LTC3414 LINER [Linear Technology], LTC3414 Datasheet
LTC3414
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LTC3414 Summary of contents
Page 1
... OPTI-LOOP transient response to be optimized over a wide range of loads and output capacitors. The LTC3414 can be configured for either Burst Mode operation or forced continuous operation. Forced continu- ous operation reduces noise and RF interference while Burst Mode operation provides high efficiency by reduc- ing gate charge losses at light loads ...
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... Note 2: The LTC3414E is guaranteed to meet performance specifications from Specifications over the – operating ambient temperature range are assured by design, characterization and correlation with statistical process controls. Note 3: The LTC3414 is tested in a feedback loop that adjusts V achieve a specified error amplifier output voltage ( ...
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... 300 ACTIVE 250 200 150 100 SLEEP 50 0 2.25 2.75 3.25 3.75 4.25 4.75 5.25 INPUT VOLTAGE (V) 3414 G08 LTC3414 Switch On-Resistance vs Temperature 3.3V IN 120 100 80 PFET NFET –40 –25 – 110 125 TEMPERATURE ( C) 3414 G03 Frequency vs Input Voltage 1040 R ...
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... LTC3414 W U TYPICAL PERFOR A CE CHARACTERISTICS Efficiency vs Load Current, Burst Mode Operation 100 3. 0.001 0.01 0 LOAD CURRENT (A) 3414 G10 Efficiency vs Input Voltage 2.5V OUT OUT OUT ...
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... Burst Mode operation with the burst clamp set to the pin voltage. RUN/SS (Pin 4): Run Control and Soft-Start Input. Forcing this pin below 0.5V shuts down the LTC3414. In shutdown all functions are disabled. Less than supply current is consumed. A capacitor to ground from this pin sets the ramp time to full output current ...
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... PGOOD 17 U OPERATIO Main Control Loop The LTC3414 is a monolithic, constant-frequency, cur- rent-mode step-down DC/DC converter. During normal operation, the internal top power switch (P-channel MOSFET) is turned on at the beginning of each clock cycle. Current in the inductor increases until the current com- parator trips and turns off the top power MOSFET. The ...
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... Low Supply Operation voltage falls TH The LTC3414 is designed to operate down to an input supply voltage of 2.25V. One important consideration at low input supply voltages is that the R P-channel and N-channel power switches increases. The user should calculate the power dissipation when the ...
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... LTC3414 U U APPLICATIO S I FOR ATIO The basic LTC3414 application circuit is shown in Figure 1. External component selection is determined by the maxi- mum load current and begins with the selection of the operating frequency and inductor value followed by C and C . OUT Operating Frequency Selection of the operating frequency is a tradeoff between efficiency and component size ...
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... V OUT The resistive divider allows pin V the output voltage as shown in Figure 2. LTC3414 large enough to damage the part sense a fraction OUT LTC3414 R1 SGND 3414 F02 Figure 2. Setting the Output Voltage 3414f 9 ...
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... BURST Soft-Start The RUN/SS pin provides a means to shut down the LTC3414 as well as a timer for soft-start. Pulling the RUN/SS pin below 0.5V places the LTC3414 in a low quiescent current shutdown state (I The LTC3414 contains an internal soft-start clamp that regardless of further gradually raises the clamp on I pulled above 2V ...
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... Thermal Considerations In most applications, the LTC3414 does not dissipate much heat due to its high efficiency However, in applications where the LTC3414 is running loss high ambient temperature with low supply voltage and high duty cycles, such as in dropout, the heat dissipated may exceed the maximum junction temperature of the part ...
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... LTC3414 U U APPLICATIO S I FOR ATIO Design Example As a design example, consider using the LTC3414 in an application with the following specifications 2.7V to 4.2V 2.5V OUT I = 100mA 1MHz. OUT(MIN) Because efficiency is important at both high and low load current, Burst Mode operation will be utilized. ...
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... APPLICATIO S I FOR ATIO Top R SS 2.2M 1000pF + C *** IN2 330 F * VISHAY DALE IHLP-2525CZ-01 ** SANYO POSCAP 4TPD470M *** SANYO POSCAP 6TPB330M Figure 4. 2.5V, 4A Regulator at 1MHz, Burst Mode Operation W U Figure 3. LTC3414 Layout Diagram 1 20 PGND PGND C ITH R 470pF OSC 294k X7R ITH 20k ...
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... OSC 294k X7R ITH 12. 1.25MHz SYNC/MODE I TH CLOCK PGOOD RUN/ 1000pF 5 X7R 16 SV SGND IN LTC3414 *** IN2 220 PGND PGND C C 100pF X7R R2 200k ITH ...
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... BSC (.0077 – .0118) 4. RECOMMENDED MINIMUM PCB METAL SIZE FOR EXPOSED PAD ATTACHMENT MILLIMETERS (INCHES) *DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.150mm (.006") PER SIDE LTC3414 6.40 – 6.60* (.252 – .260) 4.95 (.195 2.74 6.40 (.108) BSC ...
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... PGND PGND R OSC 294k SYNC/MODE 2. RUN/SS PGOOD C SS 1000pF, X7R 5 16 SGND SV IN LTC3414 IN2 9 12 470 PGND PGND COMMENTS 90% Efficiency 1.9mA 90% Efficiency ...