LTC1148HV Linear Technology, LTC1148HV Datasheet
LTC1148HV
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LTC1148HV Summary of contents
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... U A PPLICATI S Notebook and Palmtop Computers Portable Instruments Battery-Operated Digital Devices Cellular Telephones DC Power Distribution Systems GPS Systems O U TYPICAL A PPLICATI V (5.2V TO 18V P-DRIVE LTC1148HV NORMAL SHUTDOWN >1.5V = SHUTDOWN + SENSE I TH – SENSE N-DRIVE SGND PGND 470pF C C 3300pF Figure 1 ...
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... BSOLUTE (Note 1) Input Supply Voltage (Pin 3) LTC1148 and LTC1148L Series ............ 16V to – 0.3V LTC1148HV Series ............................... 20V to – 0.3V Continuous Output Current (Pins 1, 14) .............. 50mA Sense Voltages (Pins 7, 8) LTC1148HV (Adjustable Only) V 12.7V ...................................... 13V to – 0. < 12.7V ......................... (V IN Operating Ambient Temperature Range ...... Extended Commercial Temperature Range ............................... – ...
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... Normal Mode Sleep Mode Sleep Mode Shutdown LTC1148L Series Normal Mode Sleep Mode Shutdown V – V Current Sense Threshold Voltage 8 7 LTC1148, LTC1148HV, LTC1148L (Note 4) LTC1148-3.3, LTC1148HV-3.3, LTC1148L-3.3 V LTC1148-5, LTC1148HV-5 V Shutdown Pin Threshold 10 t Off Time (Note 5) OFF LTC1148-3.3/LTC1148 10V 0V, unless otherwise noted ...
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... LTC1148L version is tested with external feedback resistors resulting in a nominal output voltage of 2.5V. Note 5: In applications where R and power A time increases approximately 40 C/W) Note 6: The LTC1148, LTC1148HV and LTC1148L series are not tested 110 C/W) and not quality assurance sampled at –40 C and 85 C. These J ...
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W U TYPICAL PERFOR A Gate Charge Supply Current 100nC 50nC 140 200 260 OPERATING FREQUENCY (kHz) LTC1148 ...
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LTC1148 LTC1148-3.3/LTC1148 CTIO AL DIAGRA SGND 11 SLEEP + S – – TH2 TH1 + TEST CIRCUIT + V IN 390pF 10nF 3300pF Pin 9 connection shown for LTC1148-3.3 ...
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U OPERATIO The LTC1148 series uses a current mode, constant off- time architecture to synchronously switch an external pair of complementary power MOSFETs. Operating fre- quency is set by an external capacitor at the timing capacitor Pin 4. The output ...
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LTC1148 LTC1148-3.3/LTC1148 APPLICATIO S I FOR ATIO The basic LTC1148 series application circuit (fixed output versions) is shown in Figure 1. External compo- nent selection is driven by the load requirement, and begins with the selection of R ...
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U U APPLICATIO S I FOR ATIO 1000 V SENSE – 800 600 400 V = 12V 200 0 0 200 100 FREQUENCY (kHz) Figure 3. Timing Capacitor Value V 1 OUT ...
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... LTC1148 LTC1148-3.3/LTC1148 APPLICATIO S I FOR ATIO level threshold MOSFETs (V GS(TH) recommended. The LTC1148/LTC1148HV series supply voltage must always be less than the absolute maximum V ratings for the MOSFETs. GS The maximum output current I determines the R MAX requirement for the two MOSFETs. When the LTC1148 ...
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U U APPLICATIO S I FOR ATIO In surface mount applications multiple capacitors may have to be paralleled to meet the capacitance, ESR, or RMS current handling requirements of the application. Aluminum electrolytic and dry tantalum capacitors are both available ...
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LTC1148 LTC1148-3.3/LTC1148 APPLICATIO S I FOR ATIO LTC1148 DC supply current is 160 A for no load, and increases proportionally with load constant 1.6mA after the LTC1148 series has entered continu- ous mode. Because the ...
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U U APPLICATIO S I FOR ATIO and = = 0.007(63 – 25) = 0.27. The required for each MOSFET can now be calculated: 12(0.25) P- 0.12 DS(ON) 2 5(2) (1.27) 12(0.25) N-Ch R ...
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LTC1148 LTC1148-3.3/LTC1148 APPLICATIO S I FOR ATIO With the addition of R3, a current is generated through R1 causing an offset of OFFSET OUT > 25mV, the minimum threshold ...
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U U APPLICATIO S I FOR ATIO Board Layout Checklist When laying out the printed circuit board, the following checklist should be used to ensure proper operation of the LTC1148 series. These items are also illustrated graphi- cally in the ...
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... C R 220 0.01 F 0.033 = *COILTRONICS CTX50-2-MP V OUT **KRL SL-1-C1-0R033J VALUES SHOWN FOR V Figure 12. High Efficiency Adjustable 3A Regulator 1/2 Si4532 D1 MBRS140T3 1/2 Si4532 1 14 P-DRIVE N-DRIVE LTC1148HV-3 PGND SGND INTV SHUTDOWN SHUTDOWN – + ...
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TYPICAL APPLICATIO 270pF Figure 13. 5V Input Voltage, 3.3V/2A Low Dropout, High Efficiency Regulator + C T 10nF 560pF U MMSF3P02HD 14 1 P-DRIVE N-DRIVE LTC1148L-3.3 3 ...
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LTC1148 LTC1148-3.3/LTC1148-5 TYPICAL APPLICATIO S C 270pF NPO 390pF 1N4148 V OUT C C 3300pF Figure 16 14V Input Voltage to 5V/1A Regulator with Current Foldback 18 U Si9803DY 1 ...
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... DIMENSION DOES NOT INCLUDE INTERLEAD FLASH. INTERLEAD 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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... LTC1148 LTC1148-3.3/LTC1148-5 U TYPICAL APPLICATION 220 2N3906 20k 220 2N2222 MUR110 VN2222LL 1 14 P-DRIVE N-DRIVE LTC1148HV PGND SGND 820pF INTV SHUTDOWN SHUTDOWN 100 8 7 3300pF – + SENSE SENSE ...