LTC3619B Linear Technology, LTC3619B Datasheet
LTC3619B
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LTC3619B Summary of contents
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... The operating frequency is internally set at 2.25MHz allowing the use of small surface mount inductors. Internal soft-start reduces in-rush current during start-up. The LTC3619B is available in small MSOP and 3mm × 3mm DFN packages. The LTC3619B is also available in a low quiescent current, high efficiency Burst Mode LTC3619. RUN1 3.3µ ...
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... LTC3619BEDD#PBF LTC3619BEDD#TRPBF LTC3619BIDD#PBF LTC3619BIDD#TRPBF LTC3619BEMSE#PBF LTC3619BEMSE#TRPBF LTC3619BIMSE#PBF LTC3619BIMSE#TRPBF Consult LTC Marketing for parts specified with wider operating temperature ranges. *The temperature grade is identified by a label on the shipping container. Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: ...
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... Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: Guaranteed by long term current density limitations. Note 3: The LTC3619B is tested under pulsed load conditions such that T ≈ The LTC3619BE is guaranteed to meet performance specifications ...
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... LTC3619B Typical perForMance characTerisTics Pulse-Skipping Mode Operation SW 2V/DIV V OUT 50mV/DIV AC- COUPLED I L 100mA/DIV 5µs/DIV 3619B G01 3.3V OUT I = 5mA LOAD Regulated Voltage vs Temperature 1.5 1.0 0.5 0 –0.5 –1.0 –1.5 –50 – 100 TEMPERATURE (°C) 3619B G04 Switch On-Resistance vs Input Voltage ...
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... LOAD CURRENT (mA) Start-Up from Shutdown RUN 2V/DIV V OUT 1V/DIV I L 250mA/DIV 200µs/DIV 3.3V IN OUT R = 7Ω LOAD 5 4.7µF LOAD www.DataSheet4U.com LTC3619B T = 25° 5V, unless otherwise noted Efficiency vs Load Current 100 V = 1.2V OUT 90 CHANNEL 3. ...
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... LTC3619B Typical perForMance characTerisTics Average Input Current Limit vs Temperature 475mA 6 LIM –2 –4 –6 –8 –50 – 100 TEMPERATURE (°C) 3619B G19 pin FuncTions (DD/MSE) V (Pin 1/Pin 1): Regulator 1 Output Feedback. Receives FB1 the feedback voltage from the external resistive divider across the regulator 1 output ...
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... OSC MIN CLAMP SLOPE COMP – SLEEP – I COMP + V SLEEP LATCH R Q SWITCHING LOGIC AND BLANKING ANTI CIRCUIT SHOOT- THRU I RCMP SHUTDOWN www.DataSheet4U.com LTC3619B + + I COMP – + – + – COMP – + – SW1 GND 11 3 RLIM SW2 ...
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... P-channel switch increases with decreasing input supply voltage (see the Typical Performance Characteristics sec- tion). Therefore, the user should calculate the worst-case power dissipation when the LTC3619B is used at 100% duty cycle with low input voltage (see Thermal Considerations in the Applications Information section). ...
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... RLIM pin becomes 1A/55k = 18.2µA during the 50% on-time or 9.1µA full duty cycle. With a C capacitor of 1µ LIM it will take 110ms for C the time after which the LTC3619B will start input current www.DataSheet4U.com LTC3619B resistor will program the LIM current. As the input current PEAK voltage will follow ...
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... I LIM 0.66 = 13.2µA, where 0.66 is the duty cycle. It will take a little more than 7.5ms to charge the 1V, after which the LTC3619B begins to limit input current. The I current is not limited during this 7.5ms IN time and is more than 725mA. This current transient may ...
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... L or than on what the LTC3619B requires to operate. Table 1 IN shows some typical surface mount inductors that work well in LTC3619B applications. (1) Table 1. Representative Surface Mount Inductors ...
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... Their high ripple current, high voltage rating and low ESR make them ideal for switching regulator applications. Because the LTC3619B control loop does not depend on the output capacitor’s ESR for stable operation, ceramic capacitors equals ...
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... Efficiency = 100% – ( ...) where L1, L2, etc., are the individual losses as a percent- age of input power. Although all dissipative elements in the circuit produce losses, four sources usually account for the losses in LTC3619B circuits losses losses, 4) other system losses. 1. The V ...
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... Thermal Considerations In a majority of applications, the LTC3619B does not dis- sipate much heat due to its high efficiency. In the unlikely event that the junction temperature somehow reaches ap- proximately 150° ...
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... V IN 2.5V TO 5.5V V OUT2 C OUT2 BOLD LINES INDICATE HIGH CURRENT PATHS Figure 3a. LTC3619B Layout Diagram (See Board Layout Checklist) V OUT2 VIA TO V OUT2 RUN2 V RUN1 C1 IN PGOOD2 PGOOD1 L2 L1 SW2 SW1 C F2 LTC3619B V V FB1 FB2 R4 RLIM GND LIM ...
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... LTC3619B applicaTions inForMaTion Design Example As a design example, consider using the LTC3619B in a USB-GSM application, with the output of channel 2 charging a SuperCap of 4.4mF . The load on each channel requires a maximum of 400mA and 800mA in active mode and 2mA in standby mode. The output voltages are ...
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... V = 1.8V OUT 0.001 0 0.0001 0.1 1 Figure 4b. Efficiency vs Output Current V OUT 200mV/DIV V IN 1V/DIV AC-COUPLED I OUT 500mA/DIV I IN 500mA/DIV Figure 4c. Transient Response www.DataSheet4U.com LTC3619B 3.4V OUT 1 0 0.001 0.001 0.01 0.1 1 OUTPUT CURRENT (A) 3619B F04b 1ms/DIV V = 5V, 500mA COMPLIANT 116kΩ, C ...
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... LTC3619B package DescripTion 3.55 0.05 1.65 0.05 2.15 0.05 (2 SIDES) 0.25 0.05 2.38 0.05 (2 SIDES) RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS 2.794 0.102 (.110 .004) 5.23 (.206) MIN 0.305 0.038 (.0120 .0015) TYP RECOMMENDED SOLDER PAD LAYOUT 0.254 (.010) GAUGE PLANE 0.18 (.007) NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. ...
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... Updated DD Package Drawing Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. www.DataSheet4U.com LTC3619B PAGE NUMBER ...
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... LIM LIM 110k 1000pF : AVX 08056D106KAT2A L1: COILCRAFT LPS4012-332ML : VISHAY 592D228X96R3X2T20H L2: COILCRAFT LPS4012-152ML = 475mA or Disabled LIM 10µF RUN2 V RUN1 IN PGOOD2 PGOOD1 L2 L1 1.5µH 3.3µH LTC3619B SW2 SW1 1150k V V FB1 FB2 C OUT2 GND LIM 2.2mF 255k 255k 2 SuperCap R ...