LT1767-2.5 LINER [Linear Technology], LT1767-2.5 Datasheet
LT1767-2.5
Related parts for LT1767-2.5
LT1767-2.5 Summary of contents
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... SYNC GND 4.7k *MAXIMUM OUTPUT CURRENT IS SUBJECT TO THERMAL DERATING. LT1767-2.5/LT1767-3.3/LT1767-5 Monolithic 1.5A, 1.25MHz Step-Down Switching Regulators DESCRIPTIO ® The LT 1767 is a 1.25MHz monolithic buck switching regulator. A high efficiency 1.5A, 0.22 switch is included on the die together with all the control circuitry required to complete a high frequency, current mode switching regu- lator ...
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... 17% FB NOM 25V SHDN < V < 25V, 0.4V < V < 0.9V LT1767 (Adj (Note 3) LT1767-1.8 LT1767-2.5 LT1767-3.3 LT1767-5 LT1767 (Adj) ORDER PART NUMBER LT1767EMS8E TOP VIEW LT1767EMS8E-1.8 8 SYNC LT1767EMS8E-2 SHDN LT1767EMS8E-3.3 MS8E PACKAGE LT1767EMS8E-5 MS8E PART MARKING ...
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... W U TYPICAL PERFORMANCE CHARACTERISTICS FB vs Temperature (Adj) 1.22 1.21 1.20 1.19 1.18 –50 – 100 TEMPERATURE ( C) 1767 G01 LT1767-2.5/LT1767-3.3/LT1767-5 CONDITION LT1767-1.8 LT1767-2.5 LT1767-3.3 LT1767-5 0.4V < V < 0. – 17% FB NOM 17% FB NOM Duty Cycle = 1.2V, I ...
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... LT1767/LT1767-1.8/ LT1767-2.5/LT1767-3.3/LT1767 TYPICAL PERFOR A CE CHARACTERISTICS SHDN Threshold vs Temperature 1.40 1.38 1.36 1.34 1.32 1.30 –50 – 100 125 TEMPERATURE ( C) 1767 G04 Minimum Input Voltage for 2.5V Out 3.5 3.3 3.1 2.9 2.7 2.5 0.001 0.01 0.1 LOAD CURRENT (A) 1767 G07 Current Limit Foldback 2.0 1.5 SWITCH CURRENT 1.0 0.5 FB CURRENT 0 0 0.2 0.4 0.6 0.8 1 1.2 FEEDBACK VOLTAGE (V) 1767 G10 ...
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... Keep the ground path short between the GND pin and the load and use a ground plane LT1767/LT1767-1.8/ LT1767-2.5/LT1767-3.3/LT1767-5 when possible. Keep the path between the input bypass and the GND pin short. The GND pin of the MS8 package is directly attached to the internal tab ...
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... LT1767/LT1767-1.8/ LT1767-2.5/LT1767-3.3/LT1767-5 W BLOCK DIAGRAM The LT1767 is a constant frequency, current mode buck converter. This means that there is an internal clock and two feedback loops that control the duty cycle of the power switch. In addition to the normal error amplifier, there is a current sense amplifier that monitors switch current on a cycle-by-cycle basis ...
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... F to 4.7 F are suitable for most applications. Y5V or similar type ceramics can be used since the absolute value LT1767-2.5/LT1767-3.3/LT1767 capacitance is less important and has no significant effect on loop stability ...
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... LT1767/LT1767-1.8/ LT1767-2.5/LT1767-3.3/LT1767 APPLICATIONS INFORMATION Table 2. Surface Mount Solid Tantalum Capacitor ESR and Ripple Current E Case Size ESR (Max, AVX TPS, Sprague 593D 0.1 to 0.3 AVX TAJ 0.7 to 0.9 D Case Size AVX TPS, Sprague 593D 0.1 to 0.3 C Case Size AVX TPS 0.2 (typ) Figure 3 shows a comparison of output ripple for a ceramic and tantalum capacitor at 200mA ripple current ...
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... CDRH5D18-6R2 6.2 1.4 CDRH5D28-100 10 1.3 LT1767-2.5/LT1767-3.3/LT1767 After making an initial choice, consider the secondary things like output voltage ripple, second sourcing, etc. Use the experts in the Linear Technology’s applica- tions department if you feel uncertain about the final choice. They have experience with a wide range of inductor types and can tell you about the latest devel- opments in low profile, surface mounting, etc ...
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... LT1767/LT1767-1.8/ LT1767-2.5/LT1767-3.3/LT1767 APPLICATIONS INFORMATION suitable, but the ESR should be <1 to ensure it can be fully recharged during the off time of the switch. The capacitor value is derived from worst-case conditions of 700ns on-time, 50mA boost current, and 0.7V discharge ripple. This value is then guard banded by 2x for secondary factors such as capacitor tolerance, ESR and temperature effects ...
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... The ground for these components should be separated from the switch current path. Failure will result in poor stability or subharmonic like oscillation. LT1767-2.5/LT1767-3.3/LT1767 Board layout also has a significant effect on thermal resistance. Soldering the exposed pad to as large a copper ...
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... C/W. To calculate die temperature, use the appropriate thermal resistance number and add in worst-case ambient temperature TOT CMDSH-3 C2 0.1 F BOOST OPEN LT1767-2.5 2 SHDN FB HIGH SYNC GND 1.5nF UPS120 ...
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... The LT1767 can be considered as two g error amplifier and the power stage. Figure 8 shows the overall loop response with a 330pF V capacitor and a typical 100 F tantalum output capacitor. The response is set by the following terms: LT1767-2.5/LT1767-3.3/LT1767 LT1767 CURRENT MODE POWER STAGE ...
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... LT1767/LT1767-1.8/ LT1767-2.5/LT1767-3.3/LT1767 APPLICATIONS INFORMATION The zero produced by the ESR of the tantalum output capacitor is very useful in maintaining stability. Ceramic output capacitors do not have a zero due to very low ESR, but are dominated by their ESL. They form a notch in the 1MHz to 10MHz range. Without this zero, the V be made dominant ...
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... 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. LT1767-2.5/LT1767-3.3/LT1767 current in L1A and changes L1B current waveform from square to triangular ...
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... LT1767/LT1767-1.8/ LT1767-2.5/LT1767-3.3/LT1767-5 PACKAGE DESCRIPTION 0.889 0.127 2.794 0.102 (.035 .005) (.110 .004) 5.23 2.083 0.102 3.2 – 3.45 (.206) (.126 – .136) (.082 .004) MIN 0.65 0.42 0.04 (.0165 .0015) (.0256) TYP BSC RECOMMENDED SOLDER PAD LAYOUT NOTE: 1. DIMENSIONS IN MILLIMETER/(INCH) 2. DRAWING NOT TO SCALE 3. DIMENSION DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. ...