ltc3406ab-2 Linear Technology Corporation, ltc3406ab-2 Datasheet
ltc3406ab-2
Related parts for ltc3406ab-2
ltc3406ab-2 Summary of contents
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... The internal synchronous switch increases effi ciency and eliminates the need for an external Schottky diode. Low output voltages are easily supported with the 0.6V feedback reference voltage. The LTC3406AB-2 is available in a low profi le (1mm) ThinSOT package. Refer to LTC3406A for applications that require Burst Mode , LT, LTC and LTM are registered trademarks of Linear Technology Corporation ...
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... LTC3406AB-2 ABSOLUTE MAXIMUM RATINGS (Note 1) Input Supply Voltage ....................................– 0. RUN, V Voltages .......................................–0. Voltage (DC) ........................... – 0. P-Channel Switch Source Current (DC) (Note 7) .......................................................800mA N-Channel Switch Sink Current (DC) (Note 7) .....800mA Peak SW Sink and Source Current (Note 7) .............1.3A Operating Temperature Range (Note 2) ...– 40°C to 85°C Maximum Junction Temperature (Notes 3, 6) ....... 125° ...
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... V = 3.6V unless otherwise specifi ed CONDITIONS Note 4: The LTC3406AB-2 is tested in a proprietary test mode that connects V FB Note 5: Dynamic supply current is higher due to the gate charge being delivered at the switching frequency. Note 6: This IC includes overtemperature protection that is intended to protect the device during momentary overload conditions. Junction temperature will exceed 125° ...
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... LTC3406AB-2 TYPICAL PERFORMANCE CHARACTERISTICS (From Figure 1a Except for the Resistive Divider Resistor Values) Oscillator Frequency vs Temperature 2. 3.6V IN 2.45 2.40 2.35 2.30 2.25 2.20 2.15 2.10 2.05 2.00 50 –50 – 100 TEMPERATURE (°C) 3406AB2 G07 R vs Input Voltage DS(ON) 0.40 0.35 0.30 MAIN SWITCH 0.25 SYNCHRONOUS SWITCH 0.20 0.15 0. INPUT VOLTAGE (V) 3406AB2 G10 Dynamic Supply Current ...
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... TO 600mA LOAD V (Pin 4): Main Supply Pin. Must be closely decoupled to IN GND, Pin 2, with a 2.2μF or greater ceramic capacitor. V (Pin 5): Feedback Pin. Receives the feedback voltage FB from an external resistive divider across the output. LTC3406AB-2 Load Step V OUT 100mV/DIV I L 500mA/DIV I LOAD 500mA/DIV ...
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... LTC3406AB-2 FUNCTIONAL DIAGRAM SLOPE COMP OSC FREQ SHIFT 0.6V EA – RUN 0.6V REF 1 SHUTDOWN 6 OSC – SWITCHING RS LATCH BLANKING CIRCUIT 5Ω + – I COMP LOGIC ANTI- AND SHOOT- THRU + I RCMP – GND 3406AB2 BD 3406ab2f ...
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... Typical Performance Characteristics). Therefore, the user should calculate the power dissipation when the , or the beginning RCMP LTC3406AB-2 is used at 100% duty cycle with low input voltage (See Thermal Considerations in the Applications Information section). Slope Compensation and Inductor Peak Current Slope compensation provides stability in constant fre- quency architectures by preventing subharmonic oscil- lations at high duty cycles ...
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... The choice of which style inductor to use often depends more on the price vs size requirements and any radiated fi eld/EMI requirements than on what the LTC3406AB-2 requires to operate. Table 1 shows some typical surface mount inductors that work well in LTC3406AB-2 applications. ...
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... ESR make them ideal for switching regulator applications. Because the LTC3406AB-2’s control loop does not depend on the output capacitor’s ESR for stable operation, ceramic capacitors can be used freely to achieve very low output ripple and small circuit size ...
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... In most applications the LTC3406AB-2 does not dissipate much heat due to its high effi ciency. But, in applications 3406AB2 F02 where the LTC3406AB-2 is running at high ambient tem- perature with low supply voltage and high duty cycles, such as in dropout, the heat dissipated may exceed the maximum junction temperature of the part. If the junction temperature reaches approximately 150° ...
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... A R where T is the ambient temperature example, consider the LTC3406AB-2 in dropout at an input voltage of 2.7V, a load current of 600mA and an ambient temperature of 70°C. From the typical per- formance graph of switch resistance, the R P-channel switch at 70°C is approximately 0.27Ω. There- fore, power dissipated by the part is: ...
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... LTC3406AB-2 APPLICATIONS INFORMATION V OUT Design Example As a design example, assume the LTC3406AB-2 is used in a single lithium-ion battery-powered cellular phone application. The V will be operating from a maximum of IN 4.2V down to about 2.7V. The load current requirement is a maximum of 0.6A but most of the time it will be in standby mode, requiring only 2mA. Effi ciency at both low and high load currents is important ...
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... 2.5V OUT I = 100mA TO 600mA LOAD Figure 5 shows the complete circuit along with its ef- fi ciency curve. V OUT 2.5V 600mA C ** OUT 10µF CER † TAIYO YUDEN JMK212BJ475MG 3406AB2 TA02 3406AB2 TA04 LTC3406AB-2 100 V = 2.5V OUT ...
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... LTC3406AB-2 TYPICAL APPLICATIONS Single Li-Ion 1.2V/600mA Regulator for High Effi ciency and Small Footprint 2.2µ † 22pF C IN 4.7µF LTC3406AB-2 CER RUN V FB 309k GND 309k 3406AB2 TA06 Load Step V OUT 200mV/DIV I L 500mA/DIV I LOAD 500mA/DIV V = 3.6V 20µs/DIV ...
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... S5 Package 5-Lead Plastic SOT-23 (Reference LTC DWG # 05-08-1633 Rev B) 0.95 REF 1.22 REF 1.50 – 1.75 2.80 BSC 1.4 MIN (NOTE 4) PIN ONE 0.95 BSC 0.80 – 0.90 1.00 MAX 0.09 – 0.20 (NOTE 3) LTC3406AB-2 2.90 BSC (NOTE 4) 0.30 – 0.45 TYP 5 PLCS (NOTE 3) 0.01 – 0.10 1.90 BSC S5 TSOT-23 0302 REV B 3406ab2f 15 ...
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... LTC3406AB-2 RELATED PARTS PART NUMBER DESCRIPTION LTC3406A/ 600mA (I ), 1.5MHz, Synchronous Step-Down OUT LTC3406AB DC/DC Converters LTC3407/LTC3407-2 Dual 600mA/800mA (I OUT Synchronous Step-Down DC/DC Converters LTC3410/LTC3410B 300mA (I ), 2.25MHz, Synchronous Step-Down OUT DC/DC Converters LTC3411 1.25A (I ), 4MHz, Synchronous Step-Down OUT DC/DC Converter LTC3412 2. 4MHz, Synchronous Step-Down OUT DC/DC Converter ...