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TP3406
1.5MHz, 600mA, High Efficiency PWM Step-Down DC/DC Converter
General Description
The TP3406 is a high-efficiency pulse-width-modulated(PWM) step-down DC-DC converter. Capable of delivering600mA output current over a wide input voltage range from2.5V to 5.5V, the TP3406 is ideally suited for port -ableelectronic devices that are powered from 1-cell Li-ion battery or from other power sources within the range suchas cellular phones, PDAs and handy-terminals. Internal synchronous rectifier with low RDS(ON) dramatically reduces cond -uction loss at PWM mode. No external Schottky diode is required in prac -tical application. The TP3406 automatically turns off the synchronous rec -tifier while the inductor current is low and enters discontinuous PWM mode. This can increase efficiency at light load condition. The TP3406 enters Low-Dropout mode when normal PWM cannot provide regulated output voltage by continuously turning on the upper P-MOSFET. TP3406 enter shutdown mode and consumes less than 0.1mA when EN pin is pulled low. The switching ripple is easily smoothed-out by small package filtering elem -ents due to a fixed operation frequency of 1.5MHz. This along with small SOT-23-5 and TSOT-23-5 package provides small PCB area application. Other features include soft start, lower internal reference voltage with 2% accuracy, over temperature protection,and over current protection
Pin Configurations
Features
+2.5V to +5.5V Input Range Adjustable Output From 0.6V to VIN 1.0V, 1.2V, 1.5V, 1.8V, 2.5V and 3.3V Fixed/ Adjustable Output Voltage 600mA Output Current, 1A Peak Current 95% Efficiency
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No Schottky Diode Required 1.5MHz Fixed-Frequency PWM Operation Small SOT-23-5 and TSOT-23-5 Package RoHS Compliant and 100% Lead (Pb)-Free
Applications
Cellular Telephones Personal Information Appliances Wireless and DSL Modems MP3 Players Portable Instruments
Typical Application Circuit
TP3406
Figure 1. Fixed Voltage Regulator
Figure 2. Adjustable Voltage Regulator
with R2 = 300kΩ to 60kΩ so the IR2 = 2μA to 10μA, and (R1 x C1) should be in the range between 3x10-6 and 6x10-6 for component selection.
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Functional Pin Description
TP3406
Pin Number Pin Name
1 EN 2 GND 3 LX 4 VIN 5 FB/VOUT
Pin Function
Chip Enable (Active High, do not leave EN pin floating, and VEN < VIN + 0.6V> Ground. Pin for Switching. Power Input. Feedback Input Pin.
Function Block Diagram
Absolute Maximum Ratings (Note 1)
Supply Input Voltage ----------------------------------------------------------------------- 6.5V Enable, FB Voltage-------------------------------------------------------------------------- VIN + 0.6V Power Dissipation, PD @ TA = 25°C SOT-23-5, TSOT-23-5 ------------------------------------------------------------------------ 0.4W Package Thermal Resistance (Note 4) SOT-23-5, TSOT-23-5, θJA ------------------------------------------------------------------- 250°C/W SOT-23-5, TSOT-23-5, θJC ------------------------------------------------------------------- 130°C/W Junction Temperature Range ------------------------------------------------------------- 150°C Lead Temperature (Soldering, 10 sec.) ------------------------------------------------ 260°C
Storage Temperature Range -------------------------------------------------------------- −65°C to 150°C
ESD Susceptibility (Note 2) HBM (Human Body Mode) -------------------------------------------------------------------- 2kV MM (Machine Mode) ---------------------------------------------------------------------------- 200V
Recommended Operating Conditions (Note 3)
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TP3406
Supply Input Voltage ------------------------------------------------------------------------- 2.5V to 5.5V Junction Temperature Range -------------------------------------------------------------- −40°C to 125°C
Ambient Temperature Range -------------------------------------------------------------- −40°C to 85°C
Electrical Characteristics
(VIN = 3.6V, VOUT = 2.5V, VREF = 0.6V, L = 2.2μH, CIN = 4.7μF, COUT = 10μF, TA = 25°C, IMAX = 600mA unless
otherwise specified)
Parameter
Symbo Test Conditions
Min Typ Max Units
l
Input Voltage Range
VIN
2.5 5.5 V
Quiescent Current
IQ IOUT = 0mA, VFB = VREF + 5%
50 100 μA
Shutdown Current
ISHDN EN = GND
0.1 1 μA
Reference Voltage
VREF For adjustable output voltage 0.588 0.6 0.612
V
Adjustable Output Range VOUT
VREF
VIN−0.2 V
Output Voltage Accuracy
Fix ΔVOUT Adjustable ΔVOUT
VIN = 2.2 to 5.5V, VOUT = 1.0V 0A < IOUT < 600mA VIN = 2.2 to 5.5V, VOUT = 1.2V 0A < IOUT < 600mA VIN = 2.2 to 5.5V, VOUT = 1.5V 0A < IOUT .