LTC3407 Linear Technology Corporation, LTC3407 Datasheet
LTC3407
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LTC3407 Summary of contents
Page 1
... In shutdown, the device draws <1µA. The LTC3407-4 is identical to the LTC3407-2 except for the reduced power-on reset delay time. , LT, LTC, LTM and Burst Mode are registered trademarks of Linear Technology Corporation ...
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... Ambient Operating Temperature Range (Note 2) ....................................... – 40°C to 85°C + 0.3V IN Junction Temperature (Note 5) ............................. 125°C IN Storage Temperature Range ................. – 65°C to 125°C IN Lead Temperature (Soldering, 10 sec) + 0.3V IN LTC3407-4EMSE only ...................................... 300°C Reflow Peak Body Temperature ............................ 260° FB2 9 RUN2 8 POR 7 ...
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... CONDITIONS V Ramping Up, MODE/SYNC = 0V FBX V Ramping Down, MODE/SYNC = 0V FBX Note 3: The LTC3407-4 is tested in a proprietary test mode that connects V to the output of the error amplifier. FB Note 4: Dynamic supply current is higher due to the internal gate charge being delivered at the switching frequency. Note calculated from the ambient T ...
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... LTC3407 TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Input Voltage 100 95 LOAD = 100mA LOAD = 10mA 90 85 LOAD = 800mA 80 LOAD = 1mA 1.8V 55 OUT Burst Mode OPERATION INPUT VOLTAGE (V) 34074 G04 Reference Voltage vs Temperature 0.615 V = 3.6V IN 0.610 0.605 0.600 ...
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... Output Feedback. Receives the feedback FB2 voltage from the external resistive divider across the output. Nominal voltage for this pin is 0.6V. or GND, Burst Mode Exposed Pad (GND) (Pin 11): Power Ground. Connect to the (–) terminal of C connected to electrical ground on PCB. LTC3407-4 Line Regulation 0 1.8V OUT I = 200mA ...
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... V 10 FB2 U OPERATIO The LTC3407-4 uses a constant frequency, current mode architecture. The operating frequency is set at 2.25MHz and can be synchronized to an external oscillator. Both channels share the same clock and run in-phase. To suit a variety of applications, the selectable Mode pin allows the user to choose between low noise and high efficiency. ...
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... An important design consideration is that the R the P-channel switch increases with decreasing input supply voltage (See Typical Performance Characteristics). Therefore, the user should calculate the power dissipation when the LTC3407-4 is used at 100% duty cycle with low input voltage (See Thermal Considerations in the Applica- is below TH tions Information Section) ...
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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 LTC3407-4 requires to operate. Table 1 shows some typical surface mount inductors that work well in LTC3407-4 applications. Input Capacitor (C ...
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... In 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 LTC3407-4 in parallel with the main capacitors for high frequency decoupling ...
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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 LTC3407-4 can also be synchronized to an external 2.25MHz clock signal (such as the SW pin on another LTC3407-4) by the MODE/SYNC pin. During synchroniza- ...
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... L The junction temperature RISE As an example, consider the case when the LTC3407 dropout on both channels at an input voltage of 2.7V with a load current of 800mA and an ambient temperature )(1 – DC) of 70°C. From the Typical Performance Characteristics graph of Switch Resistance, the R main switch is 0.425Ω. Therefore, power dissipated by ...
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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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... L1, L2: SUMIDA CDRH2D18/HP-4R7NC R5 100k RUN1 POWER-ON POR RESET L1 2.2µH V OUT1 1.8V SW1 C4, 22pF 800mA V FB1 604k 10µF 301k 3407 TA07 LTC3407-4 Efficiency vs Load Current 100 1.8V OUT 1.2V OUT 3.6V IN PULSE SKIP MODE 55 NO LOAD ON OTHER CHANNEL 50 10 ...
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... LTC3407-4 PACKAGE DESCRIPTIO 3.50 ±0.05 1.65 ±0.05 2.15 ±0.05 (2 SIDES) 0.25 ± 0.05 0.50 BSC 2.38 ±0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS NOTE: 1. DRAWING TO BE MADE A JEDEC PACKAGE OUTLINE M0-229 VARIATION OF (WEED-2). CHECK THE LTC WEBSITE DATA SHEET FOR CURRENT STATUS OF VARIATION ASSIGNMENT 2. DRAWING NOT TO SCALE 3 ...
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... DETAIL “A” 0° – 6° TYP 0.53 ± 0.152 (.021 ± .006) DETAIL “A” SEATING PLANE 0.17 – 0.27 (.007 – .011) TYP LTC3407-4 BOTTOM VIEW OF EXPOSED PAD OPTION 2.06 ± 0.102 (.081 ± .004) 1 1.83 ± 0.102 (.072 ± .004) 10 0.497 ± 0.076 (.0196 ± ...
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... Synchronous Buck-Boost DC/DC Converter 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 L2 LTC3407-4 D1 15µH SW2 C5, 22pF M1 V FB2 R4 GND C3 R3 887k 4.7µF 196k C1, C2: TAIYO YUDEN JMK316BJ106ML L1: MURATA LQH32CN2R2M33 C3: MURATA GRM21BR60J475KA11B ...