground
Function Block Diagram
LP6343 –00 Version 1.0 Datasheet
Feb.-2010
www.lowpowersemi.com
Page 2 of 12
Preliminary Datasheet
LP6343
Absolute Maximum Ratings
Input Voltage to GND ------------------------------------------------------------------------------------------- 6V SW to GND (VSW) ---------------------------------------------------------------------------- 0.3V to VIN +0.3V FB to GND (VFB) ------------------------------------------------------------------------------ 0.3V to VIN +0.3V EN EN_BAT to GND (VEN) ------------------------------------------------------------------------0.3V to 6V Operating Junction Temperature Range (TJ) ----------------------------------------------------40℃ to 150℃
Maximum Soldering Temperature (at leads, 1 0sec) ----------------------------------------------------- 260℃
Electrical Characteristics
(VIN =VEN,Typical values are TA=25℃ )
Symbol VIN VFB
△VOUT
△VFB VOUT
IQ ISHDN ILIM IPK RDS(ON)H RDS(ON)L
ILXLEAK ΔVLine-reg/ΔVIN IFB FOSC TS TSD
THYS VEN(L) VEN(H) IEN
Parameter Input Voltage
Conditions
Min. 2.5
Feedback Threshold Voltage Accuracy
VFB, TA=25°C VFB, TA= -40°C ~+85°C
Output Voltage Line Regulation
Reference Voltage Line Regulation
ILOAD = 0 VINB = 2.5V to 5.5V
VINB = 2.5V to 5.5V
Output Voltage Range
0.588 0.582
0.6
Quiescent Current
Active, VFB =0.5V,VIN= VEN PSM,VFB =0.7V,VIN= VEN
Shutdown Current
VEN =0V
P-Channel Current Limit
Peak Inductor Current
VFB =0.5V
High-Side Switch On Resistance
Low-Side Switch On Resistance
LX Leakage Current
Line Regulation FB Leakage Current Oscillator Frequency
VEN=0V, VSW=0 or 5V, VIN=5V
VIN = 2.8V to 5.5V
VOUT = 1 .0V VFB =0V
1.2
Startup Time
Over-Temperature Shutdown Threshold Over-Temperature Shutdown Hysteresis
Enable Threshold Low
From Enable to Output Regulation
Enable Threshold High Input Low Current
VIN = VEN = 5.5V
0.3 -1
LP6343 Typ.
0.6 0.6 0.04 0.04
170 80 1 3.8 3.5 135 130
0.2 30 1.5 120 150 20
1.0
Max. 5.5 0.612 0.618 0.4 0.4 VINB
1 0.4 1.8
0.4 1.5
1
Unit V V
%/v %/v
V µA µA µA A A m m
µA
%/V nA MHz µs
℃
℃
V V µA
Note: Output Voltage: Vout = 0.6 X (1+R2/R1) Volts;
LP6343 –00 Version 1.0 Datasheet
Feb.-2010
www.lowpowersemi.com
Page 3 of 12
Preliminary Datasheet Typical Operating Characteristics
LP6343
LP6343 –00 Version 1.0 Datasheet
Feb.-2010
www.lowpowersemi.com
Page 4 of 12
Prelimina.