LTC3407-3 Linear Technology, LTC3407-3 Datasheet
LTC3407-3
Related parts for LTC3407-3
LTC3407-3 Summary of contents
Page 1
... All other trademarks are the property of their respective owners. Protected by U.S. Patents, including 5481178, 6580258, 6304066, 6127815, 6498466, 6611131. 100k POR RESET 2.2µH V OUT1 SW1 1.8V OUT1 10µF 34073 TA01 LTC3407-3 www.DataSheet4U.com Dual Synchronous, U 3407 dual, constant frequency, synchro- LTC3407-3 Efficiency/Power Loss 100 3.3V OUT 1.8V 0.1 OUT 3.3V 0.01 OUT ...
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... LTC3407 ABSOLUTE AXI U RATI GS (Note 1) V Voltages.................................................– 0. Voltages .................... – 0. OUT1 OUT2 RUN1, RUN2 Voltages ................................ –0. MODE/SYNC Voltage .................................. – 0. SW1, SW2 Voltage ......................... – 0. POR Voltage ................................................– 0. Ambient Operating Temperature Range (Note 2) ....................................... – 40°C to 85°C Junction Temperature (Note 5) ............................. 125° ...
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... OUT I = 80mA TO 800mA LOAD CIRCUIT OF FIGURE 1 Note 3: The LTC3407-3 is tested in a proprietary test mode that connects the output of the error amplifier to an outside servo loop. Note 4: Dynamic supply current is higher due to the internal gate charge being delivered at the switching frequency. Note 5: T ...
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... LTC3407 TYPICAL PERFOR A CE CHARACTERISTICS Reference Voltage vs Temperature 0.615 V = 3.6V IN 0.610 0.605 0.600 0.595 0.590 0.585 –50 – 100 125 TEMPERATURE (°C) 34073 G07 Efficiency 100 95 90 100mA 10mA 85 800mA 80 1mA 1.8V OUT 55 Burst Mode OPERATION ...
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... An internal resistive divider divides the output voltage down for comparison to the internal reference voltage. Exposed Pad (GND) (Pin 11): Power Ground. Connect to the (–) terminal GND, Burst Mode connected to electrical ground on PCB. LTC3407-3 www.DataSheet4U.com to GND and (–) terminal Must be OUT ...
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... LTC3407-3 W BLOCK DIAGRA REGULATOR 1 6 MODE/SYNC + 0. OUT1 – R3 – 0.55V UVDET + + OVDET – 0.65V SHUTDOWN 2 RUN1 0.6V REF OSC 9 RUN2 REGULATOR 2 (IDENTICAL TO REGULATOR 240k 120k FOR CHANNEL 270k 60k FOR CHANNEL OUT2 6 SLOPE COMP EN – SLEEP ...
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... P-channel switch increases with decreasing input supply voltage (See Typical Performance Characteristics). Therefore, the user should calculate the power dissipation when the LTC3407-3 is used at 100% duty cycle with low input voltage (See Thermal Considerations in the Applica- tions Information Section). Low Supply Operation ...
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... The choice of which style inductor to use often depends more on the price vs size requirements and any radiated field/EMI require- ments than on what the LTC3407-3 requires to operate Table 1 shows some typical surface mount inductors that work well in LTC3407-3 applications ...
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... addition, the high Q of ceramic capacitors along with trace inductance can lead to significant ringing. In most cases, 0.1µF to 1µF of ceramic capacitors should also be placed close to the LTC3407-3 in parallel with the ) is deter- main capacitors for high frequency decoupling. OUT V IN ...
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... Connecting this pin to ground selects pulse skipping mode, which provides the lowest output ripple, at the cost of low current efficiency. The LTC3407-3 can also be synchronized to an external 2.25MHz clock signal (such as the SW pin on another LTC3407-3)by the MODE/SYNC pin. During synchroniza- ...
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... The junction temperature RISE )(1 – DC example, consider the case when the LTC3407 dropout on both channels at an input voltage of 2.7V LTC3407-3 www.DataSheet4U.com for both the top and bottom MOSFETs can losses: 2 ...
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... J which is below the absolute maximum junction tempera- ture of 125°C. Design Example As a design example, consider using the LTC3407 portable application with a Li-Ion battery. The battery provides 2.8V to 4.2V. The load requires a maxi- IN mum of 800mA in active mode and 2mA in standby mode. ...
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... Efficiency vs Load Current 100 3.3V OUT 1.8V OUT PULSE SKIP MODE 55 NO LOAD ON OTHER CHANNEL 50 10 100 LOAD CURRENT (mA) 34073 TA02b LTC3407-3 www.DataSheet4U.com IN or GND 100k POWER-ON RESET L1 V OUT1 1.8V 800mA C2 10µF 34073 TA03a 1000 OUT 34073fa 13 ...
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... V OUT2 3.3V 800mA 14 1mm Height Core Supply C1* 10µF RUN2 V RUN1 IN MODE/SYNC POR L2 LTC3407-3 2.2µH SW2 SW1 OUT1 OUT2 10µF GND C1, C2, C3: TAIYO YUDEN JMK212BJ106MD-B L1, L2: COILCRAFT LDO3310-222MX * GREATER THAN 3" FROM POWER SOURCE, ADDITIONAL CAPACITANCE MAY BE REQUIRED. Efficiency vs Load Current ...
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... ALL DIMENSIONS ARE IN MILLIMETERS 4. DIMENSIONS OF EXPOSED PAD ON BOTTOM OF PACKAGE DO NOT INCLUDE MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.15mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 6. SHADED AREA IS ONLY A REFERENCE FOR PIN 1 LOCATION ON THE TOP AND BOTTOM OF PACKAGE LTC3407-3 www.DataSheet4U.com R = 0.115 0.38 ± 0.10 TYP 6 ...
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... Linear Technology Corporation 16 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 2.8V TO 4.2V C1 10µF RUN2 V RUN1 IN MODE/SYNC POR L2 LTC3407-3 D1 10µH SW2 SW1 + M1 C6 47µ OUT1 OUT2 C3 10µF GND C1, C2, C3: TAIYO YUDEN JMK316BJ106ML L1: MURATA LQH32CN2R2M33 C6: SANYO 6TPB47M ...