LTC3407A LINER [Linear Technology], LTC3407A Datasheet
LTC3407A
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LTC3407A Summary of contents
Page 1
... V RUN/SS1 IN POR RESET 2.2μ 1.8V OUT1 SW1 AT 600mA 22pF V FB1 887k GND 442k 10μF 3407A TA01 LTC3407A 1.5MHz Step-Down DC/DC Regulator LTC3407A Effi ciency/Power Loss Curve 100 1 2.5V 90 1. 0.001 3.3V IN Burst Mode OPERATION 10 NO LOAD ON OTHER CHANNEL 0.0001 0 ...
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... Feedback Voltage (Note 3) FB ΔV Reference Voltage Line Regulation LINE REG 2 (Note 1) Operating Temperature Range (Note 2) LTC3407AE .......................................... –40°C to 85°C LTC3407AI ......................................... –40°C to 125°C IN Junction Temperature (Note 5) ............................. 125° 0.3V Storage Temperature Range ...................– 65°C to 150°C IN Lead Temperature (Soldering, 10 sec) LTC3407AMSE Only .......................................... 300° ...
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... V Ramping Up, MODE/SYNC = 0V FBX V Ramping Down, MODE/SYNC = 0V FBX Note 3: The LTC3407A is tested in a proprietary test mode that connects V to the output of the error amplifi er. FB 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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... LTC3407A TYPICAL PERFORMANCE CHARACTERISTICS Load Step V OUT1 200mV/DIV V OUT2 100mV/DIV I L 500mA/DIV I LOAD 500mA/DIV 20μs/DIV 1.8V OUT I = 50mA TO 600mA LOAD CIRCUIT OF FIGURE 3 Effi ciency vs Input Voltage 100 100mA 90 600mA 80 10mA 1mA 1.8V 10 OUT CIRCUIT OF FIGURE ...
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... When tied to V operation or pulse skipping mode is selected, respectively. Do not fl oat this pin. The oscillation frequency can be synchronized to an external oscillator applied to this pin and pulse skipping mode is automatically selected. LTC3407A T = 25°C unless otherwise specifi ed. A Load Regulation ...
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... LTC3407A PIN FUNCTIONS SW2 (Pin 7): Regulator 2 Switch Node Connection to the Inductor. This pin swings from V IN POR (Pin 8): Power-On Reset. This common-drain logic output is pulled to GND when the output voltage is not within ±8.5% of regulation and goes high after 2 cycles when both channels are within regulation. ...
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... P-channel switch increases with decreasing input pin to the supply voltage (See Typical Performance Characteristics). FB Therefore, the user should calculate the power dissipation when the LTC3407A is used at 100% duty cycle with low TH input voltage (See Thermal Considerations in the Applica- tions Information Section). Low Supply Operation ...
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... ments and any radiated fi eld/EMI requirements than on OUT1 what the LTC3407A requires to operate. Table 1 shows 3407A F01 some typical surface mount inductors that work well in LTC3407A applications. Table 1. Representative Surface Mount Inductors MANUF- ...
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... Other capacitor types include the Panasonic Special Polymer (SP) capacitors. In most cases, 0.1μF to 1μF of ceramic capacitors should also be placed close to the LTC3407A in parallel with the ) is OUT main capacitors for high frequency decoupling. ...
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... The LTC3407A can also be synchronized to another LTC3407A by the MODE/SYNC pin. During synchroniza- tion, the mode is set to pulse skipping and the top switch turn-on is synchronized to the rising edge of the external clock ...
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... In addition, they can optionally be used to externally control the rate at which each regulator starts up and shuts down. Pulling the RUN/SS1 pin below 1V shuts down regulator 1 on the LTC3407A. Forcing this pin to V enables regulator 1. In order to control the rate ...
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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 LTC3407A in a portable application with a Li-Ion battery. The battery pro- vides 2.8V to 4.2V. The load requires a maximum IN of 600mA in active mode and 2mA in standby mode. The ...
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... AC current to the internal power MOSFETs and their drivers. V OUT2 C OUT2 BOLD LINES INDICATE HIGH CURRENT PATHS Figure 2. LTC3407A Layout Diagram (See Board Layout Checklist) 2. Are C OUT C returns current to GND and the (–) plate of C OUT 3. The resistor divider formed by R1 and R2 must be connected between the (+) plate of C sense line terminated near GND (exposed pad) ...
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... L1 2.2μ 1.8V OUT1 SW1 AT 600mA C4, 22pF V FB1 604k 10μF 301k 3407A TA03 R7 100k V IN 4.7MΩ POWER-ON POR LTC3407A RESET RUN/SS1 L1 4.7μ 1.2V OUT1 SW1 AT 600mA C1, 22pF 680pF V FB1 R2 GND C R1 604k OUT1 10μF 604k L1, L2: TDK VLF3010AT-4R7MR70 Effi ciency vs Load Current 100 2 ...
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... DETAIL “A” 0.254 (.010) 0 – 6 TYP 0.53 0.152 1.10 (.021 .006) (.043) MAX DETAIL “A” SEATING PLANE 0.17 – 0.27 (.007 – .011) 0.50 TYP (.0197) BSC LTC3407A R = 0.115 0.38 ± 0.10 TYP 6 10 3.00 ±0.10 1.65 ± 0.10 (2 SIDES) (4 SIDES) (DD) DFN 1103 5 1 0.25 ± 0.05 0.75 ±0.05 0.50 BSC 2.38 ±0.10 (2 SIDES) 0.00 – ...
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... Dual Synchronous Step-Down DC/DC Converter 16 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 2. 4.2V C1 10μF RUN/SS2 V RUN/SS1 IN POR MODE/SYNC LTC3407A L2 D1 10μH SW2 SW1 FB1 FB2 R4 GND C3 R3 887k 10μF 196k L1: MURATA LQH32CN2R2M33 L2: TOKO A914BYW-100M (D52LC SERIES) M1: SILICONIX Si2302 4 ...