LT1676CS8#PBF Linear Technology, LT1676CS8#PBF Datasheet
LT1676CS8#PBF
Specifications of LT1676CS8#PBF
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LT1676CS8#PBF Summary of contents
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... At light loads, rise time is deliberately reduced to avoid pulse skipping behavior. The available SO-8 package and 100kHz switching fre- quency allow for minimal PC board area requirements. , LTC and LT are registered trademarks of Linear Technology Corporation. 220 400mA 100 F 36 ...
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LT1676 ABSOLUTE MAXIMUM (Note 1) Supply Voltage ........................................................ 60V Switch Voltage ......................................................... 60V SHDN, SYNC Pin Voltage ........................................... 7V V Pin Voltage ....................................................... 30V CC FB Pin Voltage ........................................................... 3V Operating Junction Temperature Range LT1676C ................................................ 0 ...
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ELECTRICAL CHARACTERISTICS The denotes specifications which apply over the full operating temperature range, otherwise specifications are 48V, V open 5V 1.4V unless otherwise noted SYMBOL PARAMETER Timing f Switching ...
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LT1676 W U TYPICAL PERFORMANCE CHARACTERISTICS SHDN Pin Shutdown Threshold vs Temperature 900 800 700 600 500 400 300 200 50 100 125 –50 – TEMPERATURE ( C) LT1676 G04 Switching Frequency vs Temperature 106 104 102 ...
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PIN FUNCTIONS SHDN (Pin 1): When pulled below the shutdown mode threshold, nominally 0.30V, this pin turns off the regula- tor and reduces V input current to a few tens of micro- IN amperes (shutdown mode). When ...
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LT1676 W BLOCK DIAGRA SHDN 1 BIAS V B SYNC 6 OSC GND 4 BOOST COMP AMP OPERATIO The LT1676 is a current mode switching ...
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U OPERATIO Please refer to the High dV/dt Mode Timing Diagram. A typical oscillator cycle is as follows: The logic section first generates an SWDR signal that powers up the current comparator and allows it time to settle. About 1 ...
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LT1676 U U APPLICATIONS INFORMATION Once the inductance value is decided, inductor peak current rating and resistance need to be considered. Here, the inductor peak current rating refers to the onset of saturation in the core material, although manufacturers sometimes ...
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... V . However, there is finite response C time involved in both the current comparator and turnoff of the output switch. These result in a minimum on time Burst Mode is a trademark of Linear Technology Corporation When combined with the large ratio of V ON(MIN • ...
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LT1676 U U APPLICATIONS INFORMATION oscillator frequency during short-circuit conditions can then maintain control with the effective minimum ON time. A further potential problem with short-circuit operation might occur if the user were operating the part with its oscillator slaved ...
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U U APPLICATIONS INFORMATION frequency resonance problems, proper layout of the com- ponents connected to the IC is essential, especially the power path. B field (magnetic) radiation is minimized by keeping output diode, switch pin and intput bypass capacitor leads ...
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LT1676 U TYPICAL APPLICATIONS V IN 12V TO 48V SHDN LT1676 100pF 63V FB 6 SYNC V C GND 4 C1: PANASONIC HFQ C2: AVX D CASE ...
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U TYPICAL APPLICATIONS Micropower Undervoltage Lockout Certain applications may require very low current drain when in undervoltage lockout mode. This can be accom- plished with the addition of a few more external compo- nents. Figure 6 shows an LTC comparator/reference ...
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LT1676 U TYPICAL APPLICATIONS to maintain proper short-circuit protection. Transistors Q1, Q2 and resistor R7 form a high V current voltage regulator to power U2. Burst Mode Operation Configuration with UVLO Figure 7a uses an external comparator to control the ...
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... FLASH SHALL NOT EXCEED 0.010" (0.254mm) 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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... Operation up to 48V, Controlled Voltage and Current Slew Rates V OUT 5V C2 0mA to 150mA R1 100 F 36.5k 10V 1% R2 12.1k 1% 1676 TA02 FOR 3.3V V VERSION: OUT I : 0mA TO 200mA OUT L1: 150 H, DO1608C-154 R1: 24.3K, R2: 14.7k 1676f LT/TP 0499 4K • PRINTED IN USA LINEAR TECHNOLOGY CORPORATION 1998 ...