ltc3576 Linear Technology Corporation, ltc3576 Datasheet
ltc3576
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ltc3576 Summary of contents
Page 1
... Adjustable Outputs (1A/400mA/400mA I n 180mΩ Internal Ideal Diode + External Ideal Diode Controller Powers the Load in Battery Mode n Li-Ion/Polymer Battery Charger (1.5A Max I n Battery Float Voltage: 4.2V (LTC3576), 4.1V (LTC3576-1) Compact (4mm × 6mm × 0.75mm) 38-pin QFN Package n APPLICATIONS n HDD-Based Media Players n ...
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... TAPE AND REEL LTC3576EUFE#PBF LTC3576EUFE#TRPBF LTC3576EUFE-1#PBF LTC3576EUFE-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. For more information on lead free part marking, go to: For more information on tape and reel specifi cations, go to: ELECTRICAL CHARACTERISTICS temperature range, otherwise specifi ...
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... V > 3.2V VBUS OUT On-the-Go Disabled, V < UVLO BUS (Note 3.8V 0mA (Note 6) OUT VBUS V < 4V and PMOS Switch Off BUS Rising Threshold Hysteresis WALL-BAT Falling Hysteresis Control LTC3576/LTC3576-1 = 3.3V 3.01k, unless CC CLPROG MIN TYP MAX 210 1160 2200 9.6 56 121 667 1217 0.26 0.31 0.41 1 ...
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... V = 5V, BAT = 3.8V BUS CONDITIONS With 6.2k Series Resistor V < V OVSENS OVCUTOFF V > V OVSENS OVCUTOFF OVGATE C = 1nF LOAD LTC3576 LTC3576 PROG PROG V > Suspend Mode, BUS UVLO I = 0μA VOUT 0μA BUS ...
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... Rising OUT OUT f Switching Frequency OSC I FBx Input Current FB1,2,3 D1,2,3 Maximum Duty Cycle R SWx Pull-Down in Shutdown SW1,2,3_PD LTC3576/LTC3576-1 l The denotes the specifi cations which apply over the full operating = 25° 5V, BAT = 3.8V 3.3V BUS CC CONDITIONS 0mA < I < 20mA LDO3V3 ...
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... Maximum Rating condition for extended periods may affect device reliability and lifetime. Note 2: The LTC3576E/LTC3576E-1 are guaranteed to meet performance specifi cations from 0°C to 85°C. Specifi cations over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls ...
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... LOAD CURRENT (mA) PowerPath Switching Regulator Effi ciency vs Load Current 100 90 1x MODE 80 5x, 10x MODE 3576 G07 100 LOAD CURRENT (mA) LTC3576/LTC3576 25°C unless otherwise specifi ed Voltage vs Load Current OUT (Battery Charger Disabled) 4.50 BAT = 4V 4.25 4.00 BAT = 3.4V 3.75 3.50 3.25 4.2 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 LOAD CURRENT (A) ...
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... LTC3576/LTC3576-1 TYPICAL PERFORMANCE CHARACTERISTICS V Quiescent Current vs BUS V Voltage (Suspend) BUS BUS VOLTAGE (V) 3576 G10 Battery Charge Current vs V OUT Voltage 600 R = 3.01k CLPROG PROG 500 5x MODE 400 300 200 100 0 3.65 3.70 3.40 3.45 3.50 3.55 3.60 3.75 V (V) OUT 3576 G13 ...
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... OTG Boost Start-Up into Current Source Load I VBUS 200mA/DIV 0mA V BUS 2V/DIV 3.8V 200μs/DIV 3576 G25 OUT I = 500mA LOAD LTC3576/LTC3576 25°C unless otherwise specifi ed. A OTG Boost Effi ciency vs Load Current 100 700 600 1 10 100 ...
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... LTC3576/LTC3576-1 TYPICAL PERFORMANCE CHARACTERISTICS Battery Charging from USB-HV BUCK-USB V OUT 1V/DIV AC COUPLED V BUS 100mV/DIV AC COUPLED V SW 5V/DIV 0V HVOK 5V/DIV 500μs/DIV BUS HV = 12V IN USING LT3653 OVP Connect Waveform V BUS 5V/DIV OVGATE 5V/DIV OVP INPUT VOLTAGE STEP 5V/DIV 500μs/DIV ...
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... 2.5V IN3 OUT1 1.2V OUT1 1.8V OUT1 0 100 85 LOAD CURRENT (mA) LTC3576/LTC3576 25°C unless otherwise specifi ed. A Battery Drain Current vs Battery Voltage 0mA VOUT BUS BUS (SUSPEND MODE) 3576 G38 5 0 3.0 3.3 3.6 2.7 ...
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... LTC3576/LTC3576-1 TYPICAL PERFORMANCE CHARACTERISTICS Switching Regulator Constant Frequency Quiescent Currents 8 SWITCHING 7 REGULATOR SWITCHING 3 REGULATORS – –40 35 TEMPERATURE (°C) 3576 G46 Switching Regulators 1, 2 Feedback Voltage vs Load Current 0.820 Burst Mode 0.815 OPERATION 0.810 PULSE-SKIP MODE 0.805 ...
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... BUS enhance the pass transistor overvoltage condition is detected, OVGATE is brought rapidly to GND to prevent damage to the LTC3576/LTC3576-1. OVGATE works in conjunction with OVSENS to provide this protection. OVSENS (Pin 6): Overvoltage Protection Sense Input. OVSENS should be connected through a 6.2k resistor to the input power connector and the drain of an external N-channel MOS pass transistor ...
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... LTC3576/LTC3576-1 PIN FUNCTIONS DV (Pin 12): Logic Supply for the I CC serial port is not needed, it can be disabled by grounding DV . When DV is grounded, the default values. See Table 3. SCL (Pin 13): Clock Input Pin for the logic levels are scaled with respect to DV ...
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... ACPR (Pin 28): External Power Source Present Output (Active Low). ACPR indicates that the output of the external high voltage step-down switching regulator is suitable for use by the LTC3576/LTC3576-1. It should be connected to the gate of an external P-channel MOSFET whose source is connected to V and whose drain is connected to OUT WALL ...
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... LTC3576/LTC3576-1 BLOCK DIAGRAM OVSENS 6 OVP OVGATE BUS V 34 BUS CLPROG 1 NTCBIAS 3 BATTERY TEMPERATURE MONITOR NTC 4 CHRG 30 CHARGE STATUS I LIM DECODE LOGIC I 37 LIM0 I 38 LIM1 ENOTG 11 EN1 10 EN2 22 EN3 SDA 14 SCL CONTROL 2.25MHz BIDIRECTIONAL PowerPath ...
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... HD,DAT HD,STA t SP REPEATED START t f CONDITION R/W SUB-ADDRESS ACK LTC3576/LTC3576-1 t BUF t SU,STO 3208 F05 STOP START CONDITION CONDITION INPUT DATA BYTE ACK STOP ...
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... USB, wall adapters, or other 5V sources and provides power to the application and effi ciently charges the battery using Bat-Track. Because power is conserved the LTC3576/LTC3576-1 allow the load current on V exceed the current drawn by the USB port making maxi- mum use of the allowable USB power for battery charging. ...
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... V C – + – – Bat-Track HV CONTROL PWM AND GATE DRIVE CONSTANT CURRENT CONSTANT VOLTAGE BATTERY CHARGER 0.3V – – + 3.6V V VOLTAGE OUT CONTROLLER LTC3576/LTC3576-1 exceeds the programmed power from V 27 WALL – V ACPR OUT 3. BAT + 0.3V 4. OUT 33 IDEAL DIODE + IDGATE OPTIONAL EXTERNAL OmV 31 IDEAL DIODE PMOS – ...
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... CLPROG I I • h VBUS VBUSQ CLPROG R CLPROG where I is the quiescent current of the LTC3576/ VBUSQ LTC3576- the CLPROG servo voltage in CLPROG current limit the value of the programming CLPROG resistor and h is the ratio of the measured cur- CLPROG rent the sample current delivered to CLPROG. ...
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... OUT connected from CLPROG to GND. With a 3.01k resistor on CLPROG, the bidirectional switching regulator has an output current limit of 680mA. As the output current ap- proaches this limit CLPROG servos to 1.15V and V LTC3576/LTC3576-1 27 WALL – ACPR OUT ...
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... When high voltage is applied to the external regulator, WALL will rise toward this programmed output voltage. When WALL exceeds approximately 4.3V, ACPR 22 is brought low and the Bat-Track control of the LTC3576/ there may not OUT LTC3576-1 overdrives the local V high voltage step-down switching regulator. Therefore, ...
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... MOSFET will be in full conduction. To supplement the internal ideal diode, an external P-channel MOSFET may be added from BAT to V IDGATE pin of the LTC3576/LTC3576-1 drives the gate of the external P-channel MOSFET for automatic ideal diode control. The source of the external P-channel MOSFET ...
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... LTC3576/LTC3576-1 OPERATION to charge at the full programmed rate. The external load will always be prioritized over the battery charge current. Likewise, the USB current limit programming will always be observed and only additional power will be available to charge the battery. When system loads are light, battery charge current will be maximized ...
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... YES STOP CHARGING YES BAT RISING CHRG HIGH-Z THROUGH V RECHRG NO BAT FALLING YES THROUGH BAT < V RECHRG V RECHRG YES NO LTC3576/LTC3576-1 INHIBIT CHARGING PAUSE EVENT TIMER YES CHRG CURRENTLY HIGH-Z NO INDICATE NTC FAULT AT CHRG < C/10 BAT YES CHRG HIGH-Z NO 3576 FLOW ...
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... As the temperature drops, the resistance of the NTC thermistor rises. The LTC3576/LTC3576-1 are also designed to pause charging when the value of the NTC thermistor increases to 3.25 times the value of R25. For a Vishay Curve 1 100k thermistor, this resistance, 325k, corresponds to approximately 0° ...
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... The benefi the LTC3576/ LTC3576-1 thermal regulation loop is that charge current can be set according to actual conditions rather than ...
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... It must be 0 for the LTC3576/LTC3576-1 to recognize the address since they are write only devices. Thus the address byte is 0x12. If the correct seven bit ad- dress is given but the R/W bit is 1, the LTC3576/LTC3576-1 will not respond. Sub-Addressed Writing The LTC3576/LTC3576-1 have four command registers for control input ...
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... OPERATION Input Data Table 3 illustrates the four data bytes that may be written to the LTC3576/LTC3576-1. The fi rst byte at sub-address 0 controls the servo volt- age for switching regulators 1 and 2. The second byte at 2 Table Serial Port Mapping Switching Regulator 1 Voltage ...
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... Shutdown Mode The bidirectional USB switching regulator in step-down mode is enabled whenever V LTC3576/LTC3576-1are not in one of the two USB suspend modes (500μA or 2.5mA). When power is available from both the USB and auxiliary inputs, the auxiliary input is given priority and the USB switching regulator is disabled. ...
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... To suit a variety of applications, selectable mode functions can be used to trade off noise for effi ciency. Three modes are available to control the operation of the LTC3576/LTC3576-1’s general purpose switching regulators. At moderate to heavy loads, the pulse skip mode provides the lowest noise switching solution ...
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... P-channel MOSFET and the inductor. Step-Down Switching Regulator Low Supply Operation The LTC3576/LTC3576-1 incorporate an undervoltage lockout circuit on V which shuts down the general OUT ...
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... Bidirectional PowerPath Switching Regulator V and V Bypass Capacitor Selection OUT The type and value of capacitors used with the LTC3576/ LTC3576-1 determine several important parameters such as regulator control-loop stability and input voltage ripple. Because the LTC3576/LTC3576-1 use a bidirectional switching regulator between V current waveform contains high frequency components. ...
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... DCR losses, and will not give the best effi ciency. V OUTx The choice of which style inductor to use often depends C OUT more on the price vs size, performance and any radiated EMI requirements than on what the LTC3576/LTC3576-1 require to operate. 3576f ...
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... Lower inductor values will cause the Burst Mode switching frequency to increase. Table 8 shows several inductors that work well with the LTC3576/LTC3576-1’s general purpose regulators. These inductors offer a good compromise in current rating, DCR and physical size. Consult each manufacturer for detailed information on their entire selection of inductors ...
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... MN1’s BVDSS and reverse voltage protection up to MP1’s BVDSS. Battery Charger Over Programming The USB high power specifi cation allows for drawn from the USB port. The LTC3576/LTC3576-1’s bidirectional switching regulator in step-down mode 36 USB/WALL ...
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... PROG 2π • 100kHz • C PROG Alternate NTC Thermistors and Biasing The LTC3576/LTC3576-1 provide temperature qualifi ed charging if a grounded thermistor and a bias resistor are connected to NTC. By using a bias resistor whose value is equal to the room temperature resistance of the thermistor (R25) the upper and lower temperatures are pre-programmed to approximately 40° ...
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... V observe voltage overshoot on V LTC3576/LTC3576 lab power supply if the overvoltage protection circuit is not used. This overshoot is caused by the inductance of the long leads from the power supply to V ...
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... OUT duration of the current pulse. More capacitance will only decrease the maximum level that V given current pulse. Figure 11 shows an on-the-go device using the LTC3576/ LTC3576-1 acting as the A device. Additional capacitance can be placed on the V when using the overvoltage protection circuit device ...
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... V of the LTC3576/LTC3576-1. Board Layout Considerations The Exposed Pad on the backside of the LTC3576/ LTC3576-1 package must be securely soldered to the PC board ground. This is the primary ground pin in the pack- age, and it serves as the return path for both the control circuitry and the N-channel MOSFET switches ...
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... These capacitors provide the AC current to the internal power MOSFETs and their drivers critical to minimize inductance from these capacitors to the LTC3576/LTC3576-1 and external step- down switching regulator. 3. Connections between the step-down switching regulator (both internal and external) inductors and their respective output capacitors should be kept as short as possible. Use area fi ...
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... V V BUS OUT C3 31 22μF OVGATE IDGATE 32 0805 OVSENS BAT + NTCBIAS Li-Ion NTC 8 PROG V IN1 L2 CLPROG 4.7μH 9 SW1 1.02M 7 FB1 324k LTC3576/LTC3576-1 24 LDO3V3 V IN2 4.7μH 23 SW2 1.02M CHRG 25 FB2 365k IN3 L4 2μH 17 SW3 EN1 751k EN2 20 FB3 ...
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... EN3 11 806k ENOTG 37 I LIM0 38 21 RST3 I LIM1 C1, C3: TAYIO YUDEN JMK212BJ226MG D1: DIODES INC. DFLS240L L1: TAIYO YUDEN NP06DZB6R8M L2: COILCRAFT LPS4018-332LM L3, L4: TOKO 1098AS-4R7M LTC3576/LTC3576-1 L1 22μF 499k 100k TO OTHER LOADS C3 22μF 2.2k 0805 1.76V TO 3.3V 400mA 10pF 1μF 10μF 1.61V TO 3.03V 400mA I/O 1μ ...
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... V V BUS OUT 31 IDGATE M3 32 OVGATE BAT + Li-Ion OVSENS 30 CHRG NTCBIAS 8 V IN1 NTC 9 PROG SW1 L3 CLPROG 1.02M 4.7μH 7 FB1 324k LTC3576/LTC3576-1 16 SDA V IN3 22 SCL EN2 17 DV SW3 CC L5 751k 2μH 20 FB3 806k LDO3V3 21 RST3 24 V IN2 10 EN1 23 SW2 EN3 L4 1.02M 4.7μ ...
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... FB3 EN3 806k ENOTG I LIM0 21 RST3 I LIM1 C1, C3: TAYIO YUDEN JMK212BJ226MG D1: DIODES INC. DFLS140 L1: COILCRAFT MSS6132-472MLC L2: COILCRAFT LPS4018-332LM L3, L4: TOKO 1098AS-4R7M L5: TOKO 1098AS-2R0M LTC3576/LTC3576-1 22μF TO OTHER LOADS C3 22μF 0805 1.76V TO 3.3V 400mA MEMORY 10pF 1μF 10μF 1.61V TO 3.03V 400mA I/O 1μF 10pF 10μ ...
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... OUT IDGATE C 32 BAT + 6 Li-Ion OVSENS 30 3 CHRG NTCBIAS 8 V IN1 4 L2 NTC 4.7μ PROG SW1 1 CLPROG 7 3.01k FB1 LTC3576/LTC3576 LDO3V3 V IN2 4.7μH 23 SW2 25 FB2 IN3 L4 2μ SW3 EN1 22 EN2 20 19 FB3 ...
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... BSC 4.40 REF 5.10 ± 0.05 6.50 ± 0.05 RECOMMENDED SOLDER PAD PITCH AND DIMENSIONS APPLY SOLDER MASK TO AREAS THAT ARE NOT SOLDERED R = 0.10 0.75 ± 0.05 TYP 4.40 REF 0.200 REF 0.00 – 0.05 LTC3576/LTC3576-1 0.70 ±0.05 PACKAGE OUTLINE PIN 1 NOTCH R = 0.30 OR 0.35 45° CHAMFER 2.40 REF 37 38 0.40 ± 0. 4.65 ± 0.10 2.65 ± 0.10 (UFE38) QFN 0707 REV ...
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... BUS 22μF BUS OUT 0805 5 OVGATE BAT 6.2k 6 OVSENS LTC3576/LTC3576-1 2 PROG LDO3V3 1μF CLPROG 300k M2 11 ENOTG POWERS UP WHEN ID PIN HAS LESS THAN 10Ω TO GND (MICRO-A PLUG CONNECTED) L2: COILCRAFT LPS4018-332LM M1: FAIRCHILD FDN372S M2: SILICONIX Si2333DS COMMENTS Maximizes Available Power from USB Port, Bat-Track, 1.5A Max Charge Current, 180mΩ ...