LTC1628CUH Linear Technology, LTC1628CUH Datasheet

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... The LTC1628-PG includes a power good output pin that replaces the FLTCPL, fault coupling control pin of the LTC1628. , LTC and LT are registered trademarks of Linear Technology Corporation. OPTI-LOOP and Burst Mode are registered trademarks of Linear Technology Corporation ...

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... TH1, 2 (Note 3.6V to 30V (Note 3) IN (Note 3) Measured in Servo Loop; I Voltage = 1.2V to 0.7V TH Measured in Servo Loop; I Voltage = 1. Voltages ...2.7V to – 0.3V OSENSE1 OSENSE2 ORDER PART TOP VIEW NUMBER LTC1628CUH LTC1628IUH 24 BOOST1 BG1 22 21 EXTV CC 20 INTV CC PGND 19 18 BG2 ...

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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER g Transconductance Amplifier g m1 Transconductance Amplifier GBW mGBW1 Input DC Supply Current Q Normal Mode Standby Shutdown V Forced Continuous Threshold FCB I Forced ...

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... Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note calculated from the ambient temperature T J dissipation P according to the following formulas: D LTC1628G/LTC1628G-PG • LTC1628CUH • Note 3: The LTC1628/LTC1628-PG are tested in a feedback loop that servos specified voltage and measures the resultant ITH1 OSENSE1 ...

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W U TYPICAL PERFOR A CE CHARACTERISTICS Supply Current vs Input Voltage and Mode (Figure 13) 1000 800 600 BOTH CONTROLLERS ON 400 200 STANDBY SHUTDOWN INPUT VOLTAGE (V) 1628 G04 ...

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LTC1628/LTC1628- TYPICAL PERFOR A CE CHARACTERISTICS Load Regulation 0.0 FCB = 15V IN FIGURE 1 –0.1 –0.2 –0.3 –0 LOAD CURRENT (A) 1628 G13 Maximum Current Sense Threshold vs Temperature ...

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W U TYPICAL PERFOR A CE CHARACTERISTICS Input Source/Capacitor Instantaneous Current (Figure 13 2A/DIV V IN 200mV/DIV V SW1 10V/DIV V SW2 10V/DIV V = 15V 1 s/DIV 1628 G22 OUT ...

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LTC1628/LTC1628- CTIO S RUN/SS1, RUN/SS2: Combination of soft-start, run con- trol inputs and short-circuit detection timers. A capacitor to ground at each of these pins sets the ramp time to full output current. Forcing either ...

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CTIO S PGOOD: (LTC1628-PG Only) Open-Drain Logic Output. PGOOD is pulled to ground when the voltage on either V pin is not within 7.5% of its set point. OSENSE CTIO AL DIAGRA ...

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LTC1628/LTC1628-PG U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC1628 uses a constant frequency, current mode step-down architecture with the two controller channels operating 180 degrees out of phase. During normal opera- tion, each top MOSFET is turned ...

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U OPERATIO (Refer to Functional Diagram) Frequency Setting The FREQSET pin provides frequency adjustment of the internal oscillator from approximately 140kHz to 310kHz. This input is nominally biased through an internal resistor to the 1.19V reference, setting the oscillator frequency ...

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LTC1628/LTC1628-PG U OPERATIO (Refer to Functional Diagram) overcurrent and/or short-circuit condition. Foldback cur- rent limiting is also activated when the output voltage falls below 70% of its nominal level whether or not the short- circuit latchoff circuit is enabled. Even ...

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U OPERATIO (Refer to Functional Diagram) 3.0 SINGLE PHASE DUAL CONTROLLER 2.5 2.0 1.5 2-PHASE DUAL CONTROLLER 1.0 0 5V/ 3.3V/ INPUT VOLTAGE (V) Figure 4. RMS Input Current Comparison ...

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LTC1628/LTC1628- APPLICATIO S I FOR ATIO 2.5 2.0 1.5 1.0 0.5 0 120 170 220 OPERATING FREQUENCY (kHz) Figure 5. FREQSET Pin Voltage vs Frequency is increased the gate charge losses will be higher, reducing efficiency (see Efficiency ...

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U U APPLICATIO S I FOR ATIO EXTV Pin Connection). Consequently, logic-level CC threshold MOSFETs must be used in most applications. The only exception is if low input voltage is expected (V < 5V); then, sub-logic level threshold MOSFETs IN ...

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LTC1628/LTC1628- APPLICATIO S I FOR ATIO Medium voltage (20V to 35V) ceramic, tantalum, OS-CON and switcher-rated electrolytic capacitors can be used as input capacitors, but each has drawbacks: ceramic voltage coefficients are very high and may have audible ...

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U U APPLICATIO S I FOR ATIO Manufacturers such as Nichicon, United Chemicon and Sanyo can be considered for high performance through- hole capacitors. The OS-CON semiconductor dielectric capacitor available from Sanyo has the lowest (ESR)(size) product of any aluminum ...

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LTC1628/LTC1628- APPLICATIO S I FOR ATIO derived from the output during normal operation (4.7V < V < 7V) and from the internal regulator when the output OUT is out of regulation (start-up, short-circuit). If more cur- rent is ...

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U U APPLICATIO S I FOR ATIO Output Voltage The LTC1628 output voltages are each set by an external feedback resistive divider carefully placed across the output capacitor. The resultant feedback signal is com- pared with the internal precision 0.800V ...

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LTC1628/LTC1628- APPLICATIO S I FOR ATIO Fault Conditions: Overcurrent Latchoff The RUN/SS pins also provide the ability to latch off the controller(s) when an overcurrent condition is detected. The RUN/SS capacitor used initially to turn ...

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U U APPLICATIO S I FOR ATIO Fault Conditions: Overvoltage Protection (Crowbar) The overvoltage crowbar is designed to blow a system input fuse when the output voltage of the regulator rises much higher than nominal levels. The crowbar causes huge ...

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LTC1628/LTC1628- APPLICATIO S I FOR ATIO FCB Pin Operation The FCB pin can be used to regulate a secondary winding logic level input. Continuous operation is forced when the FCB pin drops below 0.8V. During ...

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U U APPLICATIO S I FOR ATIO reduced to half or alternatively the amount of output capacitance can be reduced for a particular application. A complete explanation is included in Design Solutions 10. (See www.linear.com.) Efficiency Considerations The percent efficiency ...

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LTC1628/LTC1628- APPLICATIO S I FOR ATIO Checking Transient Response The regulator loop response can be checked by looking at the load current transient response. Switching regulators take several cycles to respond to a step in DC (resistive) load ...

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U U APPLICATIO S I FOR ATIO Automotive Considerations: Plugging into the Cigarette Lighter As battery-powered devices go mobile, there is a natural interest in plugging into the cigarette lighter in order to conserve or even recharge battery packs during ...

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LTC1628/LTC1628- APPLICATIO S I FOR ATIO Design Example As a design example for one channel, assume V 12V(nominal 22V(max OUT and f = 300kHz. The inductance value is chosen first based on a 30% ...

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U U APPLICATIO S I FOR ATIO PC Board Layout Checklist When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the LTC1628. These items are also illustrated graphically in the layout ...

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LTC1628/LTC1628- APPLICATIO S I FOR ATIO BOLD LINES INDICATE HIGH, SWITCHING CURRENT LINES. KEEP LINES TO A MINIMUM LENGTH. signal ground and a small V OSENSE should be as close as ...

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U U APPLICATIO S I FOR ATIO opposites channel’s voltage and current sensing feedback pins. All of these nodes have very large and fast moving signals and therefore should be kept on the “output side” of the LTC1628 and occupy ...

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LTC1628/LTC1628-PG U TYPICAL APPLICATIO 59k 1 RUN/SS1 0 SENSE1 180pF 1000pF 3 – SENSE1 105k OSENSE1 20k 5 1% INTV FREQSET CC 6 STBYMD 33pF 0. FCB LTC1628 8 I TH1 15k ...

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... MOLD FLASH. MOLD FLASH, IF PRESENT, SHALL NOT EXCEED 0.20mm ON ANY SIDE 5. EXPOSED PAD SHALL BE SOLDER PLATED 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 represen- tation that the interconnection of its circuits as described herein will not infringe on existing patent rights. U ...

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... Synchronous Controller with 5-Bit Mobile VID Control LTC1929 2-Phase Synchronous Controller LTC3728 550kHz, Dual, 2-Phase Synchronous Step-Down Controller Adaptive Power and PolyPhase are trademarks of Linear Technology Corporation. Pentium is a registered trademark of Intel Corporation. SENSE Linear Technology Corporation 32 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ...