LTC3586-2 LINER [Linear Technology], LTC3586-2 Datasheet
LTC3586-2
Related parts for LTC3586-2
LTC3586-2 Summary of contents
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... OUT The LTC3586-2/LTC3586-3 are available in a low profile (0.75mm) 38-pin 4mm × 6mm QFN package. L, LT, LTC, LTM, Burst Mode, 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 ...
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... Consult LTC Marketing for information on non-standard lead based finish parts. For more information on lead free part marking, go to: http://www.linear.com/leadfree/ For more information on tape and reel specifications, go to: http://www.linear.com/tapeandreel/ LTC3586 PRODUCT OPTIONS OPTIONS FLOAT VOLTAGE (V LTC3586 4.2V LTC3586-1 4.1V LTC3586-2 4.2V LTC3586-3 4.1V 2 PIN CONFIGURATION , I LIM0 I ...
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... Rising Threshold Falling Threshold Rising Threshold Falling Threshold 1x, 5x, 10x Modes, 0V < BAT < 4.2V 0mA, Battery Charger Off VOUT USB Suspend Mode 250µA VOUT 1x, 5x Modes 10x Mode LTC3586-2 LTC3586-2 LTC3586-3 LTC3586 PROG PROG V > 0µA BUS UVLO ...
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... LTC3586-2/LTC3586-3 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are 5V 1k 3.01k, unless otherwise noted. OUT4 PROG CLPROG SYMBOL PARAMETER V Trickle Charge Threshold Voltage TRKL ∆V Trickle Charge Hysteresis Voltage TRKL V Recharge Battery Threshold Voltage RECHRG t Safety Timer Termination TERM ...
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... R V Pull-Down in Shutdown VOUT3 OUT3 D Maximum Buck Duty Cycle BUCK(MAX) D Maximum Boost Duty Cycle BOOST(MAX) t Soft-Start Time SS3 LTC3586-2/LTC3586-3 The denotes the specifications which apply over the full operating l = 25° 5V, BAT = 3.8V BUS IN1 CONDITIONS V Connected to V Through ...
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... LTC3586-2/LTC3586-3 ELECTRICAL CHARACTERISTICS temperature range, otherwise specifications are 5V 1k 3.01k, unless otherwise noted. OUT4 PROG CLPROG SYMBOL PARAMETER Switching Regulator 4 (Boost) I Input Current VIN4 I Q-Current Drawn from Boost Output VOUT4 I NMOS Switch Current Limit LIMF4 V Output Voltage Adjust Range ...
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... CLPROG 1x USB SETTING, BATTERY CHARGER SET FOR 1A 0 4.2 2.7 3.0 3.3 3.6 3.9 BATTERY VOLTAGE (V) 100 5x, 10x MODE 70 60 0.1 1 358623 G07 LTC3586-2/LTC3586 25°C unless otherwise noted) A Output Voltage vs Output Current (Battery Charger Disabled) 4.50 BAT = 4V 4.25 4.00 BAT = 3.4V 3.75 3.50 3.25 4.2 0 200 400 600 OUTPUT CURRENT (mA) 358623 G02 Battery Drain Current ...
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... LTC3586-2/LTC3586-3 TYPICAL PERFORMANCE CHARACTERISTICS V Current vs V Voltage BUS BUS (Suspend VOLTAGE (V) BUS 358623 G09 3.3V LDO Output Voltage vs Output Current BUS 3.4 BAT = 3.5V BAT = 3.9V , 4.2V BAT = 3.4V BAT = 3.6V 3.2 3.0 BAT = 3V 2.8 BAT = 3.1V BAT = 3.2V BAT = 3.3V 2 OUTPUT CURRENT (mA) ...
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... V = 1.2V OUT1 1.8V OUT1 3.8V IN1, 2 100 1000 358623 G23 LTC3586-2/LTC3586 25°C unless otherwise noted) A CHRG Pin Current vs Voltage (Pull-Down State) 100 BUS BAT = 3. CHRG PIN VOLTAGE (V) 358623 G18 ...
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... LTC3586-2/LTC3586-3 TYPICAL PERFORMANCE CHARACTERISTICS Switching Regulators 1, 2 Load Regulation 1.2V OUT1, 2 1.230 V = 3.8V BUS Burst Mode OPERATION 1.215 1.200 PULSE-SKIPPING MODE 1.185 1.170 0 100 OUTPUT CURRENT (mA) 358623 G25 Buck-Boost Regulator Efficiency vs I LOAD 100 90 Burst Mode 80 OPERATION PWM MODE 70 CURVES ...
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... G36 V OUT4 100mV/DIV T = 90°C AC- COUPLED T = –45°C 300mA I VOUT4 125mA/DIV 50mA 3.6 3.9 4.2 4.5 V (V) IN4 358623 G38 LTC3586-2/LTC3586 25°C unless otherwise noted.) A Boost Efficiency vs V IN4 100 0.7 90 0 0 0 2.6 3 3.4 3.8 4.2 1000 ...
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... LTC3586-2/LTC3586-3 PIN FUNCTIONS (Pins 1, 2): Logic Inputs. I LIM0 LIM1 control the current limit of the PowerPath switching regulator. See Table 1. Table 1. USB Current Limit Settings ( USB SETTING LIM1 LIM0 Mode (USB 100mA Limit 10x Mode (Wall 1A Limit) ...
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... Output Voltage of the Switching PowerPath OUT Controller and Input Voltage of the Battery Charger. The majority of the portable product should be powered from V . The LTC3586-2/LTC3586-3 will partition the available OUT power between the external load on V battery charger. Priority is given to the external load and . A 1µF any extra power is used to charge the battery ...
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... LTC3586-2/LTC3586-3 BLOCK DIAGRAM 35 BUS CLPROG 4 BATTERY NTC 5 TEMPERATURE MONITOR CHRG 30 CHARGE STATUS FAULT 38 FAULT LOGIC EN1 21 EN2 20 EN3 18 EN4 33 MODE LIM0 I 2 LIM1 V 22 IN4 OUT4 SW4 8 FB4 10 14 2.25MHz PowerPath SWITCHING REGULATOR SUSPEND LDO 500µA – ...
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... USB power. Because power is conserved, the LTC3586-2/LTC3586-3 allow the load current on V exceed the current drawn by the USB port without exceed- ing the USB load specifications. ...
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... OUT as OUT When an external P-channel MOSFET transistor is pres- ent, the GATE pin of the LTC3586-2/LTC3586-3 drive its gate for automatic ideal diode control. The source of the external P-channel MOSFET should be connected to V and the drain should be connected to BAT. Capable of driving a 1nF load, the GATE pin can control an external P-channel MOSFET transistor having an on-resistance of 40mΩ ...
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... OPERATION Suspend LDO If the LTC3586-2/LTC3586-3 are configured for USB sus- pend mode, the switching regulator is disabled and the suspend LDO provides power to the V there is power available This LDO will prevent the BUS battery from running down when the portable product has access to a suspended USB port ...
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... LTC3586-2/LTC3586-3 OPERATION Once the battery voltage is above 2.85V, the battery charger begins charging in full power constant-current mode. The current delivered to the battery will try to reach 1022V Depending on available input power and external PROG load conditions, the battery charger may or may not be able to charge at the full programmed rate ...
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... As the temperature drops, the resistance of the NTC thermistor rises. The LTC3586-2/ LTC3586-3 are also designed to pause charging when the value of the NTC thermistor increases to 3.25 times the value of R25. For Vishay “ ...
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... To suit a variety of applications, selectable mode functions can be used to trade-off noise for efficiency. Two modes are avail- able to control the operation of the LTC3586-2/LTC3586-3’s buck regulators. At moderate to heavy loads, the pulse- skipping mode provides the least noise switching solution. ...
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... RUN EVENT TIMER NO TIMER > 30 MINUTES YES INHIBIT CHARGING INDICATE BATTERY FAULT AT CHRG NO BAT > 2.85V YES Figure 4. Flow Chart for Battery Charger Operation (LTC3586-2) LTC3586-2/LTC3586-3 POWER ON CLEAR EVENT TIMER ASSERT CHRG LOW YES NTC OUT OF RANGE NO BAT > 4.15V BATTERY STATE 2.85V < ...
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... GND 358623 F05 Figure 5. Buck Converter Application Circuit Buck Regulator Operating Modes The LTC3586-2/LTC3586-3’s buck regulators include two possible operating modes to meet the noise/ power needs of a variety of applications. In pulse-skipping mode, an internal latch is set at the start of every cycle which turns on the main P-channel MOSFET switch ...
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... EMI and conducted supply noise. BUCK-BOOST DC/DC SWITCHING REGULATOR The LTC3586-2/LTC3586-3 contain a 2.25MHz constant- frequency voltage-mode buck-boost switching regulator. The regulator provides output load current. The buck-boost can be programmed to a minimum output voltage of 2 ...
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... Burst Mode opera- tion and PWM mode. SYNCHRONOUS BOOST DC/DC SWITCHING REGULATOR The LTC3586-2/LTC3586-3 contain a 2.25MHz constant- frequency current mode synchronous boost switching regulator with true output disconnect feature. The regulator provides at least 800mA of output load current and the output voltage can be programmed maximum of 5V ...
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... OUT IN Output Disconnect and Inrush Limiting The LTC3586-2/LTC3586-3 boost converter is designed to allow true output disconnect by eliminating body diode conduction of the internal PMOS rectifier. This allows zero volts during shutdown, drawing zero current from the input source. It also allows for inrush current limiting at start-up, minimizing surge currents seen by the input supply ...
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... V and V BUS OUT The style and value of capacitors used with the LTC3586-2/ LTC3586-3 determine several important parameters such as regulator control-loop stability and input voltage ripple. Because the LTC3586-2/LTC3586-3 use a buck switching power supply from V current waveform contains high frequency components. ...
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... Primary thermistor bias resistor NOM (see Figure 6a Optional temperature range adjustment resistor (see Figure 6b) The trip points for the LTC3586-2/LTC3586-3’s temperature qualification are internally programmed at 0.349 • V the hot threshold and 0.765 • V Therefore, the hot trip point is set when: R ...
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... NTC_ENABLE 358623 F06a Figure 6. NTC Circuits and R1: NOM – r HOT • R25 2.714 – r • R25 NOM HOT • 100k = 104.2k 2.714 V LTC3586-2/LTC3586-3 BUS NTC BLOCK 0.765 • V BUS – TOO_COLD + – TOO_HOT 0.349 • V BUS + + NTC_ENABLE – 0.017 • V ...
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... USB voltage. To prevent excessive voltage from damaging the LTC3586-2/LTC3586-3 during a hot insertion best to have a low voltage coefficient capacitor at the V the LTC3586-2/LTC3586-3. This is achievable by selecting an MLCC capacitor that has a higher voltage rating than that required for the application ...
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... DCR losses, and will not give the best efficiency. The choice of which style inductor to use often depends more on the price vs size, performance and any radiated EMI requirements than on what the LTC3586-2/LTC3586-3 require to operate. The inductor value also has an effect on Burst Mode operations ...
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... R2 where V is 0.8V. See Figure FB3 Closing the Feedback Loop The LTC3586-2/LTC3586-3 incorporate voltage mode PWM control. The control to output gain varies with operation MANUFACTURER region (buck, boost, buck-boost), but is usually no greater Coilcraft than 20. The output filter exhibits a double pole response www ...
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... LTC3586-2/LTC3586-3 APPLICATIONS INFORMATION The compensation network depicted in Figure 9 yields the transfer function R1• R3 • C1 OUT3 1 • R2 • C2 • C1+ C2 s • R2 • C1• C2 ...
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... PL Printed Circuit Board Layout Considerations In order to be able to deliver maximum current under all conditions critical that the exposed pad on the backside of the LTC3586-2/LTC3586-3 packages be soldered to the PC board ground. Failure to make thermal contact between R1 C OUT the exposed pad on the backside of the package and the copper board will result in higher thermal resistances ...
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... BUS IN1 IN2 IN3 currents on the LTC3586-2/LTC3586-3, tend to find their way along the ground plane in a myriad of paths ranging from directly back to a mirror path beneath the incident path on the top of the board. If there are slits or cuts in the ground plane due to other traces on that layer, the current will be forced to go around the slits ...
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... 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. LTC3586-2/LTC3586-3 for the most recent package drawings. UFE Package 38-Lead Plastic QFN (4mm × ...
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... SW V BUS 34 V OUT 5 31 NTC GATE MP1 29 32 PROG BAT + 4 CLPROG Li-Ion 39 GND 0.1µF 2.94k 30 CHRG 16 OUT3 10pF LTC3586-2 LTC3586-3 330pF 15k LDO3V3 11 FB3 1µF 19 SWCD3 10k L2 2.2µ FAULT SWAB3 14 LIM IN3 L3 4.7µH ...