LTC1929-PG LINER [Linear Technology], LTC1929-PG Datasheet
LTC1929-PG
Related parts for LTC1929-PG
LTC1929-PG Summary of contents
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... Phase-Lockable Fixed Frequency: 150kHz to 300kHz True Remote Sensing Differential Amplifier TM OPTI-LOOP Compensation Improves Transient Response 1% Output Voltage Accuracy Power Good Output Voltage Monitor (LTC1929-PG) Wide V Range 36V Operation IN Very Low Dropout Operation: 99% Duty Cycle Adjustable Soft-Start Current Ramping Internal Current Foldback ...
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... EXTV INTV CC 9 PGND 20 10 BG2 19 11 BOOST2 18 12 SW2 17 13 TG2 16 14 AMPMD PACKAGE 28-LEAD PLASTIC SSOP *PGOOD ON LTC1929-PG = 125 C/W JMAX unless otherwise noted. MIN TYP 0.792 0.800 0.808 – 5 0.05 – 0.1 0.002 0.84 0.86 3 3.5 3 1.5 470 20 – ...
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... HIGH R PLLIN Input Resistance PLLIN I Phase Detector Output Current PLLFLTR Sinking Capability Sourcing Capability R Controller 2-Controller 1 Phase RELPHS PGOOD Output (LTC1929-PG Only) V PGOOD Voltage Low PGL I PGOOD Leakage Current PGOOD V PGOOD Trip Level PG Differential Amplifier/Op Amp Gain Block (Note 5) A Gain ...
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... Only) DIFFOUT Op Amp Mode (LTC1929 Only) L Note 5: When the AMPMD pin is high (default for the LTC1929-PG), the LTC1929 IC pins are connected directly to the internal op amp inputs. When the AMPMD pin is low, internal MOSFET switches connect four and power A 40k resistors around the op amp to create a standard unity-gain differential amp ...
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... SENSE(CM (V) RUN/SS 1929 G10 LTC1929/LTC1929-PG EXTV Voltage Drop CC 250 200 LTC1929 150 LTC1929-PG 100 CURRENT (mA) 1929 G05 Maximum Current Sense Threshold vs Duty Factor 100 DUTY FACTOR (%) ...
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... LTC1929/LTC1929- TYPICAL PERFOR A CE CHARACTERISTICS Load Regulation 0 15V IN FIGURE 1 –0.1 –0.2 –0.3 –0 LOAD CURRENT (A) 1629 G13 Maximum Current Sense Threshold vs Temperature 80 – SENSE –50 – TEMPERATURE ( C) Soft-Start (Figure 13) V ITH 1V/DIV V OUT 2V/DIV ...
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... TEMPERATURE ( C) V RUN/SS Thresholds vs Temperature 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0 100 125 –50 1929 G23 LTC1929/LTC1929-PG Oscillator Frequency vs Temperature 350 FREQSET 300 250 V = OPEN FREQSET 200 150 FREQSET 100 50 0 125 50 – 50 – TEMPERATURE ( C) 1929 G21 ...
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... OS Amplifier. Internal precision resistors capable of being electronically switched in or out can configure differential amplifier (default for the LTC1929-PG uncommitted Op Amp. AMPMD (Pin 15): (LTC1929 Only) This Logic Input pin controls the connections of internal precision resistors that configure the operational amplifier as a unity-gain differential amplifier ...
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... CTIO AL DIAGRA LTC1929-PG OPTIONAL PGOOD HOOKUP DIFFOUT PGOOD – – PLLIN PHASE DET F IN 50k PLLFLTR R LP CLK1 OSCILLATOR CLK2 C LP LTC1929 ONLY – – AMPMD 0V POSITION DIFFOUT V 0.8V REF 4.7V 5V – EXTV LDO CC REG INTV ...
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... LTC1929/LTC1929-PG U OPERATIO (Refer to Functional Diagram) Main Control Loop The LTC1929 uses a constant frequency, current mode step-down architecture with inherent current sharing. During normal operation, the top MOSFET is turned on each cycle when the oscillator sets the RS latch, and turned off when the main current comparator, I the RS latch ...
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... The AMPMD pin is grounded to connect the internal precision resistors in a unity-gain differencing application (default for the LTC1929-PG), or tied to the INTV bypass the internal resistors and make the amplifier inputs directly available. The amplifier is a unity-gain stable, 2MHz gain-bandwidth, > ...
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... LTC1929/LTC1929- APPLICATIO S I FOR ATIO When using the controller in very low dropout conditions, the maximum output current level will be reduced due to internal compensation required to meet stability criterion for buck regulators operating at greater than 50% duty factor. A curve is provided to estimate this reduction in peak output current level depending upon the operating duty factor ...
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... For V high current efficiency generally improves with larger MOSFETs, while for V increase to the point that the use of a higher R with lower C volt- CC Kool registered trademark of Magnetics, Inc. LTC1929/LTC1929-PG GS(TH) , reverse transfer capacitance C DS(ON) V OUT – ...
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... LTC1929/LTC1929- APPLICATIO S I FOR ATIO synchronous MOSFET losses are greatest at high input voltage when the top switch duty factor is low or during a short-circuit when the synchronous switch is on close to 100% of the period. The term ( generally given for a MOSFET in the form of a normalized R vs ...
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... The input supply current should be measured while the controller is operating in continuous mode at maximum V and the power dissipation calculated in order to pre- IN vent the maximum junction temperature from being exceeded. LTC1929/LTC1929-PG pin from the V supply pin. The INTV CC IN pin regulator can supply up to 50mA CC ...
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... LTC1929/LTC1929- APPLICATIO S I FOR ATIO EXTV Connection CC The LTC1929 contains an internal P-channel MOSFET switch connected between the EXTV When the voltage applied to EXTV CC internal regulator is turned off and the switch closes, connecting the EXTV pin to the INTV CC supplying internal and MOSFET gate driving power. The ...
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... This configuration is activated when the AMPMD pin is tied to ground and is the default for the LTC1929-PG. When the AMPMD pin is tied to INTV resistors are disconnected and the amplifier inputs are made directly available. The amplifier can then be used as a general purpose op amp ...
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... LTC1929/LTC1929- APPLICATIO S I FOR ATIO after C reaches 4.1V, C begins discharging on the SS SS assumption that the output overcurrent condition. If the condition lasts for a long enough period as deter- mined by the size the controller will be shut down SS until the RUN/SS pin voltage is recycled. If the overload ...
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... Each time a MOSFET gate is switched from low to high to low again, a packet of charge dQ moves from INTV ground. The resulting dQ/ current out of INTV is typically much larger than the control circuit current. In continuous mode, I are the gate charges of the topside and bottom side MOSFETs. LTC1929/LTC1929- OUT(MAX) IN(MAX) current (in ...
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... LTC1929/LTC1929- APPLICATIO S I FOR ATIO Supplying INTV power through the EXTV CC from an output-derived source will scale the V required for the driver and control circuits by the ratio (Duty Factor)/(Efficiency). For example 20V to 5V application, 10mA of INTV current results in approxi- ...
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... Although the LT1929 has a maximum input voltage of 36V, most applications will be limited to 30V by the MOSFET BV . DSS 50A I RATING 12V LTC1929 TRANSIENT VOLTAGE SUPPRESSOR GENERAL INSTRUMENT 1.5KA24A Figure 8. Automotive Application Protection LTC1929/LTC1929-PG 1929 F08 21 ...
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... LTC1929/LTC1929- APPLICATIO S I FOR ATIO Design Example As a design example, assume (nominal (max 1.8V 20A and f = 300kHz. OUT MAX A The inductance value is chosen first based on a 30% ripple current assumption. The highest value of ripple current occurs at the maximum input voltage. Tie the FREQSET pin to the INTV pin for 300kHz operation ...
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... External OPTI- LOOP compensation allows overcompensation for PC layouts which are not optimized but this is not the recommended design procedure. LTC1929/LTC1929- ceramic decoupling capacitor con- CC and the power ground pin? CC ...
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... LTC1929/LTC1929- APPLICATIO S I FOR ATIO Simplified Visual Explanation of How a 2-Phase Controller Reduces Both Input and Output RMS Ripple Current A multiphase power supply significantly reduces the amount of ripple current in both the input and output capacitors. The RMS input ripple current is divided by, and ...
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... Figure 9. Instantaneous Current Path Flow in a Multiple Phase Switching Regulator CIN I COUT W U SW1 L1 R SENSE1 D1 L2 SW2 R SENSE2 D2 SINGLE PHASE SW1 V SW2 CIN I COUT Figure 10. Single and 2-Phase Current Waveforms LTC1929/LTC1929-PG V OUT C OUT + DUAL PHASE RIPPLE 1929 F10 R L 1929 F09 25 ...
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... LTC1929/LTC1929-PG U TYPICAL APPLICATIO S 26 ...
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... DWG # 05-08-1640 – 8 0.65 (0.0256) BSC 0.25 – 0.38 (0.010 – 0.015) LTC1929/LTC1929-PG 40 10.07 – 10.33* (0.397 – 0.407 7.65 – 7.90 (0.301 – 0.311 1.73 – 1.99 (0.068 – 0.078) 0.05 – 0.21 (0.002 – 0.008) ...
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... High Efficiency Synchronous Step-Down Controller LTC1736 High Efficiency Synchronous Step-Down Controller with 5-Bit VID Adaptive Power and Burst Mode are trademarks of Linear Technology Corporation. Linear Technology Corporation 28 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 www.linear-tech.com LTC1929- TG1 26 – ...