ltc3548-1 Linear Technology Corporation, ltc3548-1 Datasheet
ltc3548-1
Related parts for ltc3548-1
ltc3548-1 Summary of contents
Page 1
... MOSFETs are turned on continuously in dropout (100% duty cycle), and both channels draw a total quiescent current of only 40μA. In shutdown, the device draws <1μA. The LTC3548-1 is available in both thin (0.75mm) and ultra-thin (0.55mm) 3mm × 3mm DFN packages. , LT, LTC, LTM and Burst Mode are registered trademarks of Linear Technology Corporation ...
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... LTC3548 ABSOLUTE AXI U RATI GS (Note 1) V Voltages.................................................– 0. FB1 FB2 OUT1 OUT2 RUN1, RUN2 Voltages .................... – 0. SW1, SW2 Voltage ......................... – 0. FIGURATIO TOP VIEW V 1 FB1 V 2 OUT1 SW1 4 GND 5 DD PACKAGE 10-LEAD (3mm × ...
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... IN RUN OUT1 OUT2 Note 3: The LTC3548-1 is tested in a proprietary test mode that connects the output of the error amplifier to an outside servo-loop. 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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... LTC3548 TYPICAL PERFOR A CE CHARACTERISTICS Burst Mode Operation SW 5V/DIV I L 200mA/DIV V OUT1 20mV/DIV 3548-1 G01 V = 3.6V 2μs/DIV 1.8V OUT1 I = 60mA LOAD CHANNEL 1; CIRCUIT OF FIGURE 3 Efficiency vs Input Voltage 100 100mA OUT 800mA OUT I = 10mA OUT 1mA ...
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... OUT1 0 1.575V OUT2 –0.5 –1.0 –1.5 –2 100 LOAD CURRENT (mA) 100 4. 100 1000 3548-1 G16 LTC3548 25°C unless otherwise specified. A Line Regulation 0.5 0.4 0 1.8V OUT1 0.2 0.1 V OUT2 0 –0.1 –0.2 –0.3 –0.4 –0.5 1000 2 4.5 3.5 LOAD CURRENT (mA) ...
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... LTC3548 CTIO S V (Pin 1): Output Feedback for Channel 1. Receives the FB1 feedback voltage from internal resistive divider across the output. Normal voltage for this pin is 0.6V. V (Pin 2): Output Voltage Feedback Pin for Channel 1. OUT1 An internal resistive divider divides the output voltage down for comparison to the internal reference voltage ...
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... R1 = 195k 120k FOR REGULATOR FB2 SLOPE COMP EN – SLEEP I TH BURST + 0.35V LATCH R Q SWITCHING UV LOGIC AND BLANKING CIRCUIT OV OSC LTC3548-1 BURST V CLAMP IN – + 5Ω I COMP ANTI SHOOT- THRU + I RCMP – 3548 SW1 11 GND GND ...
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... P-channel switch increases with decreasing input supply voltage (see Typical Performance Characteristics). Therefore, the user should calculate the power dissipation when the LTC3548-1 is used at 100% duty cycle with low input voltage (see Thermal Considerations in the Applica- tions Information section). Low Supply Operation ...
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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- is 0.8A for ments than on what the LTC3548-1 requires to operate. Table 1 shows some typical surface mount inductors that work well in LTC3548-1 applications. Table 1. Representative Surface Mount Inductors ...
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... LTC3548 APPLICATIO S I FOR ATIO Input Capacitor (C ) Selection IN In continuous mode, the input current of the converter is a square wave with a duty cycle of approximately prevent large voltage transients, a low equivalent IN series resistance (ESR) input capacitor sized for the maxi- mum RMS current must be used. The maximum RMS ...
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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 LTC3548-1 in parallel with the main capacitors for high frequency decoupling ...
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... LTC3548 APPLICATIO S I FOR ATIO Since the ESR of a ceramic capacitor is so low, the input and output capacitor must instead fulfill a charge storage requirement. During a load step, the output capacitor must instantaneously supply the current to support the load until the feedback loop raises the switch current enough to support the load ...
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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, 4 main sources usually account for most of the losses in LTC3548-1 circuits: 1)V 2) switching losses The V IN Electrical Characteristics which excludes MOSFET driver and control currents. V ...
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... The junction temperature RISE As an example, consider the case when the LTC3548 input voltage of 2.7V with a load current of 400mA and 800mA and an ambient temperature of 70°C. From the Typical Performance Characteristics graph of Switch Re- sistance, the R 0.425Ω. Therefore, power dissipated by each channel is: ...
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... U U APPLICATIO S I FOR ATIO Design Example As a design example, consider using the LTC3548 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. The output voltage 1.8V. OUT ...
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... LTC3548 APPLICATIO S I FOR ATIO GND VIA TO V OUT1 GND Figure 4. LTC3548-1 Layout Diagram Efficiency vs Load Current 100 1.8V OUT1 1.575V OUT2 100 LOAD CURRENT (mA) 3548-1 G11 V OUT2 C OUT2 GND ...
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... SW2 SW1 V V OUT2 OUT1 C FF2 330pF V V FB2 FB1 GND Efficiency vs Load Current 100 1.8V OUT1 1.575V OUT2 100 LOAD CURRENT (mA) 3548-1 G11 LTC3548-1 L1 2.2μH V OUT1 1.8V 800mA C2 C FF1 10μF 330pF CER 3548-1 TA07 1000 35481fa 17 ...
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... LTC3548-1 PACKAGE DESCRIPTIO 3.50 ±0.05 1.65 ±0.05 2.15 ±0.05 (2 SIDES) 0.25 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS PIN 1 TOP MARK (SEE NOTE 6) 0.200 REF 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 ...
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... Plastic UTDFN (3mm × 3mm) (Reference LTC DWG #05-08-1739 Rev Ø) 2.00 REF 0.675 ±0.05 2.38 ±0.05 1.65 ±0.05 PACKAGE OUTLINE 0.50 BSC 3.00 ±0. 0.05 TYP 3.00 ±0.10 0.55 ±0. 0.115 TYP 0.00 – 0.05 BOTTOM VIEW—EXPOSED PAD LTC3548-1 0.40 ± 0.10 2.00 REF 6 10 2.38 ±0.10 1.65 ± 0.10 (KD10) UTDFN 1106 REV Ø 0.25 ± 0.05 0.50 BSC 35481fa 19 ...
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... LTC3548-1 RELATED PARTS PART NUMBER DESCRIPTION LTC1878 600mA (I ), 550kHz, OUT Synchronous Step-Down DC/DC Converter LT1940 Dual Output 1.4A(I OUT) High Efficiency Step-Down DC/DC Converter LTC3252 Dual 250mA (I ), 1MHz, Spread Spectrum OUT Inductorless Step-Down DC/DC Converter LTC3405/LTC3405A 300mA (I ), 1.5MHz, OUT Synchronous Step-Down DC/DC Converters LTC3406/LTC3406B 600mA (I ), 1.5MHz, ...