LTC1436AIGN Linear Technology, LTC1436AIGN Datasheet
LTC1436AIGN
Specifications of LTC1436AIGN
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LTC1436AIGN Summary of contents
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... The operating current level is user-programmable via an external current sense resistor. Wide input supply range allows operation from 3.5V to 30V (36V maximum). , LTC and LT are registered trademarks of Linear Technology Corporation. Adaptive Power is a trademark of Linear Technology Corporation. All other trademarks are the property of their respective owners. ...
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... AUXDR GN PACKAGE 24-LEAD PLASTIC SSOP (150 MIL SSOP) = 125°C, θ 110°C/W JMAX JA ORDER PART NUMBER LTC1436ACGN-PLL LTC1436AIGN-PLL The ● denotes the specifications which apply over the full operating = 25° 15V unless otherwise noted RUN/SS CONDITIONS V Pin Open (Note 3) ...
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ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are at T SYMBOL PARAMETER V Reference Voltage Line Regulation LINEREG V Output Voltage Load Regulation LOADREG V Secondary Feedback Threshold SFB I Secondary Feedback Current SFB V Output Overvoltage Lockout OVL I V ...
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... V AUXFB Divider Disconnect Voltage TH AUXDR 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 LTC1436ACGN/LTC1436ACGN-PLL/LTC1436AEGN/LTC1436AIGN/ )(110 °C/W) LTC1436AIGN-PLL )(95 °C/W) LTC1437ACG/LTC1437AIG Note 3: The LTC1436A/LTC1437A are tested in a feedback loop which ...
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... Input Voltage 2.5 2 OUT 1.5 EXTV = V CC OUT V = 3.3V 1.0 OUT EXTV = OPEN CC 0.5 SHUTDOWN INPUT VOLTAGE (V) 1436 G07 Burst Mode is a registered trademark of Linear Technology Corporation. Efficiency vs Input Voltage OUT 100 V OUT LOAD 100mA LOAD INPUT VOLTAGE (V) Load Regulation 0.033Ω ...
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LTC1436A LTC1436-PLL-A/LTC1437A W U TYPICAL PERFORMANCE CHARACTERISTICS Normalized Oscillator Frequency vs Temperature – 5 –10 – 40 – 110 135 TEMPERATURE (°C) 1436 G10 Maximum Current Sense Threshold Voltage vs Temperature 154 ...
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W U TYPICAL PERFORMANCE CHARACTERISTICS Auxiliary Regulator Sink Current Available AUX DR VOLTAGE (V) 1436 G19 PIN FUNCTIONS V : Main Supply Pin. ...
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LTC1436A LTC1436-PLL-A/LTC1437A PIN FUNCTIONS Forcing this pin below 1.3V causes the device to be shut down. In shutdown all functions are disabled. TGL: High Current Gate Drive for Main Top N-Channel MOSFET. This is the output of ...
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U U FUNCTIONAL DIAGRA W LTC1436A LTC1436A-PLL/LTC1437A 14367afb 9 ...
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LTC1436A LTC1436-PLL-A/LTC1437A U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC1436A/LTC1437A use a constant frequency, cur- rent mode step-down architecture. During normal opera- tion, the top MOSFET is turned on each cycle when the oscillator sets the RS ...
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U OPERATIO (Refer to Functional Diagram) Power-On Reset The POR pin is an open drain output which pulls low when the main regulator output voltage is out of regulation. When the output voltage rises to within 7.5% of regula- tion, ...
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LTC1436A LTC1436-PLL-A/LTC1437A U U APPLICATIONS INFORMATION ⎡ ⎢ OSC ⎢ Frequency kHz ⎣ A graph for selecting C vs frequency is given in Figure OSC 2. ...
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U U APPLICATIONS INFORMATION Inductor Core Selection Once the value for L is known, the type of inductor must be selected. High efficiency converters generally cannot afford the core loss found in low cost powdered iron cores, forcing the use ...
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LTC1436A LTC1436-PLL-A/LTC1437A U U APPLICATIONS INFORMATION where δ is the temperature dependency constant inversely related to the gate drive current. 2 Both MOSFETs have I R losses while the topside N-channel equation includes an additional term ...
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U U APPLICATIONS INFORMATION include Sanyo OS-CON, Nichicon PL series and Sprague 593D and 595D series. Consult the manufacturer for other specific recommendations. INTV Regulator CC An internal P-channel low dropout regulator produces the 5V supply that powers the drivers ...
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LTC1436A LTC1436-PLL-A/LTC1437A U U APPLICATIONS INFORMATION + BAT85 LTC1436A V IN LTC1437A N-CH TGL L1 EXTV N-CH TGS CC SW N-CH BG PGND Figure 4b. Capacitive Charge Pump for EXT V Topside MOSFET Driver Supply (C ...
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U U APPLICATIONS INFORMATION An internal 3µA current source charges up an external capacitor C When the voltage on RUN/SS reaches 1.3V SS. the LTC1436A/LTC1437A begin operating. As the voltage on RUN/SS continues to ramp from 1.3V to 2.4V, the ...
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LTC1436A LTC1436-PLL-A/LTC1437A U U APPLICATIONS INFORMATION The output of the phase detector is a complementary pair of current sources charging or discharging the external filter network on the PLL LPF pin. The relationship between the PLL LPF pin and operating ...
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U U APPLICATIONS INFORMATION The divided down voltage at the negative (–) input to the comparator is compared to an internal 1.19V reference. A 20mV hysteresis is built in to assure rapid switching. The output is an open drain MOSFET ...
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LTC1436A LTC1436-PLL-A/LTC1437A U U APPLICATIONS INFORMATION 1:N SECONDARY WINDING V SEC LTC1436A LTC1437A AUXDR R6 + AUXFB SFB R5 AUXON ON/OFF ( ) 1.19V 1 + > 13V SEC R5 Figure 11a. 12V Output Auxiliary Regulator Using ...
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U U APPLICATIONS INFORMATION INDUCTOR L 1435A F08 Figure 13. Allowable Inductor/R SENSE Efficiency Considerations The efficiency of a switching regulator is equal to the output power divided by the input power times 100 often useful to analyze ...
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LTC1436A LTC1436-PLL-A/LTC1437A U U APPLICATIONS INFORMATION A second, more severe transient is caused by switching in loads with large (>1µF) supply bypass capacitors. The discharged bypass capacitors are effectively put in parallel with C , causing a rapid drop in ...
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U U APPLICATIONS INFORMATION The power dissipation on the topside MOSFET can be easily estimated. Choosing a Siliconix Si4412DY results in 0.042Ω 100pF. At maximum input DS(ON) RSS voltage with T (estimated) = 50° ...
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LTC1436A LTC1436-PLL-A/LTC1437A U U APPLICATIONS INFORMATION 100pF 1000pF BOLD LINES INDICATE HIGH CURRENT PATHS U TYPICAL APPLICATIONS Intel Mobile CPU VID Core Power Converter with 1.8V I/O Supply 0.1µF 10k 1 ...
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U TYPICAL APPLICATIO S LTC1436A 3.3V/4A Fixed Output with 5V Auxiliary Output C OSC 68pF 1 C OSC 2 RUN/ 0.1µF 51pF LBO 4 LBI C C 510pF 10k ...
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LTC1436A LTC1436-PLL-A/LTC1437A U TYPICAL APPLICATIONS LTC1436A-PLL 3.3V/4A Fixed Output with 12V/500mA Auxiliary Output 0.01µF 10k 1 PLL LPF C 2 OSC C OSC 68pF RUN/SS 0.1µF R 10k ...
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... FLASH SHALL NOT EXCEED .254mm (.010") PER SIDE 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. ...
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... C OUT 100µF 10V × 2 MBRS140T3 SGND (PIN 8) 47k 100k 1436 TA06 ≤ 20V IN ≤ 20V IN ≤ 40V, For Logic Threshold FETs IN ® II Compliant LT/TP 0605 REV B 1K • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 1996 OUT 14367afb ...