The ISL6299A is a fully integrated low-cost single-cell Li-Ion or Li-polymer battery charger. The charger accepts two power inputs, usually from a USB (Universal Serial Bus) port and another from a desktop stand. The ISL6299A is an ideal charger for smart handheld devices that require a USB interface. The ISL6299A has a maximum voltage of 28V and 7V for the base and USB inputs respectively. Due to the 28V bracket input rating, low cost, large output tolerance adapters are safe to use. When both inputs are powered, the base input is used to charge the battery. Charge current can be programmed into the bracket input resistor. The charging current at the holder input is also programmable through another external resistor. The charger contains Thermaguard 8482 ; protects the IC from excessive temperature. If the mold temperature is higher than the typical value of 100 °C, the thermal folding function reduces the charging current automatically to prevent the temperature from rising. When the battery voltage is lower than 2.6V, the current is low. The charger has two indicator pins. PPR (Power) when either stand or USB input power is connected. The CHG (charge) pin is also an open-drain output when the charge current is above the minimum current level. when? A charge current below the minimum current pin indicates a logic high signal and the state is latched. The latch will reset on one of the following events: (1) the part is disabled and re-enabled; (2) the selected input source is removed and reapplied, (3) USBON goes low, or (4) the battery pin The voltage is below the charging threshold (about 4.0 volts).

Note: Intersil lead-free + annealed products feature a special lead-free material set; molding compound/mold join material and 100% matte tinplate finish, RoHS compliant and compatible with SnPb and lead-free soldering operations. Intersil's lead-free products are classified as MSLs that meet or exceed the lead-free requirements for temperature IPC/JEDEC J Standard-020 during lead-free peak reflow soldering.

feature

Complete Charger for Single Cell Li-Ion/Polymer Batteries

Dual input power supply for dock and USB

low number of components

integrated through components

Fixed 380mA USB charging current

Programmable Rack Charge Current

Charge Current Thermaguard™ Thermal Protection

The maximum voltage of the base input is 28V

charging indication

Adapter presence indication

When there is no leakage current, the leakage current of the battery is less than 0.5 microampere additional input power

Programmable Charge Terminal Current Input with Bracket Latch

Ambient temperature range: -40°C to 85°C

No external blocking diode required

Lead-free plus annealed (RoHS compliant) available

application

Smart Handheld Device

Mobile phones, PDAs, MP3 players

digital camera

Handheld Test Equipment

Related Literature

Technical Brief TB363 "Handling and Processing Moisture Sensitive Surface Mount Devices (SMDs)"

Technical Brief TB389" PCB Land Pattern Design and QFN Package Surface Mount Guidelines

typical application

A simple charger that receives power from a USB port and desk stand

A Simple Charger With Programmable Charge Current and Wide Input Voltage Range

Absolute Maximum Ratings Thermal Information

Supply voltage (USB). -0.3V to 7V

Supply voltage (CRDL). -0.3V to 28V

Other input voltages (EN, USBON, ICDL, IMIN, BAT). -0.3V to 7V

Open-drain pull-up voltage (PPR, CHG). -0.3V to 7V

Recommended Operating Conditions

Ambient temperature range. -40°C to 85°C

Supply voltage (USB pins). 4.3V to 5.5V

Supply voltage (CRDL pin). 4.3V to 24V

Typical carrier charging current. 300mA to 1A

Typical USB charging current. 380 mA

Thermal resistance θJA (°C/W) θJC (°C/W)

DFN package (Note 1, 2). 40 2.5

Maximum Junction Temperature (Plastic Packaging). 150 degrees Celsius

Maximum storage temperature range. -65°C to 150°C

Maximum lead temperature (10s for soldering). 300 degrees Celsius

CAUTION: Stresses beyond those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. This is a pressure rating and operation of the device under the above or any other conditions stated in the operating section of this specification is not implied.

notes:

1. θJA is measured in free air with components mounted on a highly efficient thermally conductive test board with "direct connect" capability. See Technical Bulletin TB379.

2. For theta-JC, the "case temperature" location is the center of the exposed metal pad on the bottom of the package.

Electrical Specifications Typical values are tested at USB=CRDL=5V and ambient temperature 25°C unless otherwise noted. All guaranteed maximum and minimum values under recommended operating conditions

Electrical Specifications Typical values are tested at USB=CRDL=5V and ambient temperature 25°C unless otherwise noted. All guaranteed maximum and minimum values under recommended operating conditions. (continued)

notes:

3. Select 4.0V VBAT so that the CHG output can be used as an offset comparator output indication. If VBAT is lower than the POR threshold, no output pin is available to indicate.

4. The maximum and minimum limits are guaranteed over an ambient temperature range of -40°C to 70°C.

5. If the integrated circuit under the test device cannot dissipate heat, the charging current will be affected by the thermal folding function.

6. If the junction temperature exceeds 70°C, the constant current will be affected.

7. Guaranteed by characterization or correlation with other tests.

8. Tested at TJ=25°C.

Function pin description

CRDL (pin 1)

Bracket input. This pin is usually connected to the stand power input. The maximum input voltage is 28V. The current at this pin is programmable, and the ICDL pin is up to 1A. When this pin is connected to a power supply, the uncharged current is drawn from the USB pin. A value of 1µF or greater is recommended for decoupling with a ceramic capacitor.

USB (pin 2)

USB input. This pin is usually connected to the USB port power connector. Other power supplies below 5.5V are also acceptable. The charging current of the USB pin is fixed at 380mA typically. Capacitor decoupling is recommended for ceramics of 1µF or greater. It is also recommended to use a 61527 ; resistor with a decoupling capacitor to prevent the USB cable from being plugged in.

PPR (pin 3)

Power indicator. An open-drain output pin when the USB input voltage or CRDL input voltage is above its POR level, whether the charger is enabled or disabled. Otherwise close. This is when the dock or USB power is connected.

CHG (pin 4)

Charging indicator pin. Open-drain output when the charging current from the cradle input is above a programmable IMIN or when the input from the USB is above a fixed charging terminal current threshold. Otherwise close.

EN (pin 5)

Enable logic input. Connect to low or leave floating to start the charger.

Imine (pin 6)

IMIN is a programmable input current at the end of charging. The formula for calculating imine is as follows: If RIMIN is kIMIN only applies to cradle charging. The USB EOC current is fixed as shown in the Electrical Specifications table.

USBON (pin 7)

The USBON pin is a control input to turn off USB charging and can be used if desired. Connect to low or keep floating to turn off USB charging.

Ground (Pin 8) System Ground.

ICDL (pin 9)

The ICDL pin has two functions. The first function is to program the cradle charge current in constant current mode. The voltage at this pin is in constant current mode of the base charger. The constant current mode current is programmed by the following equation:

where RICDL is the resistor connected to the ICDL pin in units of (see Typical Applications). It is recommended to program the charging current between 350mA and 650mA. The second function of the ICDL pin is to monitor the charging current. The voltage at this pin, VICDL, is proportional to the actual charging current, ICHG. The cradle charging current should be programmed to be equal to or higher than the USB current; otherwise, the ICDL pin voltage will be higher than 1.22V in constant current mode when the USB charger is operating. The charger still works but the accuracy of the current monitoring voltage degrades and saturates at about 2.1V.

Bat (Pin 10)

Charger output pin. Connect this pin to a battery pack or battery. A ceramic capacitor of 1µF or greater is recommended for decoupling. The charger relies on the stability of the battery, so the battery should always be connected to the bat.

illustrate

The ISL6299A is designed for a single-cell Li-Ion or Li-polymer battery charging circuit that accepts both a USB port and a desktop stand as its power source. While the charge current from the USB input source is fixed at 380mA, the charge current from the stand input is programmable with a resistor RICDL between 0.1A and 1.0A. Likewise the end-of-charge current for USB is typically fixed at 80mA through a resistor to the cradle input and programmed to be sensitive.

input auto select

When both input sources are present, the charger selects only one source to charge the battery. When the CRDL input is above the POR threshold, CRDL is selected as the power supply. Otherwise the USB input is picked out. If the CRDL input voltage is lower than the battery voltage, but the USB input voltage is higher than the battery voltage, then the USB input is used to charge the battery. The control circuit always disconnects the two internal power supplies from the device before switching from one power supply to the other to avoid cross conduction of the two power mosfets. USB Charge Current The charge current enabled by the logic input of the USBON pin when the USB port is selected as the power source. When USBON is driven to logic low, the charger is disabled. The charging current is fixed at a typical value of 380mA when USBON is pushed to logic high. So USB input, USBON pin functions the same as Enping. The following table describes that USB charging is controlled by the USBON pin and the EN pin:

The USBON pin is equivalent to a logic low floating when left. Typically a P-channel MOSFET for USB input has an rDS(on) of 700m at room temperature. With a 380mA charge current, the typical header chamber is 260mV. Therefore, if the input voltage drops to less than 260mV between the USB pin and the BAT pin, rDS(on) becomes the limiting factor for charging current; the charger turns the constant current off regulation. Cradle charging current Cradle charging current is enabled only by the EN pin. The USBON pin cannot control the cradle charging current. This standoff charges current through a resistor connected externally between the ICDL pin and the GND pin. The current can be calculated using one of the equations given in the ICDL pin description. Two equations are used for stent current calculations, each corresponding to a different current range. The typical rDS(ON) of a P-channel MOSFET for a CRDL input is 600 in a room temperature. When headroom is small between input and output voltages, the actual charging current, similar to a USB case, may be limited by the radio data system (open). On the other hand, if the headroom is large between the input and output voltages, the charging current may be subject to the thermal folding threshold.

float voltage

The float voltage in the constant voltage stage is 4.2V. Float voltage to ambient temperature range from -40°C to 70°C. Trickle Charge Current When the battery voltage is below the voltage VMIN given in the minimum battery voltage, the charger operates in trickle/preconditioning mode, where the charge current is typically 14% of the programmed charge current for the base input. If the power is coming from the USB input, the trickle mode current is about 53mA. End-of-Charge Indication When the charge current is below the IMIN threshold, it can be programmed for base input and fixed for USB input. Once the end-of-charge current is reached, the CHG state will be locked. Latch can be in the following conditions:

1. Parts disabled and re-enabled

2. The selected input source has been removed and reapplied

3. Usborn gets muffled, the USB input

4. The BAT pin voltage is lower than the charging threshold (about 4.0 volts) regardless of the CHG pin state, as long as the input power is attached to the charger.

Power display

When the USB or cradle input voltage is higher than the POR threshold, the open-drain MOSFET inside the PPR pin turns on to indicate the presence of input power. Power Good Range Even if there is a power source, the charger will not be able to provide any current that is output when Power Good is not flowing. The following two conditions together define the power good voltage range:

1. VCDRL or VUSB>VPOR

2. VCDRL or VUSB-VBAT>VOS

where VOS is the offset voltage at the input and output of the voltage comparator, discussed later. VPOR and VOS have hysteresis, as shown in the electrical specification sheet. If the input voltage does not meet the conditions of good power. Thermal fold (Thermaguard™) The thermal fold feature reduces charging current when the internal temperature reaches the thermal fold threshold, typically 100°C. This protects the charger from excessive thermal stress at high input voltages.