Diodes APM8601 User Manual

APM8601

DUAL CHANNEL SINGLE CELL LINEAR LITHIUM BATTERY

CHARGER WITH 28V OVP and PROGRAMMABLE CHARGE

TIMER

Description

The APM8601 is a dual input channel linear Li-Ion charger for portable equipment that is optimized for small form-factor applications.

The charge algorithm in the APM8601 covers all the charge requirements for a single Li-Ion battery cell. Included is pre-charging for deeply discharged cells, constant current / constant voltage fast charging and a top-off feature to bring the cell safely to a full-charge level.

The battery is constantly monitored for overvoltage, charge time and cell temperature to ensure safe charging. A fault is triggered once the charge time exceeds a value that is programmable using a single capacitor and the temperature measurement is achieved through a thermistor positioned close to the battery cell.

The APM8601 automatically selects the USB or DC input, depending on which is valid (DC has priority if both are vali d). The charging current from the USB input is set to 100mA or 500mA based on the logic level of the USEL input.

NEW PRODUCT

The APM8601 is packaged in U-DFN3030-14 package with a thermal pad.

Applications

• Handheld Consumer Devices

• Cell Phones, PDAs, MP3 Players

• Handheld Test Equipment

• Digital Still Cameras

• Multimedia players

Pin Assignments

Figure 1. Pin Out

Features

• Linear Lithium Ion / Lithium Polymer charging IC

• Supply input safe up to 28V

• Fast charging with maximum current of 1A

• 100mA/500mA USB charge current selected with USEL

• Resistor-programmable charging current

• Resistor programmable end-of-charge

• Capacitor programmable charge timer

• Three charge indicator pins for a status display

• Thermal protection

• DFN3030-14: Available in “Green” Molding Compound (No Br, Sb)

• Lead Free Finish/ RoHS Compliant (Note 1)

Note 1. EU Directive 2002/95/EC (RoHS). All applicable RoHS exemptions

applied. Please visit our website at

http://www.diodes.com/products/lead_free.html.

Typical Application Circuit

APM8601

Document number: DS35138 Rev. 1 - 2

Figure 2. Typical Application Circuit

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Pin Descriptions

APM8601

DUAL CHANNEL SINGLE CELL LINEAR LITHIUM BATTERY

CHARGER WITH 28V OVP and PROGRAMMABLE CHARGE

TIMER

NEW PRODUCT

Name Pin # Description

BAT 1, 7

SETI 2

THM 3 Thermistor Input

GND 4 Ground Ground connection.

CT 5 Charge Timing

USEL 6

EN

USB 9 USB Input USB supply input. Connect a bypass capacitor (1µF) from USB to GND.

10

POK

11

CHG

DC 12, 13 DC Input

FLT

EP Exposed Pad

14

Connection to the

Charge Current

8

Charge Status

Battery

programming

USB Charge

Select

Enable

(active-low)

Power OK

(active-low)

Fault Flag

(active-low)

The battery is charged via this pin and the BAT voltage is constantly monitored. Connect a bypass capacitor between BAT and GND (2.2µF).

The maximum charge current is programmed using a resistor from SETI to GND. This also determines the prequal current charging level and top-off threshold.

To monitor the battery temperature, connect a 10kΩ NTC thermistor. Place this thermistor as close as possible to the battery. Connect THM to GND if temperature measurement is not required.

Connecting a capacitor from CT to GND will set the time-outs for prequal, top-off and fast-charge. Connecting CT direct to GND disables these timers.

Logic input to program the charge current in USB charging mode.

= 90mA when USEL = low, and I

I

BAT

The charger is enabled when this input is low. To start the charger connect to GND. Drive this input high to disable the charger.

When a valid input source is connected, this open-drain output is pulled low. Open-drain output that indicates the charging status. It is active only in the fast-

charge state and goes high-impedance when the charger is either disabled or in prequal or top-off mode.

DC supply input. The recommended input voltage is between 4.32V and 7V. This input is capable of withstanding up to 28V. Connect both DC pins together on the PCB. It is recommended to connect a bypass capacitor (1µF) from DC to GND.

If the prequal or fast-charge timers expire and the charging threshold voltage is not reached, power or raise

For optimal thermal performance connect to copper on PCB (electrically this can be GND).

(open-drain output) will go low. Remove the fault by cycling

FLT

.

EN

= 475mA when USEL = high.

BAT

EN

APM8601

Document number: DS35138 Rev. 1 - 2

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December 2010

Functional Block Diagram

APM8601

DUAL CHANNEL SINGLE CELL LINEAR LITHIUM BATTERY

CHARGER WITH 28V OVP and PROGRAMMABLE CHARGE

TIMER

NEW PRODUCT

APM8601

Document number: DS35138 Rev. 1 - 2

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December 2010

APM8601

DUAL CHANNEL SINGLE CELL LINEAR LITHIUM BATTERY

CHARGER WITH 28V OVP and PROGRAMMABLE CHARGE

Absolute Maximum Ratings

Symbol Parameter Rating Unit

ESD Susceptibility (Note 2)

HBM Human Body Model 2 kV

MM Machine Model 200 V

Note: 2. Semiconductor devices are ESD sensitive and may be damaged by exposure to ESD events. Suitable ESD precautions should be

taken when handling and transporting this device.

Thermal Resistance (Note 3)

Symbol Parameter Rating Unit

θ

Junction to Ambient 40 °C/W

JA

Note: 3. Test condition for DFN3030-10: Device mounted on FR-4 2-layer board, 2oz copper, with minimum recommended pad on top layer and 6 vias to bottom layer 1.0”x1.5” ground plane.

NEW PRODUCT

DC, USB to GND -0.3 to 28V

,

BAT, CT, SETI, USEL, THM,

, EN to GND

POK

FLT

CHG

,

-0.3 to 6V

TIMER

V V

Recommended Operating Conditions (Note 4)

Symbol Parameter Rating Unit

Ambient Temperature Range

I

Typical Charge Current

CHARGE

Note: 4. The device function is not guaranteed outside of the recommended operating conditions.

Input Supply Voltage

-40 to +85

4.15 to 7.00

0.1 to 1.0

°C

V A

APM8601

Document number: DS35138 Rev. 1 - 2

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December 2010

APM8601

DUAL CHANNEL SINGLE CELL LINEAR LITHIUM BATTERY

CHARGER WITH 28V OVP and PROGRAMMABLE CHARGE

Electrical Characteristics

APM8601 is tested at VDC = V unless otherwise noted.

Symbol Parameter Test Conditions Min Typ. Max Unit VDC/V VDC/V

UVLO

USB USB

Input Voltage Range 0 28 V Input Operating Range (Note 5) 4.15 7.00 V Input Undervoltage Lock Out

(Note 5) OVLO Input Overvoltage Lock Out I

Input Supply Current I

DC/USB

I

Shutdown Current

SHTDWN

R

Input to BAT On-Resistance Input = 3.7V, V

DS_ON

V

DROPOUT

V

BAT

Input to BAT dropout Voltage

Battery Voltage Regulation I

BAT_REG

Battery Fast-Charge Restart

RSTTH

Threshold

NEW PRODUCT

I

DC_CHG

I

USB_CHG

SS Soft-Start Time Ramp time to fast-charge 1.2 ms

V

PREQ_TH

I

LEAK

R

SETI

Note: 5. Guaranteed by testing of undervoltage- and overvoltage-threshold. To completely charge a battery cell, the input voltage must be greater than 4.32V.

DC Charge Current

V

= 0V

USB

USB Charge Current

V

DC

= 0V

BAT Prequel Threshold

BAT Leakage Current

Resistance Range for SETI

= 5V, V

USB

= 4V, VEN = 0V, R

BAT

Input rising, 500mV hysteresis (typ.) V

Input rising, 200mV hysteresis (typ.)

BAT

EN

Input falling, 200mV hysteresis (typ.)

BAT

From BAT regulation voltage

R

SETI

R

SETI

R

SETI

Prequal, R V

BAT

V

USEL

V

USEL

Prequal, R V

BAT

V

BAT

hysteresis (typ.) V

DC

4.2V Guaranteed by charging

current

= 2kΩ, CCT = 68nF, at an ambient temperature of +25°C

SETI

BAT

= 3.2V

3.85 4.0 4.15 V

7.2 7.5 7.8 V

= 0mA, R

= High, TA = 25ºC

= 10kΩ 750 1200 µA

THM

275 435 µA

= 3.6V 0.5 0.8 Ω

BAT

5 55 150 mV

= 0mA, TA = 25ºC 4.179 4.2 4.221 V

-230 -175 -110 mV

= 1.5kΩ 950 1000 1140 = 2.0kΩ 727 750 870 = 5.0kΩ 280 300 353

= 2kΩ,

SETI

= 2.5V

60 75 95

= 5V 450 475 500 = 0V 75 90 105

= 2kΩ,

SETI

= 2.5V

rising, 180mV

= V

= 0V, V

USB

BAT

=

60 75 95

2.9 3.0 3.1 V

0.001 5 µA

1.5 5.0 kΩ

TIMER

mA

APM8601

Document number: DS35138 Rev. 1 - 2

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December 2010