LTC3577EUFF#PBF Linear Technology, LTC3577EUFF#PBF Datasheet
LTC3577EUFF#PBF
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LTC3577EUFF#PBF Summary of contents
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... QFN package. L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and PowerPath and Bat-Track are trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. Protected by U.S. Patents including 6522118, 6700364, 7511390, 5481178, 6580258 ...
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LTC3577/LTC3577-1 TABLE OF CONTENTS Features ............................................................................................................................ 1 Applications ....................................................................................................................... 1 Typical Application ............................................................................................................... 1 Description......................................................................................................................... 1 Absolute Maximum Ratings ..................................................................................................... 3 Order Information ................................................................................................................. 3 Pin Confi guration ................................................................................................................. 3 Electrical Characteristics ........................................................................................................ 4 Typical Performance Characteristics .........................................................................................10 Pin Functions ...
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... Operating Temperature Range .................–40°C to 85°C Storage Temperature Range .................. –65°C to 125°C ORDER INFORMATION LEAD FREE FINISH TAPE AND REEL LTC3577EUFF#PBF LTC3577EUFF#TRPBF LTC3577EUFF-1#PBF LTC3577EUFF-1#TRPBF Consult LTC Marketing for parts specifi ed with wider operating temperature ranges. Consult LTC Marketing for information on non-standard lead based fi nish parts. ...
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LTC3577/LTC3577-1 ELECTRICAL CHARACTERISTICS full operating temperature range, otherwise specifi cations are INLDO1 INLDO2 IN12 IN3 OUT SYMBOL PARAMETER Input Power Supply V Input Supply Voltage BUS I ...
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ELECTRICAL CHARACTERISTICS full operating temperature range, otherwise specifi cations are INLDO1 INLDO2 IN12 IN3 OUT SYMBOL PARAMETER NTC, Battery Discharge Protection V Cold Temperature Fault Threshold COLD ...
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LTC3577/LTC3577-1 ELECTRICAL CHARACTERISTICS operating temperature range, otherwise specifi cations are at T SYMBOL PARAMETER DV Input Supply Voltage Supply Current DVCC UVLO DVCC,UVLO CC Input HIGH Voltage Input LOW Voltage IL ...
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ELECTRICAL CHARACTERISTICS which apply over the full operating temperature range, otherwise specifi cations are at T all regulators enabled unless otherwise noted. SYMBOL PARAMETER R SW3 Pull-Down in Shutdown SW3_PD 500mA Step-Down Switching Regulator 2 (Buck2 – Pushbutton Enabled, Second ...
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LTC3577/LTC3577-1 ELECTRICAL CHARACTERISTICS full operating temperature range, otherwise specifi cations are at T enabled unless otherwise noted. SYMBOL PARAMETER I Short-Circuit Output Current LDO1_SC V Dropout Voltage (Note 12) DROP1 R Output Pull-Down Resistance in Shutdown LDO1_PD 2 LDO Regulator ...
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ELECTRICAL CHARACTERISTICS over the full operating temperature range, otherwise specifi cations are at T SYMBOL PARAMETER Pushbutton Pin (ON) V Pushbutton Operating Supply Range OUT V UVLO V Falling OUT OUT V Rising OUT ON Threshold Rising V ON_TH ON ...
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LTC3577/LTC3577-1 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 LTC3577E/LTC3577E-1 ...
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TYPICAL PERFORMANCE CHARACTERISTICS Input Current Limit vs Temperature 1200 BUS 1100 R = 2.1k CLPROG 10x MODE 1000 900 800 700 600 5x MODE 500 400 300 200 1x MODE 100 0 – ...
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LTC3577/LTC3577-1 TYPICAL PERFORMANCE CHARACTERISTICS Input Connect Waveform V BUS 5V/DIV V OUT 5V/DIV I BUS 0.5A/DIV I BAT 0.5A/DIV 3577 G13 V = 3.75V 1ms/DIV BAT I = 100mA OUT CLPROG PROG Switching from ...
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TYPICAL PERFORMANCE CHARACTERISTICS Step-Down Switching Regulator 3 1.2V Output Effi ciency vs I OUT3 100 90 Burst Mode 80 OPERATION 70 60 PULSE-SKIPPING MODE 1.2V OUT3 V = 3.8V 10 IN3 ...
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LTC3577/LTC3577-1 TYPICAL PERFORMANCE CHARACTERISTICS OVP Connection Waveform V BUS 5V/DIV OVGATE 5V/DIV OVP INPUT VOLTAGE 500μs/DIV STEP 5V/DIV OVSENS Quiescent Current vs Temperature OVSENS –40 – ...
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TYPICAL PERFORMANCE CHARACTERISTICS LED Driver Effi ciency 6 LEDs 3.6V 4.2V 55 4.8V 5. (mA) LED 3577 G40 DAC Code ...
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LTC3577/LTC3577-1 PIN FUNCTIONS (Pins 1, 2): Input Current Control Pins. I LIM0 LIM1 and I control the input current limit. See Table 1 in the LIM1 “USB PowerPath Controller” section. Both pins are pulled low by a ...
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PIN FUNCTIONS I (Pin 22): Series LED Backlight Current Sink Output. LED This pin is connected to the cathode end of the series LED backlight string. The current drawn through the series LEDs can be programmed via a 6-bit 60dB ...
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LTC3577/LTC3577-1 PIN FUNCTIONS V (Pin 40): USB Input Voltage. V BUS connected to the USB port of a computer output wall adapter. V should be bypassed with a low imped- BUS ance multilayer ceramic capacitor. ACPR (Pin ...
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BLOCK DIAGRAM 8 OVSENS OVERVOLTAGE PROTECTON V BUS 40 CLPROG 43 NTCBIAS 34 BATTERY TEMP NTC MONITOR 35 I LIM0 1 I LIM I LIM1 LOGIC 2 CHRG 44 CHRGE STATUS PWR_ON 14 WAKE 17 PUSH- ON BUTTON 15 INPUT ...
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LTC3577/LTC3577-1 OPERATION PowerPath OPERATION Introduction The LTC3577 is a highly integrated power management IC that features: – PowerPath controller – Battery charger – Ideal diode – Input overvoltage protection – Pushbutton controller – Three step-down switching regulators – High voltage ...
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OPERATION a small voltage above the BAT pin voltage. This control method provides a high input voltage, high effi ciency battery charger and PowerPath function. The LTC3577 also includes a pushbutton input to control the three synchronous step-down switching regulators ...
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LTC3577/LTC3577-1 OPERATION Ideal Diode from BAT to V OUT The LTC3577 has an internal ideal diode as well as a con- troller for an optional external ideal diode. Both the internal and the external ideal diodes respond quickly whenever V ...
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OPERATION 38V (TRANSIENTS 4.7μF TO 60V) LT3480 HIGH VOLTAGE BUCK CIRCUITRY Figure 3. LT3480 Buck Control Using 36V 1μF LT3505 HIGH VOLTAGE BUCK CIRCUITRY Figure 4. LT3505 Buck Control Using V ...
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LTC3577/LTC3577-1 OPERATION HV 7.5V TO 30V (TRANSIENTS TO 60V BOOST IN 0.1μF 4.7μF 10V 8 60V SW DFLS240L LT3653 324k LIM SENSE GND OUT V HVOK C 3 ...
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OPERATION The feedback network of the high voltage buck regulator should be set to generate an output voltage higher than 4.4V (be sure to include the output voltage tolerance of the buck regulator). The V control of the LTC3577 C ...
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LTC3577/LTC3577-1 OPERATION timer is started. After the safety timer expires, charging of the battery will terminate and no more current will be delivered. Automatic Recharge After the battery charger terminates, it will remain off drawing only microamperes of current from ...
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OPERATION High value, low ESR multilayer ceramic chip capacitors reduce the constant-voltage loop phase margin, possibly resulting in instability. Ceramic capacitors up to 22μF may be used in parallel with a battery, but larger ceramics should be decoupled with 0.2Ω ...
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LTC3577/LTC3577-1 OPERATION temperature falls back below the discharge temperature threshold. The battery discharge circuitry is only enabled if the battery voltage is greater than the battery discharge threshold. Alternate NTC Thermistors and Biasing The LTC3577 provides temperature qualifi ed charging ...
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OPERATION By using a bias resistor different in value from R25, NOM the hot and cold trip points can be moved in either direc- tion. The temperature span will change somewhat due to the non-linear behavior of the ...
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LTC3577/LTC3577-1 OPERATION MN1 V1 V2 MN2 Figure 10. Dual Input Overvoltage Protection Each input is protected up to the drain-source breakdown, BVDSS, of MN1 and MN2. R1 must also be rated for the power dissipated during ...
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OPERATION For stability, each LDO output must be bypassed to ground with a minimum 1μF ceramic capacitor (C LDO Operating as a Current Limited Switch The LDO can be used as a current limited switch by simply connecting the LDOx_FB ...
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LTC3577/LTC3577-1 OPERATION open-drain output and requires a pull-up resistor to an appropriate power source. Optimally the pull-up resistor is connected to one of the step-down switching regulator output voltages so that power is not dissipated while the regulators are disabled. ...
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OPERATION increases until it is turned on continuously at 100%. In this dropout condition, the respective output voltage equals the regulator’s input voltage minus the voltage drops across the internal P-channel MOSFET and the inductor. Soft-Start Operation Soft-start is accomplished ...
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LTC3577/LTC3577-1 OPERATION Table 3. Recommended Inductors for Step-Down Switching Regulators INDUCTOR TYPE L (μH) DB318C 4.7 3.3 4.7 D312C 3.3 4.7 DE2812C 3.3 CDRH3D16 4.7 3.3 CDRH2D11 4.7 3.3 CLS4D09 4.7 SD3118 4.7 3.3 SD3112 4.7 3.3 SD12 4.7 3.3 ...
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OPERATION and stability the output capacitor for step-down switching regulators should retain at least 4μF of capacitance over operating temperature and bias voltage. Each switching regulator input supply should be bypassed with a 2.2μF capacitor. Consult with capacitor manufacturers for ...
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LTC3577/LTC3577-1 OPERATION where DAC is the decimal value programmed into the I “LED DAC register”. For example with I DAC[5:0] = 000000 (0 decimal) I LED DAC[5:0] = 111111 (63 decimal) I LED fi nal example DAC[5:0] = 101010 is ...
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OPERATION When dimming via PWM the LED driver and boost converter are both turned on and off together. This allows some degree of additional control over the LED current, and in some cases may offer a more effi cient method ...
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LTC3577/LTC3577-1 OPERATION To keep the average steady-state inductor current below 300mA the maximum output current is reduced as pro- grammed output voltage increases. The output current available is given by: V OUT(MIN) = 300mA • I BOOST(MAX) V BOOST Note ...
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OPERATION ADDRESS START SDA SCL SDA t SU, DAT t LOW SCL t t HIGH HD, STA START t ...
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LTC3577/LTC3577-1 OPERATION Slave Address The LTC3577 responds to a 7-bit address which has been factory programmed to b’0001001[R/W]’. The LSB of the address byte, known as the read/write bit, should be 0 when writing data to the ...
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OPERATION Bits B2, B3, and B4 set the operating modes of the step- down switching regulators (bucks). Writing 1 to any of these three registers will put that respective buck converter in the high effi ciency Burst Mode operation, while ...
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LTC3577/LTC3577-1 OPERATION Table 11 shows the fi nal byte of data that can be written to at sub-address 0x03. This byte of data is referred to as the “LED PWM register”. See the “LED PWM vs Constant Current Operation” section ...
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OPERATION battery has returned to a valid charging temperature bit A0 indicates that charging has entered the end-of- charge state (h ) and is near V C/10 FLOAT has been terminated. Charging can be terminated by reaching ...
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LTC3577/LTC3577-1 OPERATION Upon entering the PUP1 state, the pushbutton circuitry will sequence up the three step-down switching regula- tors in numerical order. LDO1, LDO2 and LED backlight 2 are enabled via I C and do not take part in the ...
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OPERATION Power-Up via External Power Timing The timing diagram, Figure 20, shows the LTC3577 power- ing up through application of the external power (V WALL). For this example the pushbutton circuitry starts in the POFF or HR state with a ...
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LTC3577/LTC3577-1 OPERATION Power-Down via Pushbutton Timing The timing diagram, Figure 22, shows the LTC3577 powering down by μC/μP control. For this example the pushbutton circuitry starts in the PON state with a bat- tery connected and all bucks enabled. In ...
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OPERATION Hard Reset Timing Hard reset provides an ultralow power-down state for shipping or long-term storage as well as a way to power down the application in case of a software lock-up. In the case of software lock- ...
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LTC3577/LTC3577-1 OPERATION LAYOUT AND THERMAL CONSIDERATIONS Printed Circuit Board Power Dissipation In order to be able to deliver maximum charge current under all conditions critical that the exposed ground pad on the backside of the LTC3577 package is ...
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OPERATION The LTC3557 can be used above 20°C, but the charge current will be reduced below 1A. The charge current at a given ambient temperature can be approximated by: 110°C – – BAT ...
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LTC3577/LTC3577-1 TYPICAL APPLICATIONS 5V WALL ADAPTER Si2333DS Si2306BDS D3 R1 6.2k OPTIONAL OVERVOLTAGE/ REVERSE VOLTAGE PROTECTION USB DV CC SDA SCL μC/μP WAKE PBSTAT PWR_ON I LIM0 RST I LIM1 PUSHBUTTON V LDO1 1.2V 75mA 1μF 464k V LDO2 2.5V ...
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TYPICAL APPLICATIONS 38V (TRANSIENTS 150k TO 60V) 4.7μF 68nF 5 40. Si2306BDS USB 6.2k OPTIONAL OVERVOLTAGE PROTECTION DV CC SDA SCL 499k μC/μP WAKE PBSTAT PWR_ON I LIM0 RST I ...
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LTC3577/LTC3577-1 PACKAGE DESCRIPTION 4.50 ±0.05 3.10 ±0.05 2.40 REF 4.00 0.10 PIN 1 TOP MARK (SEE NOTE 6) 7.00 0.10 NOTE: 1. DRAWING IS NOT A JEDEC PACKAGE OUTLINE 2. DRAWING NOT TO SCALE 3. ALL DIMENSIONS ARE IN MILLIMETERS ...
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... Changes to Operation Section Changes to Typical Application Circuits 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 representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC3577/LTC3577-1 ...
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... High Effi ciency USB Power Manager and Battery Charger with Regulated Output Voltage LTC4098 USB-Compatible Switchmode Power Manager with OVP Hot Swap is a trademark of Linear Technology Corporation. 54 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● ...