DATASHEET

ISL9219
®
Data Sheet
April 7, 2010
FN6606.2
Li-ion Battery Charger
Features
The ISL9219 is a fully integrated high input voltage
single-cell Li-ion battery charger. This charger is fully in
compliance with the USB electrical specification. The
charger performs the CC/CV charge function required by
Li-ion batteries. The charger accepts an input voltage up to
28V but is disabled when the input voltage exceeds the OVP
threshold, typically 6V, to prevent excessive power
dissipation. The 28V rating eliminates the overvoltage
protection circuit required in a low input voltage charger.
• Complete Charger for Single-Cell Li-ion/Polymer Batteries
The fast charge current is programmable with an external
resistor, and the end-of-charge (EOC) current is fixed at
50mA for any input source type. When the input power
source is identified as a USB port, the host controller will
further identify the power type of the port and drive the USBI
pin accordingly.
• USB 100mA/500mA Comply
When the battery voltage is lower than the pre-charge
threshold, which is also programmable with an external
resistor, the charger preconditions the battery with an 85mA
constant current. Charge is complete when the charge current
reduces to the EOC current level during the CV charge phase.
The STAT1 and STAT2 provide unique indication for each
charging condition. An internal thermal foldback function
protects the charger from any thermal failure.
• Less than 1µA Leakage Current Off the Battery when No
Input Power Attached or Charger Disabled
• Low Component Count and Cost
• 0.7% Voltage Accuracy
• Programmable Charge Currents
• 250µA (Typ) Suspend Quiescent Current
• Charge Current Thermal Foldback for Thermal Protection
• Trickle Charge for Fully Discharged Batteries
• 28V Maximum Voltage for the Power Input
• Charge Status Indication
• Ambient Temperature Range: -40°C to +85°C
• Pb-free (RoHS Compliant)
Related Literature
• Technical Brief TB363 “Guidelines for Handling and
Processing Moisture Sensitive Surface Mount Devices
(SMDs)”
• Technical Brief TB379 “Thermal Characterization of
Packaged Semiconductor Devices”
• Technical Brief TB389 “PCB Land Pattern Design and
Surface Mount Guidelines for QFN Packages”
Pinout
20
19
18
17
16 VOUT
20 Ld 3x4 QFN L20.3x4
USBI
2
15 TS
*Add “-T” suffix for tape and reel. Please refer to TB347 for details on
reel specifications.
AC_IN
3
14 PG
NOTE: These Intersil Pb-free plastic packaged products employ
special Pb-free material sets, molding compounds/die attach
materials, and 100% matte tin plate plus anneal (e3 termination finish,
which is RoHS compliant and compatible with both SnPb and Pb-free
soldering operations). Intersil Pb-free products are MSL classified at
Pb-free peak reflow temperatures that meet or exceed the Pb-free
requirements of IPC/JEDEC J STD-020.
TRKL
4
13 NC
STAT1
5
12 TIMER
STAT2
6
11 GND
219
-40 to +85
1
7
8
9
10
EN
1
ACFLT
VIN
PACKAGE
ISET
PKG.
DWG. #
ISL9219IRZ*
PART
TEMP.
MARKING RANGE (°C)
PRECH
PART
NUMBER
VOUT
Ordering Information
NC
ISL9219
(20 LD 3X4 QFN)
TOP VIEW
NC
Additional features include an OVP protected power-good
source, preconditioning of an over-discharged battery, an
NTC thermistor interface for charging the battery in a safe
temperature range, automatic recharge, and thermally
enhanced QFN package.
• No External Blocking Diode Required
VIN
The STAT1, STAT2, TRKL and ACFLT pins are of open drain
type, allowing a simple interface to a microprocessor or an
LED. When no adapter is attached or when disabled, the
charger draws less than 1µA leakage current from the
battery.
• Integrated Pass Element and Current Sensor
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774 | Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2008, 2010. All Rights Reserved
All other trademarks mentioned are the property of their respective owners.
ISL9219
Absolute Maximum Ratings
Thermal Information
Supply Voltage (VIN) . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 30V
Output Pin Voltage (STAT1, STAT2, PG, ACFLT) . . . . . . -0.3V to 7V
All Other Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 5.5V
Maximum Output Current. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1.5A
Thermal Resistance (Junction to Ambient) θJA (°C/W) θJC (°C/W)
3x4 QFN Package (Notes 1, 2) . . . .
41
4.5
Maximum Junction Temperature (Plastic Package) . . . . . . . +150°C
Maximum Storage Temperature Range . . . . . . . . . .-65°C to +150°C
Pb-free Reflow Profile . . . . . . . . . . . . . . . . . . . . . . . . .see link below
http://www.intersil.com/pbfree/Pb-FreeReflow.asp
Recommended Operating Conditions
Ambient Temperature Range . . . . . . . . . . . . . . . . . . .-40°C to +85°C
Maximum Supply Voltage, VIN . . . . . . . . . . . . . . . . . . . . . . . . . .28V
Supply Voltage, VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4.3V to 6V
Programmable Charge Current . . . . . . . . . . . . . . . . . . . 50mA to 1A
CAUTION: Do not operate at or near the maximum ratings listed for extended periods of time. Exposure to such conditions may adversely impact product reliability and
result in failures not covered by warranty.
NOTES:
1. θJA is measured in free air with the component mounted on a high effective thermal conductivity test board with “direct attach” features. See
Tech Brief TB379.
2. θJC, “case temperature” location is at the center of the exposed metal pad on the package underside. See Tech Brief TB379.
Electrical Specifications
Typical values are tested at VIN = 5V and +25°C Ambient Temperature, maximum and minimum values are
established over the Recommended Operating Conditions, unless otherwise noted.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNITS
POWER-ON RESET
Rising VIN Threshold
VPOR
3.4
3.6
3.8
V
Falling VIN Threshold
VPOR
2.2
2.4
2.6
V
Rising Edge
VOS
-
90
150
mV
Falling Edge
VOS
10
50
-
mV
VACFLT
4.3
4.4
4.5
V
VIN < V POR or EN = HI
-
1
5.0
µA
VIN-BAT OFFSET VOLTAGE
AC FAULT DETECTION THRESHOLD
AC Fault Threshold
STANDBY CURRENT
VOUT Pin Sink Current
ILEAK
VIN Pin Supply Current
ISTANDBY
VOUT floating and EN = HI
-
250
300
µA
VIN Pin Supply Current
IRUN
VOUT floating and EN = LO
-
1
2
mA
Output Voltage
VCH
TA = +25°C, IOUT = 0mA
4.185
4.20
4.215
V
Output Voltage
VCH
IOUT = 0mA
4.169
4.20
4.231
V
-
300
430
mV
VOLTAGE REGULATION
VOUT = 4.2V, IOUT = 1A
Dropout Voltage
OVERVOLTAGE PROTECTION
Overvoltage Protection Rising Threshold
VOVPR
5.64
6.0
6.36
V
Overvoltage Protection Falling Threshold
VOVPF
5.54
5.6
-
V
0.9
1.0
1.1
A
2.364
2.4
2.436
V
OUTPUT CURRENT
Constant Charge Current
ICHARGE
Output Current Set Voltage
AC input RISET = 24kΩ
VISET
Constant Charge Current
ICHARGE
USBI = HI
380
430
490
mA
Constant Charge Current
ICHARGE
USBI = LO or floating
65
85
95
mA
Trickle Charge Current
ITRICKLE
For any input type
65
85
95
mA
2
FN6606.2
April 7, 2010
ISL9219
Electrical Specifications
Typical values are tested at VIN = 5V and +25°C Ambient Temperature, maximum and minimum values are
established over the Recommended Operating Conditions, unless otherwise noted. (Continued)
PARAMETER
SYMBOL
End-of-Charge Threshold
IMIN
TEST CONDITIONS
For any input type
MIN
TYP
MAX
UNITS
30
50
70
mA
4.05
4.1
4.15
V
RECHARGE THRESHOLD
Recharge Voltage Threshold
VRECH
TRICKLE CHARGE THRESHOLD
Trickle Charge Threshold Voltage
VMIN
PRECH is floating
2.9
3.0
3.1
V
Trickle Charge Threshold Voltage
VMIN
RPRECH = 82.5k
2.375
2.475
2.575
V
VMIN_HYS
35
60
150
mV
ITS
4.8
5.0
5.3
µA
Low Battery Temperature Threshold
VTMIN
1.86
1.88
1.91
V
High Battery Temperature Threshold
VTMAX
0.145
0.16
0.175
V
Battery Removal Threshold
VRMV
-
2.25
-
V
Charge Current Foldback Threshold
TFOLD
-
125
-
°C
Current Foldback Gain
GFOLD
-
100
-
mA/°C
2.5
3.0
3.3
ms
40
100
170
ms
Input High (USBI, EN, AC_IN)
1.4
-
-
V
Input Low (USBI, EN, AC_IN)
-
-
0.4
V
-
-
1
µA
20
-
-
mA
rDS(ON)
-
3
5
Ω
IPG
-
60
-
mA
Trickle Charge Threshold Hysteresis
TEMPERATURE MONITORING
Constant Current Source For TS
OSCILLATOR
Oscillation Period
tOSC
CTIME = 15nF
DE-GLITCH TIME
De-Glitch Time For EOC, Recharge
tDEG
LOGIC INPUT AND OUTPUT
Open Drain Leakage Current When HI
(STAT1, STAT2, ACFLT, TRKL)
Pin Voltage = 6V
Open Drain Sink Current When LOW
(STAT1, STAT2, ACFLT, TRKL)
Pin Voltage = 0.3V
VIN to PG Switch
PMOSFET ON-Resistance
Maximum Output Current
3
FN6606.2
April 7, 2010
ISL9219
Pin Descriptions
ISET (Pin 8)
VIN (Pins 1, 20)
Input supply voltage, Connect a 1µF ceramic capacitor to
power ground.
Charge-current programing and monitoring pin. Connect a
resistor between this pin and the GND pin to set the charge
current limit by Equation 2:
24000
I OUT = ----------------R ISET
USBI (Pin 2)
USB power type selection logic input. When this pin is left
floating or driven to logic LOW, the USB port is regarded as
a low-power port with 100mA maximum output current. In
such cases, the charge current is internally set to 85mA.
When this pin is driven to logic HIGH, the USB port is
considered a high-power port with a 500mA maximum
current available. In such cases, the charge current is set at
430mA regardless of the ISET resistor. There is a 600k
pull-down resistor between the USBI pin to GND.
( mA )
(EQ. 2)
Where RISET is in kΩ.
The ISET pin voltage also monitors the actual charge current
during the entire charge cycle, including the trickle, constantcurrent, and constant-voltage phases. However, when the
dropout voltage is reached, the ISET pin voltage will no
longer follow the output current due to fact that the output
current is no longer controlled by the IC. When disabled,
VISET = 0V
AC_IN (Pin 3)
ACFLT (Pin 9)
Input source type configuration pin. Pull this pin to logic HI to
configure the charger for an AC adapter. If this pin is left
floating or driven to logic LO, the charger is configured for
USB source type, where the charge current is set at 430mA
or 85mA, depending on the USBI status. There is a 600k
pull-down resistor between the AC_IN pin to GND.
Open-drain indication pin which turns off when the adapter
plugged in does not have sufficient current rating and
the resulting input voltage is dropped to below 4.4V.
TRKL (Pin 4)
EN (Pin 10)
Open-drain indication pin which turns on when charger is in
trickle mode, otherwise turns off. This pin is capable to sink
20mA minimum current to drive an LED.
IC enable input. Drive this pin to logic LO or leave it floating
to enable the charger. Drive this pin to logic HI to disable the
charger. There is a 600k pull-down resistor between the EN
pin to GND.
STAT1 (Pin 5)
Open-drain indication pin. In conjunction with STAT2 this pin
provides a unique indication for each charging state of the
cycle. This pin is capable to sink 20mA minimum current to
drive an LED.
STAT2 (Pin 6)
Open-drain indication pin. In conjunction with STAT1 this pin
provides a unique indication for each charging state of the
cycle. This pin is capable to sink 20mA minimum current to
drive an LED.
PRECH (Pin 7)
PG (Pin 14)
The PG pin will be connected to VIN through an internal
P-Channel MOSFET when VIN is within the power good
window. Otherwise the PG pin is in a high impedance
(floating) state. When VIN is within the power good window,
the PG pin can source 20mA output current for the down
stream circuit. It is recommended that a 2.2µF ceramic
capacitor be connected at the PG pin to absorb any transient
voltage due to the delay turning off the PMOS under a fast
OVP condition.
TS (Pin 15)
Pre-charge threshold voltage programming input pin.
Connect a resistor between this pin and GND to set the
threshold voltage by Equation 1:
3 × R PRECH
V PRECH = ---------------------------------100
This pin is capable to sink 20mA minimum current to drive an
LED. The open drain indication also turns off when an input
OVP condition (VIN > 6V) is encountered.
(V)
(EQ. 1)
Input for an external NTC thermistor for temperature
monitoring. A 5µA internal current source is provided at this
pin and the pin voltage is monitored and compared with the
set thresholds to provide over temperature protection.
TIMER (Pin 12)
Where RPRECH is in kΩ, valid for RPRECH ≤ 100kΩ.
4
The TIMER pin sets the oscillation period by connecting a
timing capacitor between this pin and GND. The oscillator
also provides a time reference for the charger. The timer
function can be disabled by connecting the TIMER pin to
GND. If the timer is disabled, there will be no timeout
function for any operation mode including trickle charge and
fast charge modes.
FN6606.2
April 7, 2010
ISL9219
VOUT (Pins 16, 17)
EPAD
Charger output pin. Connect this pin to the battery. A 1µF or
larger X5R ceramic capacitor is recommended for
decoupling and stability purposes.
Exposed pad. Connect to GND electrically. Thermally,
connect as much as possible copper to this pad either on the
component layer or other layers through thermal vias to
enhance the thermal performance.
GND (Pin 11)
System ground connection
NC (Pins 13, 18, 19)
No connect
Typical Application
TO INPUT SOURCE
TO BATT
VOUT
VIN
C1
R1
R2
R3
R4
D1
D2
D3
R5
C2
*
USBI
D4
ACFLT
STAT1
STAT2
TRKL
AC_IN
R6
R7
PG
GND
CT
TO DOWN STREAM
CIRCUIT
TS
TIMER
ISET
AC/USB
EN
PRECG
AC
ISL9219
DIS
EN
500mA
100mA
RT
* SEE INPUT AND OUTPUT CAPACITOR SELECTION
5
FN6606.2
April 7, 2010
ISL9219
Block Diagram
QMAIN
VIN
VOUT
VOUT
C1
REFERENCES
TEMPERATURE
MONITORING
VRECHRG
VCH
VPOR
100000:1
CURRENT
MIRROR
VMIN
QSEN
IT
ISEN
INPUT_OK
+
-
RISET
IR
+
VPOR
-
+
CA
-
ISET
VIN
80mV
CURRENT
REFERENCES
+
CHRG
+
IMIN = 20mA
VA
VCH
+
TRICKLE/FAST
MINBAT
VMIN
ISEN
+
R1
VRECHRG
-
+
MIN_I
PRECH
-
R2
RPRECH
RECHARGE
STAT1
VIN
USBI
EN
STAT2
LOGIC
5µA
TS
VIN
TIMER
OSC
COUNTER
GND
PG
AC_IN
ACFLT
TRKL
6
FN6606.2
April 7, 2010
ISL9219
Theory of Operation
The ISL9219 is an integrated charger for single-cell Li-ion or
Li-polymer batteries. The ISL9219 functions as a traditional
linear charger when powered with a voltage-source adapter.
When powered with a current-limited adapter, the chargers
minimizes the thermal dissipation commonly seen in
traditional linear chargers.
As a linear charger, the ISL9219 charges a battery in the
popular constant current (CC) and constant voltage (CV)
profile. The constant charge current ISET is programmable
up to 1A with an external resistor. The charge voltage VCH
has 0.7% accuracy over the entire recommended operating
condition range. The charger always preconditions the
battery with a 85mA constant current at the beginning of a
charge cycle, until the battery voltage is verified to be above
the minimum fast charge voltage, VMIN. This low-current
preconditioning charge mode is named trickle mode. A
thermal-foldback feature removes the thermal concern
typically seen in linear chargers. The charger reduces the
charge current automatically as the IC internal temperature
rises above +125°C to prevent further temperature rise. The
thermal foldback feature guarantees safe operation when
the printed circuit board (PCB) is space limited for adequate
thermal dissipation.
USB Compliant Current Setting
The ISL9219 is fully compliant with the USB electrical
specification when a USB port is used as the input source.
The input source type can be identified by the host controller.
When the USB connector is plugged in, the host controller
will identify the device during the enumeration process. The
host controller will further identify whether the USB port is a
high power port (500mA max current) or low power port
(100mA max current). The host controller will then drive the
AC_IN and USBI pins thru its GPIO pins, according to the
identification results.
If USB compliance is not required, the AC_IN pin can be
hard wired to VOUT so that the fast charge current is always
set by ISET pin.
Depending on the input source type, the charge current
during the constant current phase is:
ISET: determined by RISET if input is an AC adapter
ISET = 430mA if input is a high power USB port
ISET = 85mA if input is a low power port
Power-Good Range
The power-good range is defined by the following three
conditions:
1. VIN > VOVP
where the VOS is the offset voltage for the input and output
voltage comparator and the VOVP is the overvoltage
protection threshold given in the “Electrical Specification”
table on page 2. All VPOR, VOS, and VOVP have hysteresis,
as given in the Electrical Specification table. If the input
voltage is not in the power-good range, the charger will not
charge the battery. If the input voltage is within the power
good range, the PG pin will be connected to VIN through an
internal P-Channel MOSFET with a 20mA current capability.
If the input voltage is not within the power-good range, the
PG will be switched off from VIN and turned into a high
impedance (floating) state. When an overvoltage condition
occurs, the ISL9219 enters the suspended state.
Timeout Function
The charger offers a safety timer for setting the maximum
charge time (TIMEOUT) limit to prevent charging a dead
battery for an extensively long time. The trickle mode is
limited to 1/8 of TIMEOUT limit. The charger automatically
re-charges the battery when the battery voltage drops below
a recharge threshold.
State Indication
Five indication pins, STAT1, STAT2, ACFLT, PG and TRKL
are available from the charger to indicate the charge status
and fault conditions. The STAT1 and STAT2 are configured
to indicate various charging condition as given by the true
table in Table 1:
TABLE 1. STAT1 AND STAT2 TRUE TABLE
STAT1
STAT2
CHARGING CONDITION
L
L
Charging
L
H
Charge Complete and during Re-Charge
H
L
Fault
H
H
Suspend
A fault status is triggered under one of these conditions:
1. The TS pin voltage is outside the preset temperature
window
2. Timeout occurs before the EOC current has been
reached
The ACFLT pin indicates a faulty AC adapter condition. It is
an open drain output which turns off when there is an AC
fault, otherwise stays on. An AC fault condition is defined as
when VIN falls below VACFLT threshold (4.4V) or VIN goes
above VOVP (6.0V).
The TRKL pin indicates that the operation is in trickle charge
mode. It is an open drain output which turns on when the
operation is in trickle mode, otherwise turns off.
The PG pin indicates that VIN is within the power-good
range.
2. VIN - VBAT > VOS
3. VIN < VOVP
7
FN6606.2
April 7, 2010
ISL9219
Applications Information
Power on Reset (POR)
The ISL9219 resets as the input voltage rises above the
POR rising threshold. The internal oscillator starts to
oscillate, the internal timer is reset, and the charger begins
to charge the battery. The STAT pins, will indicate the
operating condition according to Table 1.
The ISL9219 has a typical rising POR threshold of 3.6V and
a falling POR threshold of 2.4V.
Pre-Charge
If the battery voltage is below the pre-charge threshold, the
ISL9219 charger delivers a small current to pre-charge the
battery until the voltage reaches the fast charge threshold
value. The pre-charge threshold is programmed by the
resistor connected between the PRECH pin and GND. If the
PRECH pin is left floating, a default value of 3.0V is used as
the pre-charge voltage.
Charge Cycle
A charge cycle consists of three charge modes: trickle mode,
constant current (CC) mode, and constant voltage (CV)
mode. The charge cycle always starts with the trickle mode
until the battery voltage stays above VMIN (3.0V typical). If
the battery voltage stays below VMIN, the charger stays in
the trickle mode. The charger moves to the CC mode after
the battery voltage is above VMIN. As the battery-pack
terminal voltage rises to the final charge voltage (VCH), the
CV mode begins. Since the battery terminal voltage is
regulated at the constant VCH in the CV mode, the charge
current is expected to decline as the cell voltage rises. After
the charge current drops below IMIN, which is fixed at 50mA
for any input type, the ISL9219 indicates the end-of-charge
(EOC) with STAT1 and STAT2. The charging actually does
not terminate until the internal timer completes its length of
TIMEOUT in order to bring the battery to its full capacity.
page 5. The oscillator charges the timing capacitor to 1.5V
and then discharges it to 0.5V in one period, both with 10µA
current. The period tOSC is shown in Equation 3:
6
t OSC = 0.2 ⋅ 10 ⋅ C TIME
( sec onds )
(EQ. 3)
A 1nF capacitor results in a 0.2ms oscillation period. The
accuracy of the period is mainly dependent on the accuracy
of the capacitance and the internal current source.
Total Charge Time
The total charge time for the CC mode and CV mode is
limited to a length of TIMEOUT. A 22-stage binary counter
increments each oscillation period of the internal oscillator to
set the TIMEOUT. The TIMEOUT can be calculated as
Equation 4:
TIMEOUT = 2
22
C TIME
⋅ t OSC = 14 ⋅ -----------------1nF
( minutes )
(EQ. 4)
A 1nF capacitor leads to 14 minutes of TIMEOUT. For
example, a 15nF capacitor sets the TIMEOUT to be
3.5 hours. The charger has to reach the end-of-charge
condition before the TIMEOUT, otherwise, a TIMEOUT fault
is issued. The TIMEOUT fault latches up the charger. There
are two ways to release such a latch-up: either to recycle the
input power, or toggle the EN pin to disable the charger and
then re-enable it.
The trickle mode charge has a time limit of 1/8 TIMEOUT. If
the battery voltage does not reach VMIN within this limit, a
TIMEOUT fault is issued and the charger latches up. Thus,
the charger can stay in trickle mode for no more than 1/8 of
TIMEOUT interval.
Monitoring Output Current thru ISET Pin
• The EN pin is toggled from HI to LO or from HI to floating
In addition to programming the fast charge current, the ISET
can be used to monitor the actual output current for the AC
adapter input current setting. During the constant current
phase, the ISET pin voltage is fixed at 2.4V. In this case, the
output current can be calculated by using 2.4V divided by
RISET. During the constant voltage phase, the output current
can be calculated by using the pin voltage, divided by RISET.
For USB input current setting, VISET can still be used to
monitor the charge current but since VISET is not used for
the close loop current regulation, to achieve a good
accuracy, an one-point calibration is required.
Recharge
End-of-Charge (EOC) Current
After a charge cycle completes at a timeout event, charging
is prohibited until the recharge condition (VOUT < VRECH)
is met. Then the charging restarts with the timer reset to
zero. The STAT1 and STAT2 indication however, is
unchanged.
The end-of-charge current IMIN sets the level at which the
charger starts to indicate the charge complete condition with
the indication pins. The charger actually does not terminate
charging until the end of the TIMEOUT interval, as described
in “Total Charge Time” on page 8. The IMIN is fixed at 50mA
for all input types, i.e. for AC adapter, USB high power and
USB low power.
The following events initiate a new charge cycle:
• POR
• A new battery being inserted (detected by TS pin)
• Recovery from an battery over-temperature fault
Internal Oscillator
The internal oscillator establishes a timing reference. The
oscillation period is programmable with an external timing
capacitor, CTIME, as shown in “Typical Application” on
8
FN6606.2
April 7, 2010
ISL9219
Charge Current Thermal Foldback
Overheating is always a major concern in a linear charger.
The maximum power dissipation usually occurs at the
beginning of a charge cycle when the battery voltage is at its
minimum but the charge current is at its maximum. The
charge current thermal foldback function in the ISL9219
eliminates the overheating problem.
The thermal foldback function has no impact on the charge
current until the internal temperature reaches approximately
+125°C; then charge current is reduced at a rate of
100mA/°C. For a charger with the constant charge current
set at 1A, the charge current is reduced to zero when the
internal temperature rises to +135°C.
OVP Protection
The ISL9219 is capable for up to 28V at the input pin.
However, reliability reason, the charger will stop charging
should the input voltage exceed 6V. This feature prevents
excessive heating generated by the high input voltages. If an
OVP condition is encountered, the PG pin will turn to high
impedance to indicate the OVP condition, the changer
enters the suspend state and the ACFLT turns to high
impedance. If VIN is within the power good range, the PG
pin is connected to VIN pin internally to provide a 20mA
supply current to the down stream circuit.
VTMIN (1.88V)
VTMIN- (1.68V)
TS PIN
VOLTAGE
VTMAX+ (0.18V)
VTMAX (0.16V)
0V
UNDER
TEMP
OVER
TEMP
FIGURE 1. THRESHOLD VOLTAGES FOR 0°C to +50°C
WINDOW
2.8V
TS FUNCTION
5μA
R1
BATTERY
REMOVAL
VRMV
CP1
-
UNDER
TEMP
TS
R2
+
VTMIN
CP2
R3
+
TO TS PIN
Q1
RT
OVER
TEMP
NTC Thermistor
The ISL9219 provides a TS pin to monitor the battery
temperature to ensure a safe charging temperature range.
The temperature range is programmable with an external
negative temperature coefficient (NTC) thermistor. The
TEMP pin is also used to detect the removal of the battery.
The ISL9219 uses two comparators (CP2 and CP3) to form a
window comparator, as shown in Figure 2. When the TS pin
voltage is “out of the window,” determined by the VTMIN and
VTMAX, the ISL9219 stops charging and indicates a fault
condition. When the temperature returns to the set range, the
charger re-starts a charge cycle. The two MOSFETs, Q1 and
Q2, produce hysteresis for both upper and lower thresholds.
The temperature window is shown in Figure 1 for a 0°C to
+50°C typical application using a Mitsubishi type
TH11-4H104F thermistor.
CP3
R4
VTMAX
+
Q2
R5
GND
FIGURE 2. INTERNAL CIRCUIT FOR NTC INTERFACE
Battery Removal Detection
The ISL9219 assumes that the thermistor is co-packed with
the battery and is removed together with the battery. When
the charger senses a TS pin voltage that is 2.25V or higher,
it assumes that the battery is removed. The battery removal
detection circuit is also shown in Figure 2. When a battery is
removed, the ISL9219 enters the suspend state and the
charging is halted. When a battery is inserted again, a new
charge cycle starts.
Shutdown and Suspend State
The ISL9219 can be orderly shutdown by one of these
conditions:
1. EN pin is pulled to logic HI
2. The battery has been removed from the charger. The
battery removal condition can be detected by the TS pin
(see “Battery Removal Detection” on page 9).
When shut down, the charger stays in the suspend state and
draws typically less than 300µA current from the input
power.
Under an OVP condition, the charger also enters the
suspend state.
9
FN6606.2
April 7, 2010
ISL9219
Input and Output Capacitor Selection
A 0.47µF or higher value ceramic capacitor for the input is
recommended. Due to the inductance of the power leads of
the wall adapter or USB source, the input capacitor type
must be properly selected to prevent high voltage transient
during a hot-plug event. A tantalum capacitor is a good
choice for its high ESR, providing damping to the voltage
transient. Multi-layer ceramic capacitors, however, have a
very low ESR and hence when chosen as input capacitors, a
1Ω series resistor is recommended, as shown in the “Typical
Application” schematic on page 5, to provide adequate
damping.
When the battery is attached to the charger, the output
capacitor can be any ceramic type with the value higher than
0.1µF. However, if there is a chance the charger will be used
as an LDO linear regulator, a 10µF tantalum capacitor is
recommended.
Board Layout Recommendations
The ISL9219 internal thermal foldback function limits the
charge current when the internal temperature reaches
approximately +125°C. In order to maximize the current
capability, it is very important that the exposed pad under the
package is properly soldered to the board and is connected
to other layers through thermal vias. More thermal vias and
more copper attached to the exposed pad usually result in
better thermal performance. On the other hand, the number
of vias is limited by the size of the pad. The exposed pad is
big enough for 5 vias.
State Diagram
The state diagram is shown in Figure 3. There area total of
5 states during a complete charging cycle: trickle charge, CC
charge, CV charge, charge complete/recharge, fault and
suspend. In the trickle mode, the ISL9219 charges the
battery in a trickle current. If VOUT reaches VMIN before the
trickle charge timeout interval, the operation will move to the
CC mode. Before entering the CC mode, the input source is
identified. The CC mode output current is set according to
the input type as described in “USB Compliant Current
Setting” on page 7. When the output voltage reaches the
4.2V final voltage, the operation will move CV mode, where
the battery is charged at a constant voltage. If the end-ofcharge current is reached before the timeout interval is
elapsed, the operation moves to charge complete state. The
charger continues to charge the battery until a timeout
condition is reached, then the charging will be terminated.
After the termination, if the output voltage drops below the
recharge threshold, a recharge starts and the timer is rest to
zero. The STAT1 and STAT2 indications, remains the same
as the charge complete state.
In the event that the timeout condition is reached before
EOC, the fault mode is entered. The fault mode can also be
triggered by an OTP event. To exit the fault mode, the input
power has to be removed and re-applied, or the EN pin is
toggled to HI and back to LO, then a new cycle starts.
All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems.
Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without
notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
10
FN6606.2
April 7, 2010
ISL9219
POWER
UP
VIN>VPOR?
N
Y
N
VIN<VOVP?
ACFLT = H
Y
Y
POR
AC_IN = HI?
N
N
VIN>VOUT +VOS?
Y
SUSPEND
STAT1 = H
STAT2 = H
N
EN = LO ?
ANYTIME
WHEN
BATT IS
REMOVED
Y
Y
INITIALIZATION
RESET
COUNTER
IOUT = 500mA
IOUT = ISET
TRICKLE CHARGE
STAT1 = L
STAT2 = L
PG = VIN
ACFLT = L
IOUT = 100mA
Y
VOUT>V MIN
CV CHARGE
STAT1= L
STAT2 = L
PG = VIN
ACFLT = L
IOUT < IMIN ?
CV CHARGE
STAT1= L
STAT2 = L
PG = VIN
ACFLT = L
ANYTIME WHEN
VIN < 4.4V
ACFLT = H
N
N
USBI = HI?
EN = H
Y
N
CHARGE
COMPLETE
STAT1 = L
STAT2 = H
PG = VIN
ACFLT = L
TIMEOUT?
N
Y
VOUT =
4.2V?
N
TRICKLE
TIMEOUT ?
N
Y
Y
N
TIMEOUT ?
Y
OTP
FAULT
STAT1 = H
STAT2 = L
POR OR
EN TOGGLED
TIMEOUT ?
N
Y
CHARGE COMPLETE
STAT1 = L
STAT2 = H
CHARGER OFF
VOUT <
VRECH?
N
Y
POR
RE-CHARGE
STAT1 = L
STAT2 = H
CHARGER ON
TIMER RESET
TIMEOUT ?
Y
N
FIGURE 3. STATE DIAGRAM
11
FN6606.2
April 7, 2010
ISL9219
Package Outline Drawing
L20.3x4
20 LEAD QUAD FLAT NO-LEAD PLASTIC PACKAGE
Rev 1, 3/10
3.00
0.10 M C A B
0.05 M C
A
B
4
20X 0.25
16X 0.50
+0.05
-0.07
17
A
16
6
PIN 1
INDEX AREA
6
PIN 1 INDEX AREA
(C 0.40)
20
1
4.00
2.65
11
+0.10
-0.15
6
0.15 (4X)
A
10
7
VIEW "A-A"
1.65
TOP VIEW
+0.10
-0.15
20x 0.40±0.10
BOTTOM VIEW
SEE DETAIL "X"
0.10 C
C
0.9± 0.10
SEATING PLANE
0.08 C
SIDE VIEW
(16 x 0.50)
(2.65)
(3.80)
(20 x 0.25)
C
(20 x 0.60)
0.2 REF
5
0.00 MIN.
0.05 MAX.
(1.65)
(2.80)
DETAIL "X"
TYPICAL RECOMMENDED LAND PATTERN
NOTES:
1. Dimensions are in millimeters.
Dimensions in ( ) for Reference Only.
2. Dimensioning and tolerancing conform to AMSE Y14.5m-1994.
3. Unless otherwise specified, tolerance : Decimal ± 0.05
4. Dimension applies to the metallized terminal and is measured
between 0.15mm and 0.30mm from the terminal tip.
5. Tiebar shown (if present) is a non-functional feature.
6. The configuration of the pin #1 identifier is optional, but must be
located within the zone indicated. The pin #1 indentifier may be
either a mold or mark feature.
12
FN6606.2
April 7, 2010
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