ltc1149-5 Linear Technology Corporation, ltc1149-5 Datasheet
ltc1149-5
Related parts for ltc1149-5
ltc1149-5 Summary of contents
Page 1
... SENSE 1N5819 62 H 0.05 + 1000pF – + N-CHANNEL IRFR024 *COILTRONICS CTX62-2-MP **KRL SL-1-C1-0R050J LTC1149 LTC1149-3.3/LTC1149-5 U 1149 series is a family of synchronous step- TM operation to maintain high efficiencies at = 12V. In shutdown, IN LTC1149-5 Efficiency 100 FIGURE 1 CIRCUIT V = 12V 24V OUT IN 5V/ OUT 220 F 60 0.02 ...
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... Feedback Current (LTC1149 Only Regulated Output Voltage OUT LTC1149-3.3 LTC1149-5 V Output Voltage Line Regulation OUT Output Voltage Load Regulation LTC1149-3.3 LTC1149-5 Burst Mode Output Ripple I Input DC Supply Current (Note 3) 2 Normal Mode Burst Mode Shutdown V Internal Regulator Voltage CC (Sets MOSFET Gate Drive Levels) V – ...
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... T Note dissipation P according to the following formulas: D LTC1149CN, LTC1149CN-3.3, LTC1149CN-5: T LTC1149CS, LTC1149CS-3.3, LTC1149CS-5: T Note 2: Pin shutdown pin on the LTC1149-3.3 and LTC1149-5 fixed output voltage versions and must be at ground potential for testing 12V ...
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... INPUT VOLTAGE (V) Supply Current in Shutdown 400 SD2 300 200 100 INPUT VOLTAGE (V) Off-Time vs V OUT LTC1149-5 10 LTC1149-3 OUTPUT VOLTAGE (V) Load Regulation 20 FIGURE 1 CIRCUIT V = 24V IN 0 –20 –40 –60 –80 –100 50 0 0.5 1.0 1.5 ...
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... Pin 7 voltage. – SENSE (Pin 8): Connects to internal resistive divider which sets the output voltage in LTC1149-3.3 and LTC1149-5 versions. Pin 8 is also the (–) input for the current comparator. + SENSE (Pin 9): The (+) Input for the Current Comparator. ...
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... To minimize the frequency variation as dropout is approached, the off- . When the timing time controller increases the discharge current as V drops below V MOSFET is turned on continuously. W Pin 10 connection shown for LTC1149-3.3 and LTC1149-5; changes create LTC1149. 500k – S ...
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... R The load current below which Burst Mode operation commences both track I SC(PK and I SENSE BURST equations: equal to the peak MAX I BURST must be less than or I SC(PK) LTC1149 LTC1149-3.3/LTC1149-5 + 220 F IRF9Z34 100V MBR380 + IRFZ34 25k + 220 F + 75k 0.05 V – V ...
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... LTC1149 LTC1149-3.3/LTC1149 APPLICATIO S I FOR ATIO The LTC1149 series automatically extends t short circuit to allow sufficient time for the inductor current to decay between switch cycles. The resulting ripple current causes the average short-circuit current reduced to approximately I SC(AVG) 0.20 0.18 0.16 0.14 0.12 0.10 0.08 0.06 0.04 0. MAXIMUM OUTPUT CURRENT (A) Figure 2 ...
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... MOSFET as to the P-channel with regard to when logic- level devices are required. However, the dissipation calcu- lation is quite different. The duty cycle and dissipation for Kool registered trademark of Magnetics, Inc. LTC1149 LTC1149-3.3/LTC1149-5 , reverse transfer capacitance C DS(ON) V OUT V ...
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... LTC1149 LTC1149-3.3/LTC1149 APPLICATIO S I FOR ATIO the N-channel MOSFET operating in continuous mode are given by: V – OUT N-Ch Duty Cycle = – OUT 2 N- MAX V IN where is the temperature dependency of R that there is no transition loss term in the N-channel ...
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... IRFZ34 NGATE V FB 100pF + SENSE 1000pF – SENSE = 1. OUT R1 VALUES SHOWN FOR V = 12V OUT LTC1149 LTC1149-3.3/LTC1149 regulator can OUT to V Pin 10. The regulated OUT greater than the LTC1149 OUT voltage, R must be moved to CC SENSE 100 H R2 215k + 150 F ...
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... LTC1149 LTC1149-3.3/LTC1149 APPLICATIO S I FOR ATIO the ground side of the output to prevent the absolute maximum voltage ratings of the sense pins from being exceeded. This is shown in Figure 5. When the current sense comparator is operating at 0V common mode, the off-time increases approximately 40%, requiring the use of a smaller timing capacitor C ...
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... Burst Mode operation can be suppressed at low output currents with a simple external network which cancels the LTC1149 LTC1149-3.3/LTC1149-5 = 0.3 ) and a larger one, DS(ON) = 0.065 ). The results are DS(ON) P-CHANNEL MOSFET ...
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... LTC1149 LTC1149-3.3/LTC1149 APPLICATIO S I FOR ATIO 25mV minimum current comparator threshold. This tech- nique is also useful for eliminating audible noise from certain types of inductors in high current (I applications when they are lightly loaded. An external offset is put in series with the SENSE subtract from the built-in 25mV offset ...
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... When load currents are low (I operation should occur with the C cally falling to ground as shown in Figure 9b. If Pin 6 is observed falling to ground at high output currents, it indicates poor decoupling or improper ground- ing. Refer to the Board Layout Checklist. from possible capaci- LTC1149 LTC1149-3.3/LTC1149 N-CHANNEL – ...
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... LTC1149 LTC1149-3.3/LTC1149-5 TYPICAL APPLICATIO S 1N4148 0.068 F 0.047 390pF 3300pF 1k Figure 10. High Efficiency 8V to 20V Input 3.3V/1A Output Regulator 1N4148 0.068 F 0.047 F + 3.3 F 470pF 3300pF 1k Figure 11. High Efficiency 8V to 20V Input 3.3V/3A Output Regulator 20V 1N4148 IRFR9024 1 16 PGATE ...
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... NGATE Si9410DY LTC1149 PGND SGND SHDN1 SHUTDOWN – + SENSE SENSE 1000pF *DALE LPE-6562-220MB **KRL SL-1-C1-0R050J LTC1149 LTC1149-3.3/LTC1149-5 + 220 F 35V SENSE 33 H 0.05 V OUT 5V/2A + 220 F 10V 2 AVX 1N5818 1149 F12 + 100 F 25V SENSE 22 H 0.05 V ...
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... LR2010-01-R050-G Figure 15. Logic Selectable 5V/2A or 3.3V/2A High Efficiency Regulator 18 U 1N4148 MTD2955 1 16 PGATE CAP SHDN2 RGND PDRIVE NGATE IRFZ34 LTC1149 PGND SGND SHDN1 SHUTDOWN – + SENSE SENSE 1000pF *HURRICANE LAB HL-KI168M ...
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... Dimensions in inches (millimeters) unless otherwise noted. N Package 16-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 0.045 – 0.065 (1.143 – 1.651) 0.065 (1.651) TYP 0.018 0.003 0.100 0.010 (0.457 0.076) LTC1149 LTC1149-3.3/LTC1149-5 + 1000 F 220 63V 0.1 F 2N2222 MTP30N06EL L* R SENSE 50 H 0.02 IRFZ44 ...
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... LTC1149 LTC1149-3.3/LTC1149-5 PACKAGE DESCRIPTIO 0.010 – 0.020 45 0.053 – 0.069 (0.254 – 0.508) (1.346 – 1.752) 0.008 – 0.010 0 – 8 TYP (0.203 – 0.254) 0.014 – 0.019 0.016 – 0.050 (0.355 – 0.483) 0.406 – 1.270 * DIMENSION DOES NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" ...