LTC3404 LINER [Linear Technology], LTC3404 Datasheet
LTC3404
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LTC3404 Summary of contents
Page 1
... Supply current during operation is only 10 A and drops to < shutdown. The 2.65V to 6V input voltage range makes the LTC3404 ideally suited for single Li-Ion battery-powered applications. 100% duty cycle provides low dropout operation, extending battery life in portable systems ...
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... RUN 0. < f PLLIN OSC f > f PLLIN OSC I = 100mA –100mA ORDER PART NUMBER 8 PLL LPF 7 SYNC/MODE LTC3404EMS8 MS8 PART MARKING = 150 LTKR MIN TYP MAX 4 30 0.784 0.8 0.816 0.74 0.8 0. 110 0.05 0.2 0.1 0.5 – 0.1 – 0.5 2.65 6 ...
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... RUN Rising SYNC/MODE V Rising RUN Note 4: The LTC3404 is tested in a feedback loop which servos V balance point for the error amplifier (V Note 5: Dynamic supply current is higher due to the gate charge being delivered at the switching frequency. and power A Efficiency vs Output Current 100 ...
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... LTC3404 W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Output Current 3. 4. 1.8V OUT 100 1000 OUTPUT CURRENT (mA) 3404 G04 Oscillator Frequency vs Temperature 1. 3.6V IN 1.50 1.45 1.40 1.35 1.30 1.25 –50 – 100 125 0 TEMPERATURE ( C) 3404 G06 R vs Input Voltage DS(ON) 0 ...
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... I L 500mA/DIV I TH 1V/DIV 40 s/DIV OUT OUT 50mA TO 500mA LOAD 3404 G18 PULSE SKIPPING MODE LTC3404 Switch Leakage vs Input Voltage 1.2 RUN = 0V 1.0 SYNCHRONOUS SWITCH 0.8 0.6 0.4 MAIN SWITCH 0.2 0 125 INPUT VOLTAGE (V) Start-Up from Shutdown RUN ...
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... PI FU CTIO S RUN (Pin 1): Run Control Input. Forcing this pin below 0.4V shuts down the LTC3404. In shutdown all functions are disabled drawing < supply current. Forcing this pin above 1.2V enables the LTC3404. Do not leave RUN floating. I (Pin 2): Error Amplifier Compensation Point. The ...
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... When locked, the PLL aligns the turn-on of the top MOSFET to the rising edge of the synchronizing signal. When the LTC3404 is clocked by an external source, Burst Mode operation is disabled; the LTC3404 then operates in PWM pulse skipping mode. In this mode, when the output ...
Page 8
... Another important detail to remember is that at low input supply voltages, the R increases. Therefore, the user should calculate the power dissipation when the LTC3404 is used at 100% duty cycle with a low input voltage (see Thermal Considerations in the Applications Information section). Slope Compensation and Inductor Peak Current ...
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... OUT where f = operating frequency, C and I = ripple current in the inductor. The output ripple L is highest at maximum input voltage since I with input voltage. For the LTC3404, the general rule for proper operation is: C required ESR < 0.25 OUT The choice of using a smaller output capacitance increases the output ripple voltage due to the frequency ...
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... GND Figure 3. Setting the LTC3404 Output Voltage Phase-Locked Loop and Frequency Synchronization The LTC3404 has an internal voltage-controlled oscillator and phase detector comprising a phase-locked loop. This allows the top MOSFET turn- locked to the rising edge of an external frequency source. The frequency range of the voltage-controlled oscillator is 1MHz to 1 ...
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... L1, L2, etc. are the individual losses as a percentage of input power. Although all dissipative elements in the circuit produce losses, two main sources usually account for most of the losses in LTC3404 circuits: V quiescent current and I IN losses. The V quiescent current loss dominates the ...
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... where T is the ambient temperature example, consider the LTC3404 in dropout at an input voltage of 3V, a load current of 500mA, and an ambient temperature From the typical perfor- mance graph of switch resistance, the R OPTIONAL P-channel switch approximately 0.7 . There- ...
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... Keep the switching node SW away from sensitive small signal nodes Design Example As a design example, assume the LTC3404 is used in a single lithium-ion battery-powered cellular phone applica regulator can OUT tion. The input voltage will be operating from a maximum of 4.2V down to about 2.7V. The load current requirement is a maximum of 0 ...
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... Figure 8. Single Lithium-Ion to 2.5V/0.3A Regulator from Design Example U TYPICAL APPLICATIO S LTC3404 1 RUN 47pF GND * TOKO D52LC A914BYW-4R7M ** TAIYO-YUDEN CERAMIC JMK325BJ226MM *** TAIYO-YUDEN CERAMIC LMK325BJ106MN LTC3404 1 RUN 47pF GND * TOKO D52LC A914BYW-4R7M ** TAIYO-YUDEN CERAMIC JMK325BJ226MM *** TAIYO-YUDEN CERAMIC LMK325BJ106MN ...
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... TA06 3- to 4-Cell NiCd/NiMH to 3.3V/0.5A Regulator Using All Ceramic Capacitors 8 PLL LPF 4 20pF 887k 280k 3404 TA06 FOR 2.7V < V < 3. LTC3404 *** OUT IN 2. OUT 0.6A CER 22 F CER V IN 2.65V *** ...
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... Low Input Voltage Current Mode Step-Down DC/DC Controller LTC1877 High Efficiency Monolithic Step-Down Regulator LTC1878 High Efficiency Monolithic Step-Down Regulator Linear Technology Corporation 16 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear-tech.com 10k LTC3404 1 8 RUN PLL LPF SYNC/MODE TH ...