LTC4410 USB Power Manager in ThinSOT U FEATURES DESCRIPTIO ■ The LTC®4410 enables simultaneous battery charging and operation of portable USB 1.0 and 2.0 compliant devices while they are connected to a USB port. As the USB peripheral load increases, the LTC4410 proportionally reduces the battery charge current to keep the total current less than 500mA or 100mA, depending on the state of the MODE pin. ■ ■ ■ ■ ■ ■ ■ ■ ■ Manages Total Power Between a USB Peripheral and Battery Charger Minimal Voltage Drop (100mV at 500mA) Ultralow Battery Drain: 1µA Reverse Current Blocking Diode Not Required Undervoltage Lockout Very Few External Components Compatible with Several LTC Linear Battery Chargers Overtemperature Protected Dual Battery Charge Priority Management Low Profile (1mm) SOT-23 Package U APPLICATIO S ■ ■ ■ ■ ■ The LTC4410 includes a USB present output that drives an external P-channel MOSFET to disconnect the battery from the USB peripheral when the USB power is valid. This allows device operation when connected to the USB port, even when the battery is deeply discharged. Other features include reverse current blocking, thermal shutdown and low quiescent current (80µA in 500mA MODE) that is compliant with USB Suspend Mode. Cellular Phones PDAs Digital Cameras MP3 Players Battery Backup Systems The LTC4410 is available in the low profile (1mm) SOT-23 (ThinSOTTM) package. , LTC and LT are registered trademarks of Linear Technology Corporation. ThinSOT is a trademark of Linear Technology Corporation. U TYPICAL APPLICATIO USB Powered Battery Charger and Power Manager 100mA 500mA 4.35V TO 5.5V FROM USB VIN 4.7µF GND LTC4410 CHP OFF ON 4.7µF 200mA USBP IRLML6401 1Ω 3.4k 1% SHDN VCC PROG BAT LTC4053 NTC TIMER System Load Step Response SYSTEM POWER SUPPLY VOUT MODE GND LOAD CURRENT 1M BATTERY CHARGER CURRENT 0mA 440mA 240mA 1-CELL Li-Ion 0.1µF 0mA 4410 TA01 USB LTC4410 MODE MODE 500mA 1 100mA 0 SUSPEND 1 5µs/DIV 4410 TA02 LTC4053 SHDN 1 1 0 sn4410 4410fs 1 LTC4410 W U U U W W W ABSOLUTE MAXIMUM RATINGS PACKAGE/ORDER INFORMATION (Note 1) VIN, VOUT Voltages ...................................... –0.3V to 6V USBP, MODE, CHP Voltage ........................ –0.3V to 6V IVOUT (Note 5) ............................................................ 2A Operating Ambient Temperature Range LTC4410E (Notes 3, 4) ........................–40°C to 85°C Storage Temperature Range ................. – 65°C to 150°C Lead Temperature (Soldering, 10 sec).................. 300°C ORDER PART NUMBER TOP VIEW VIN 1 6 VOUT GND 2 5 CHP MODE 3 LTC4410ES6 4 USBP S6 PACKAGE 6-LEAD PLASTIC TSOT-23 TJMAX = 125°C, θJA = 100°C/W TO 150°C/W DEPENDING ON PC BOARD LAYOUT S6 PART MARKING LTK8 Consult LTC Marketing for parts specified with wider operating temperature ranges. ELECTRICAL CHARACTERISTICS The ● denotes specifications that apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = 5V unless otherwise noted. PARAMETER CONDITIONS MIN ● Operating VIN Range Quiescent Current—Active 100mA Mode (MODE = Low) 500mA Mode (MODE = High) CHP Compliance Voltage MODE = 5V, IVOUT = 500mA MODE = 0V, IVOUT = 0mA Reverse Current VOUT = 4V, VIN = 0V MODE Input Current MODE = 0V MODE = 5V 500 80 0 0 MODE Input High ● MODE Input Low ● USBP Output High 1M Resistor to GND, VIN = 5V USBP Output Low 1M Resistor to VIN, VIN = 3.5V UVLO and USBP Threshold Measured on VIN Rising UVLO and USBP Hysteresis Measured on VIN CHP Output Current MODE = High, IVOUT = 0mA (Note 2) MODE = High, IVOUT = 500mA (Note 2) MODE = High, IVOUT = 500mA, TA ≥ 0°C, (Note 2) MODE = High, IVOUT = 500mA, TA < 0°C, (Note 2) Note 1: Absolute Maximum Ratings are those values beyond which the life of a device may be impaired. Note 2: Current flows out of CHP, voltage at CHP = 0V. Note 3: The LTC4410E is guaranteed to meet performance specifications from 0°C to 70°C. Specifications over the –40°C to 85°C operating temperature range are assured by design, characterization and correlation with statistical process controls. ● ● MAX UNITS 5.5 V 700 125 µA µA 4.0 3.5 V V 1 5 µA 0.1 0.1 5 5 µA µA 0.4 V 1.2 4.8 ● MODE = Low, IVOUT = 0mA (Note 2) MODE = Low, IVOUT = 100mA (Note 2) TYP 4.35 V 4.98 V 20 100 mV 4.05 4.2 4.35 V 80 100 120 mV 470 460 450 0 500 500 500 30 530 540 550 µA µA µA µA 430 370 470 510 µA µA Note 4: This IC includes overtemperature protection that is intended to protect the device during momentary overload conditions. Junction temperature will exceed 125°C when overtemperature protection is active. Continuous operation above the specified maximum operating junction temperature may impair device reliability. Note 5: Based on long-term current density limitations. sn4410 4410fs 2 LTC4410 U W TYPICAL PERFOR A CE CHARACTERISTICS IREF Turn-Off Response CHP Current with ILOAD Step IREF vs VIN (MODE = 0) 400 5V 0V 500mA MODE PIN 500mA LOAD STEP 0mA TA = 25°C 350 300 370µA CHP CURRENT INTO A 3.4k RESISTOR 0mA CHP CURRENT INTO A 3.4k RESISTOR 0mA 1µs/DIV IREF (µA) 500µA 4410 G01 250 200 150 10µs/DIV 100 4410 G02 50 0 0 1 2 3 VIN (V) 4 5 6 4410 G03 IREF vs VCHP (MODE = 0) 450 RDS(ON) vs VIN RDS(ON) vs Temperature 250 176 TA = 25°C 400 TA = 25°C 174 200 350 RDS(ON) (mΩ) 250 200 150 170 168 150 100 166 100 50 164 50 0 1 3 2 4 5 6 162 4.2 4.4 VCHP (V) 4.6 4.8 5.0 VIN (V) 5.4 5.2 4410 G04 Reverse Current vs Temperature 0 –50 –25 0 25 50 TEMPERATURE (°C) 100 4.5 90 4.0 80 3.5 70 3.0 60 2.5 2.0 100 4410 G06 50 40 1.5 30 1.0 20 0.5 10 80 75 ICC vs Temperature 5.0 0 –60 –40 –20 0 20 40 60 TEMPERATURE (°C) 5.6 4410 G05 ICC (µA) 0 REVERSE CURRENT (µA) IREF (µA) 300 RDS(ON) (mΩ) 172 100 4410 G07 0 –60 –40 –20 0 20 40 60 TEMPERATURE (°C) 80 100 4410 G08 sn4410 4410fs 3 LTC4410 U U U PI FU CTIO S VIN (Pin 1): Positive Input Supply. When VIN > 4.2V, the internal undervoltage lockout enables the main switch that connects VIN to VOUT. Bypass VIN with a 10µF ceramic capacitor and a 1Ω resistor in series or use a 10µF capacitor with at least 1Ω minimum ESR. This minimizes the voltage transient that can occur when the input is hot switched. USBP (Pin 4): USB Voltage Present Output. This pin goes high when VIN exceeds the undervoltage lockout threshold (4.2V typical). CHP (Pin 5): Charger Program Output. This pin sources a current that is used by the battery charger to control charge current. VOUT (Pin 6): LTC4410 Output. Bypass this pin with a 10µF or larger X5R ceramic capacitor. This capacitor may be omitted if other circuitry connected to VOUT contains a bypass capacitor. When VOUT > VIN, the internal switch is held off, resulting in very low battery drain current (1µA typical). GND (Pin 2): Signal Ground for the LTC4410. MODE (Pin 3): Mode Select Input. This pin selects the maximum USB port current of either 100mA or 500mA. When MODE is high, the current out of CHP will be IVOUT/ 1000. When MODE is low, the current out of CHP will be IVOUT/1000 + 370µA (typical). W BLOCK DIAGRA VIN 1 M1 ×1 – VB M2 ×1000 BODY SWITCH + R1 370µA MODE 3 R2 S1 USBP – + + R3 – M3 REF 1.25V 4 USBP THERMAL SHUTDOWN 5 6 2 CHP VOUT GND 4410 BD sn4410 4410fs 4 LTC4410 U OPERATIO The LTC4410 manages the total current consumption between a battery charger and a USB portable device. In a system using the LTC4410, a battery charger can be set up to charge at the maximum available current from the USB port without any need to reserve current for the device load. As the USB device current increases, the LTC4410 decreases the battery charge current so as not to exceed the maximum allowable current from the USB port. This allows for simultaneous battery charging and device operation. The LTC4410 can only reduce the battery charge current to zero. It is the responsibility of the USB device load to not exceed the USB power limits. The LTC4410 uses an internal power MOSFET to sense load current. This MOSFET is held off when VOUT > VIN or VIN < 4.2V (typ). A replica of the IVOUT current equal to IVOUT/1000 is sourced out of the CHP pin with an accuracy of ±6%. This current can be summed into the PROG node of a battery charger to reduce the charge current. The LTC4410 is primarily designed to interface with battery chargers that use a program pin to set the maximum charge current, with a charge current to program pin current ratio of 1000:1. The voltage on CHP can be externally monitored to signal overcurrent conditions. When VIN > 4.2V, the internal USB present comparator forces the USBP pin high. This signal can be used to detect when the USB voltage is present and drive an external switch to connect or disconnect a battery from the USB peripheral. The MODE pin controls the state of an internal 370µA current reference (IREF). When active (MODE pin low), the total current sourced out of CHP is IVOUT/1000 +IREF. The primary function of the current reference is to offset the battery charger charge current for 100mA mode. When MODE is high, the current reference is disabled. The total current out of CHP with MODE high is IVOUT/1000. The MODE controlled current offset makes it possible to configure the battery charger and the LTC4410 to support the USB specification 1.0 and 2.0 required 100mA and 500mA modes of operation. The low quiescent current (80µA, when MODE is high) of the LTC4410 makes the system easily compliant with the USB specifications 1.0 and 2.0 SUSPEND MODE current consumption requirements. When VOUT > VIN, the LTC4410 transitions to low power mode, draining 1µA (typical) from the Lithium-Ion battery. This condition occurs when the USB device is operating off of its internal battery and not connected to the USB port. sn4410 4410fs 5 LTC4410 U W U U APPLICATIO S I FOR ATIO USB Power Management and Wall Adapter Power when there is no wall adapter. The Schottky diode, D1, is used to prevent USB power loss through R1. If the wall adapter used has more than 500mA capability, a resistor, R3, connected in parallel with R2 using N-channel MOSFET MN1 will increase the charge current when the wall adapter is present. In this example the battery charge current is 340mA without the wall adapter (see the LTC4053 data sheet for details on how to program the battery charge current). When the wall adapter is present, the charge current is 750mA. With the addition of a few components, the LTC4410 allows for simultaneous device operation and battery charging while connected to USB port or wall adapter. The LTC4410 will proportionally reduce the battery charge current to keep the total current within the current rated for the wall adapter. Figure 1 shows an example of how to combine the USB power and wall adapter inputs. A P-channel MOSFET, MP1, is used to prevent back conducting into the USB port when a wall adapter is present. The pull-down resistor, R1, is to assure that MP1 is on ILOAD 100mA 500mA 4.35V TO 5.25V FROM USB MP1 VIN 4.7µF GND 4.7µF LTC4410 CHP USBP 1Ω MP2 R3 4.87k 1% MN1 D1 OFF ON 5V WALL ADAPTER 750mA SHDN VIN R1 1k TIMER 0.1µF SYSTEM POWER SUPPLY VOUT MODE 1M R2 3.4k 1% PROG BAT LTC4053 NTC GND 1-CELL Li-Ion 4410 F01 Figure 1. USB Power Management and Wall Adapter Power sn4410 4410fs 6 LTC4410 U W U U APPLICATIO S I FOR ATIO Dual Battery Charging with Priority current. As BAT1 current demands reduce, the current sourced out of CHP is reduced, enabling BAT2 to have more current. In this example the power supply is a 750mA minimum wall adapter, RPROG (R2 and R3) for the chargers are 2kΩ, resulting in a 750mA charge current. In this application, the total current out of the wall adapter will never exceed 750mA. The LTC4410 can be used to manage two battery chargers, giving one of the chargers (see Figure 2) priority. When BAT1 is being charged, the charge current is flowing through the LTC4410. The LTC4410 is sensing the current and sourcing a current equal to BAT1 charge current/1000 out of CHP. This effectively reduces the BAT2 charger OFF ON VOUT MODE 5V WALL ADAPTER C1 + 4.7µF R1 1Ω OFF ON VIN GND + CHP USBP + C3 4.7µF + TIMER C4 0.1µF LTC4053 PROG NTC GND BAT1 R3 2k R2 2k SHDN VIN C2 0.15µF LTC4410 BAT SHDN VIN TIMER PROG LTC4053 BAT NTC GND BAT2 4410 F02 Figure 2. Priority Dual Battery Charging with Wall Adapter sn4410 4410fs 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 representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. 7 LTC4410 U PACKAGE DESCRIPTIO S6 Package 6-Lead Plastic TSOT-23 (Reference LTC DWG # 05-08-1636) 0.62 MAX 2.90 BSC (NOTE 4) 0.95 REF 1.22 REF 2.80 BSC 1.4 MIN 3.85 MAX 2.62 REF 1.50 – 1.75 (NOTE 4) PIN ONE ID RECOMMENDED SOLDER PAD LAYOUT PER IPC CALCULATOR 0.30 – 0.45 6 PLCS (NOTE 3) 0.95 BSC 0.80 – 0.90 0.20 BSC 0.01 – 0.10 1.00 MAX DATUM ‘A’ 0.30 – 0.50 REF 0.09 – 0.20 (NOTE 3) 1.90 BSC S6 TSOT-23 0302 NOTE: 1. DIMENSIONS ARE IN MILLIMETERS 2. DRAWING NOT TO SCALE 3. DIMENSIONS ARE INCLUSIVE OF PLATING 4. DIMENSIONS ARE EXCLUSIVE OF MOLD FLASH AND METAL BURR 5. MOLD FLASH SHALL NOT EXCEED 0.254mm 6. JEDEC PACKAGE REFERENCE IS MO-193 RELATED PARTS PART NUMBER DESCRIPTION COMMENTS LTC1733 Li-Ion Linear Charger with Thermal Regulation Standalone Charger, No External MOSFET, Diode or Sense Resistor LTC1734 200mA to 700mA Li-Ion Charger in ThinSOT Tiny Design, No Blocking Diode, No Sense Resistor LTC1734L 50mA to 180mA Li-Ion Charger in ThinSOT Tiny Design, High Accuracy for Low Charge Current, No Blocking Diode, No Sense Resistor LTC4053 USB Li-Ion Battery Charger Operates from USB Port, 100mA/500mA Charge Capability, Standalone Charger LTC4054 800mA Li-Ion Battery Charger in ThinSOT Standalone Charger, Thermal Regulation, C/10 Charge Termination LTC4055 USB Power Controller and Li-Ion Linear Charger Load Dependent Charging Guarantees USB Input Current Compliance, Automatic Battery Switchover when Supply is Removed, Tiny 4mm × 4mm QFN Package LTC4412 PowerPathTM Controller in ThinSOT More Efficient than Diode OR’ing, Automatic Switching Between DC Sources, Simplified Load Sharing, 3V ≤ VIN ≤ 28V PowerPath is a trademark of Linear Technology Corporation. sn4410 4410fs 8 Linear Technology Corporation LT/TP 1203 1K • PRINTED IN USA 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com © LINEAR TECHNOLOGY CORPORATION 2002