LTC3544 LINER [Linear Technology], LTC3544 Datasheet
LTC3544
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LTC3544 Summary of contents
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... Schottky diodes. Low output voltages are easily supported with the 0.8V feedback reference voltage. The LTC3544 is available in a low profi le (0.75mm) (3mm × 3mm) QFN package. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. ...
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... LTC3544EUD#TRPBF LEAD BASED FINISH TAPE AND REEL LTC3544EUD LTC3544EUD#TR Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi ...
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... I = 100mA –100mA SW Note 2: The LTC3544E is guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls. LTC3544 MIN TYP ...
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... OUT LOAD 4 and power Note 5: The LTC3544 is tested in a proprietary test mode that connects the output of the error amplifi er. Note 6: Load regulation is inferred by measuring the regulation loop gain. Note 7: The QFN switch on-resistance is guaranteed by correlation to wafer level measurements. ...
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... V OUT200A 50mV/DIV AC COUPLED I L 250mA/DIV I LOAD 250mA/DIV V = 3.6V 20μs/DIV 0.8V OUT T = 25° 600μA TO 200mA LOAD LTC3544 Effi ciency vs Load Current 200mA Channel B. All Other Channels Off 100 2.25V 3. 4. 0.0001 0.001 ...
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... LTC3544 TYPICAL PERFORMANCE CHARACTERISTICS Load Step Response 100mA Channel V OUT100 50mV/DIV AC COUPLED I L 100mA/DIV I LOAD 100mA/DIV 1.2V OUT T = 25° 400μA TO 100mA LOAD PFET R DS(ON) 1.2 1.0 0.8 0.6 0.4 0 2.5 3 3.5 PFET R DS(ON) 1 3.6V IN 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0 –50 –30 –10 TEMPERATURE (° OUT100 1mV/DIV V OUT200A 1mV/DIV ...
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... Circuitry. Power path supply pin for the 100mA regulator. RUN200B (Pin 16): 200mA Regulator B Enable Pin. Forcing this pin to V enables the 200mA regulator (channel B), IN while forcing it to GND causes the regulator to shut off. Exposed Pad (Pin 17): Ground. Must be soldered to PCB. LTC3544 3544fa 7 ...
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... LTC3544 FUNCTIONAL DIAGRAMS 3 9 RUN200A SW200A 5 POWER FETs V FB200A 2 REG200A SW300 8 POWER FETs V FB300 10 REG300 REGULATOR V – 1 FBx EA + 0.8V SOFT-START SHUTDOWN 0.8V V OSC REF RUN300 V GNDA CC SHDN 0.8V OSC REF RUN LOGIC I BIAS200A I BIAS300 PV PGND BURST CLAMP SLOPE COMP – SLEEP I TH ...
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... R (see Typical Performance Characteristics). Therefore, the user should calculate the power dissipation when the LTC3544 is used at 100% duty cycle with low input voltage (see Thermal Considerations in the Applications Information section). LTC3544 OUT100 ...
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... LTC3544 APPLICATIONS INFORMATION The basic LTC3544 application circuit is shown on the fi rst page of this data sheet. External component selection is driven by the load requirement and begins with the selec- tion of L followed by C and OUT Inductor Selection For most applications, the value of the inductor will fall in the range of 1μ ...
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... ESR make them ideal for switching regulator applications. Because the LTC3544’s control loop does not depend on the output capacitor’s ESR for stable operation, ceramic capacitors can be used freely to achieve very low output ripple and small circuit size ...
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... T is the ambient temperature and the duty cycle As an example, consider the LTC3544 in dropout at an input voltage of 2.5V, a total load current (all four regula- tors) of 800mA and an ambient temperature of 85°C. From )(1 – DC) the Typical Performance graphs of switch resistance, the R of the 300mA P-channel switch at 85° ...
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... unshielded inductors in order to minimize any trans- former coupling. Design Example As a design example, consider using the LTC3544 as a portable application with a Li-Ion battery. The battery provides V 2.5V is 250mA necessitating the use of the 300mA output for this requirement. GNDA ...
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... C9 4.7μ RUN200B RUN100 4.7μH 4 SW200B SW100 C6 20pF FB200B FB100 LTC3544 L3 3 RUN200A RUN300 4.7μH 5 SW200A SW300 FB200A FB300 GNDA PGND 14 6 Figure 5. Design Example ...
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... Plastic QFN (3mm × 3mm) (Reference LTC DWG # 05-08-1691) 0.70 ±0.05 PACKAGE OUTLINE 0.25 ±0.05 0.50 BSC BOTTOM VIEW—EXPOSED PAD R = 0.115 0.75 ± 0.05 TYP 1.45 ± 0.10 (4-SIDES) 0.200 REF 0.00 – 0.05 LTC3544 PIN 1 NOTCH R = 0.20 TYP OR 0.25 × 45° CHAMFER 15 16 0.40 ± 0. (UD16) QFN 0904 0.25 ± 0.05 0.50 BSC 3544fa 15 ...
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... Requlators LTC3531/LTC3531-3 200mA I , 1.5MHz, Synchronous Buck-Boost DC/DC OUT LTC3531-3.3 Converters LTC3532 500mA I , 2MHz, Synchronous Buck-Boost DC/DC OUT Converter LTC3544B 300mA, 2 × 200mA, 100mA Quad 2.25MHz Synchronous Buck DC/DC Converter LTC3547/LTC3547B Dual 300mA I , 2.25MHz, Synchronous Step-Down OUT DC/DC Converter LTC3548/LTC3548-1 Dual 400mA/800mA I OUT LTC3548-2 Step-Down DC/DC Converters LTC3561 1 ...