LTC1773EMS Linear Technology, LTC1773EMS Datasheet
LTC1773EMS
Specifications of LTC1773EMS
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LTC1773EMS Summary of contents
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... Schottky diode, saving components and board space. The LTC1773 comes in a 10-lead MSOP package. , LT, LTC and LTM are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. OPTI-LOOP and Burst Mode are registered trademarks of Linear Technology Corporation. ...
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... Ramping Up from 0V IN Maximum Current Sense Voltage C = 3000pF (Note 6) LOAD C = 3000pF (Note 6) LOAD C = 3000pF (Note 6) LOAD C = 3000pF (Note 6) LOAD ORDER PART NUMBER 10 SW – LTC1773EMS 9 SENSE PART MARKING 6 BG LTMV = 120°C/W http://www.linear.com/leadfree/ MIN TYP MAX UNITS 20 60 ● 0.788 0.80 ...
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ELECTRICAL CHARACTERISTICS Note 1: Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. Exposure to any Absolute Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC1773 is ...
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LTC1773 W U TYPICAL PERFOR A CE CHARACTERISTICS Maximum Current Sense Threshold vs V RUN/SS 120 100 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 V (V) RUN/SS 1773 G07 Oscillator Frequency vs Temperature 560 ...
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PIN FUNCTIONS I (Pin 1): Error Amplifier Compensation Point. The TH current comparator threshold increases with this control voltage. Nominal voltage range for this pin 1.2V. Under high duty cycle and nearing current limit, ...
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LTC1773 U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC1773 uses a constant frequency, current mode step- down architecture to drive an external pair of comple- mentary power MOSFETs. During normal operation, the external top P-channel power MOSFET ...
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U OPERATIO (Refer to Functional Diagram) and forces the main switch to stay off for the same number of cycles. Increasing the output load current slightly, above the minimum required for discontinuous conduc- tion mode, allows constant frequency PWM. Frequency ...
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LTC1773 U U APPLICATIONS INFORMATION The operating frequency and inductor selection are inter- related in that higher operating frequencies allow the use of smaller inductor and capacitor values. However, oper- ating at a higher frequency generally results in lower efficiency ...
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U U APPLICATIONS INFORMATION V – OUT 1 δ SYNC MAX V IN where δ is the temperature dependency constant inversely related to the gate drive ...
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LTC1773 U U APPLICATIONS INFORMATION The I pin OPTI-LOOP compensation components can be TH optimized to provide stable, high performance transient response regardless of the output capacitors selected. Manufacturers such as Nichicon, United Chemicon and Sanyo should be considered for ...
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U U APPLICATIONS INFORMATION Synchronous switching removes the normal limitation that power must be drawn from the inductor primary winding in order to extract power from auxiliary windings. With continuous synchronous operation, power can be drawn from the auxiliary windings ...
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LTC1773 U U APPLICATIONS INFORMATION Other losses including C and C IN losses, and inductor core losses, generally account for less than 2% total additional loss. Checking Transient Response The regulator loop response can be checked by looking at the ...
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U U APPLICATIONS INFORMATION PC Board Layout Checklist When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the LTC1773. These items are also illustrated graphically in the layout diagram of Figure ...
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LTC1773 U U APPLICATIONS INFORMATION For the selection of the external MOSFETs, the R must be guaranteed at 2.5V since the LTC1773 has to operate down to 2.7V. This requirement can be met by the Si9801DY. For the feedback resistors, ...
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U TYPICAL APPLICATIONS 33pF 200pF LTC1773 30k RUN/SS 0.1µF 3 SYNC/FCB GND 80. SANYO POSCAP 10TPA100M AVX TPSD227M006R0100 OUT Figure 8. Dual Output 2.5V/2A and 5V/100mA ...
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LTC1773 U TYPICAL APPLICATIONS 33pF 200pF 30k RUN/SS 3 0.1µF V SYNC/FCB GND 80. SANYO POSCAP 6TPA150M AVX TPSD227M006R0100 OUT L1: COILTRONICS CTX2-4/BH ELECTRONICS 511-1010 R : ...
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U TYPICAL APPLICATIONS 47pF 220pF 750kHz CLK 100pF 80. OUT L1: SUMIDA CDRH5D28 3R0 R : IRC LR1206-01-R050-J SENSE Figure 11. 750kHz Single Lithium-Ion to 2.5V/1A Regulator 47pF 220pF LTC1773 30k ...
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LTC1773 U TYPICAL APPLICATIONS 47pF 30k 1 220pF 2 0.1µ 100pF 5 80. SANYO POSCAP 6TPA47M IN OUT L1: SUMIDA CDRH5D28 4R2 R : IRC LR1206-01-R068-F SENSE Figure 13. Single Lithium-Ion to 2V/800mA ...
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... MOLD FLASH, PROTRUSIONS OR GATE BURRS SHALL NOT EXCEED 0.152mm (.006") 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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... V OUT1 2. OUT1 47k 150µF 6.3V 1773 TA04 to 0.5A OUT , MS8 Package Q ≤ 10V, 550kHz IN ≤ 9.8V 94% Efficiency IN , 550kHz 600mA,MS8 Q OUT , 550kHz 600mA,MS8 Q OUT = 600mA 3.3V OUT IN LT 1106 REV B • PRINTED IN USA © LINEAR TECHNOLOGY CORPORATION 2006 1773fb ...