Intersil ISL9301IRZ High input voltage charger with power path management Datasheet

ISL9301
Data Sheet
September 21, 2011
High Input Voltage Charger With Power
Path Management
The ISL9301 is a fully integrated high input voltage
single-cell Li-ion battery charger with power path
management function. This 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 10.5V OVP threshold. The 28V rating
eliminates the overvoltage protection circuit required in a
low-voltage charger. The charge current and the
end-of-charge (EOC) current are programmable with
external resistors. When the battery voltage is lower than
2.8V, the charger preconditions the battery with 16% of the
programmed charge current. When the charge current
reduces to the programmable EOC current level during the
CV charge phase, the EOC indicator (CHG) will toggle to
logic HIGH to indicate the end-of-charge condition. The
charger will continue to charge until the user programmed
timeout interval has elapsed, then the charger is terminated.
The ISL9301 uses separate power paths to supply the
system load and charge the battery. This feature allows the
system to immediately operate with a completely discharged
battery. This feature also allows the charge to terminate
when the battery is full while continuing to supply the system
with the input source, thus minimizing unnecessary
charge/discharge cycles and improving the battery life.
Two indication pins (PPR and CHG) allow simple interface to
a microprocessor or LEDs.
Ordering Information
PART
NUMBER
PART
(Notes 1, 2, 3) MARKING
ISL9301IRZ
TEMP.
RANGE
(°C)
FN6435.3
Features
• Complete Charger for Single-Cell Li-ion/Polymer Batteries
• Power Path Management Optimize Charge and System
Currents
• Intelligent Timeout Interval Based on Actual Charge
Current
• Integrated Disconnect Switch to Disconnect the Battery
• 1% Charger Output Voltage Accuracy
• Programmable Charge Current
• Programmable End-of-Charge Current
• Charge Current Thermal Foldback for Thermal Protection
• Trickle Charge for Fully Discharged Batteries
• 28V Maximum Voltage at VIN pin
• Power Presence and Charge Indications
• Ambient Temperature Range: -40°C to +85°C
• 10 Ld 3x3 DFN Package
• Pb-Free (RoHS Compliant)
Applications
• Mobile Phones
• Blue-Tooth Devices
• PDAs
• MP3 Players
• Stand-Alone Chargers
PACKAGE
(Pb-Free)
PKG.
DWG. #
9301
-40 to +85 10 Ld 3x3 DFN L10.3x3C
ISL9301IRZ-T 9301
-40 to +85 10 Ld 3x3 DFN L10.3x3C
• Other Handheld Devices
Pinout
ISL9301
(10 LD DFN)
TOP VIEW
NOTES:
1. Please refer to TB347 for details on reel specifications.
2. 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.
VIN
1
10 VOUT
VBAT
2
9
BATON
PPR
3
8
IREF
CHG
4
7
IMIN
TIME
5
6
GND
3. For Moisture Sensitivity Level (MSL), please see device
information page for ISL9301. For more information on MSL,
please see Technical Brief TB363.
1
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.
ISL9301
Absolute Maximum Ratings (Reference to GND)
Thermal Information
VIN . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 30V
All other pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to 7V
Thermal Resistance (Typical)
θJA (°C/W)
θJC (°C/W)
DFN Package (Notes 4, 5) . . . . . . . . . .
40.5
2.5
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 Pin). . . . . . . . . . . . . . . . . . . . . . 28V
Operating Supply Voltage (VIN Pin). . . . . . . . . . . . . . . . 4.3V to 10V
Programmed Charge Current . . . . . . . . . . . . . . . . . 50mA to 450mA
Output Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0mA to 800mA
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:
4. 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.
5. For θJC, the “case temp” location is the center of the exposed metal pad on the package underside.
Electrical Specifications
Typical values are tested at VIN = 5V and the ambient temperature at +25°C. Range. VSUPPLY = ±5V, AV = +1,
RL = 100Ω; Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified.
Temperature limits established by characterization and are not production tested.
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNITS
3.3
3.9
4.3
V
3.1
3.6
4.15
V
-
110
250
mV
10
100
-
mV
10
10.5
13
V
200
400
500
mV
Charger disabled or the input is floating
-
-
1.0
µA
No supply at VIN, BATON = HI
-
10
-
µA
Charger enabled
-
1
-
mA
4.40
4.50
4.60
V
4.22
4.35
4.45
V
POWER-ON RESET
Rising POR Threshold
VPOR
Falling POR Threshold
VPOR
VBAT = 3.0V, use PPR to indicate the comparator
output.
VOUT-BAT OFFSET VOLTAGE
Rising Edge
VOS
Falling Edge
VOS
VBAT = 4.0V, use CHG pin to indicate the comparator
output (Note 6)
VIN OVERVOLTAGE PROTECTION
Overvoltage Protection Threshold
VOVP
OVP Threshold Hysteresis
Use PPR to indicate the comparator output
STANDBY CURRENT
BAT Pin Sink Current
ISTANDBY
BAT Pin Supply Current
IVBAT
VIN Pin Supply Current
IVIN
VOLTAGE REGULATION
Output Voltage
VOUT
Output PPM Threshold Voltage
System current + charge current = 15mA
VDPPM
Charger Output Voltage
VBAT
Charge current = 10mA
4.158
4.20
4.242
V
IREF PIN Voltage
VIREF
VBAT = 3.8V
1.165
1.20
1.245
V
MOSFET ON-RESISTANCE
Regulator MOSFET rDS(ON)
rDS(ON)
VOUT = 4.4V, Total current = 0.3A
-
0.8
1.2
Ω
Charger MOSFET rDS(ON)
rDS(ON)
VBAT = 3.8V, charge current = 0.2A
-
0.1
0.15
Ω
VRECHG
Relative to VBAT
-200
-150
-100
mV
RECHARGE THRESHOLD
Recharge Voltage Threshold
CURRENT REGULATION (Note 7)
Input Current Limit
ILIM
VOUT = 4.5V
600
800
1200
mA
Constant Charge Current
ICHG
RIREF = 26.7kΩ, VBAT = 2.8V to 4.0V
130
145
160
mA
2
FN6435.3
September 21, 2011
ISL9301
Electrical Specifications
Typical values are tested at VIN = 5V and the ambient temperature at +25°C. Range. VSUPPLY = ±5V, AV = +1,
RL = 100Ω; Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified.
Temperature limits established by characterization and are not production tested. (Continued)
PARAMETER
SYMBOL
TEST CONDITIONS
MIN
TYP
MAX
UNITS
Trickle Charge Current
ITRK
RIREF = 26.7kΩ, VBAT = 2.4V
17
23
30
mA
End-of-Charge Current
IMIN
RIMIN = 137kΩ
18
23
28
mA
PRECONDITIONING CHARGE THRESHOLD
Preconditioning Charge Threshold
Voltage
VMIN
2.7
2.8
3.0
V
Preconditioning Voltage Hysteresis
VMINHYS
40
100
150
mV
-
115
-
°C
INTERNAL TEMPERATURE MONITORING (Note 8)
Charger Current Thermal Foldback
Threshold
TFOLD
OVER-TEMPERATURE PROTECTION (Note 8)
Shutdown Rising Threshold
TR
-
142
-
°C
Shutdown Falling Threshold
TF
-
110
-
°C
RTIME = 1MΩ
60
75
90
µs
BATON Pin Logic Input High
VBAT < 4.5V
1.1
-
-
V
BATON Pin Logic Input Low
VBAT > 2V
-
-
0.4
V
800
1000
1200
kΩ
10
-
-
mA
-
-
1
µA
OSCILLATOR PERIOD
Oscillator Period
tOSC
LOGIC INPUT AND OUTPUTS
BAT Pin Internal Pull-Down
Resistance
PPR, CHG
Driving Capability when LOW
Pin Voltage = 1V
Leakage Current When HIGH
Pin Voltage = 6.5V
NOTES:
6. The 4.0V VBAT is selected so that the CHG output can be used as the indication for the offset comparator output indication. If the VBAT is lower
than the POR threshold, no output pin can be used for indication.
7. The input current charge current can be affected by the thermal foldback function if the IC under the test setup cannot dissipate the heat.
8. Limits established by characterization and are not production tested.
3
FN6435.3
September 21, 2011
ISL9301
Block Diagram
To system load
To USB or AC Adatper
VIN
VOUT
1000
IOUT
IBAT
RILIM
1
VBAT
1000
Cell1
IREF
ILIM REF
1
VOUT
VOUT_REF
Die Temp
IBAT_REF
142 oC
Push 2S to turn on
VCC
VBAT
VBAT
IBAT
VBAT_REF
IREF
Die Temp
BATT ON
1V
BATT OFF
115 oC
BATON
TIME
COMP
S Q
R
SHUTDOWN
SHUTDOWN
VIN
VBAT
RTIME
0.2V
IOUT
COMP
IBAT
CLK
PPM CTRL
POR
Timer
EOC
Re-charge
OVP
DispIay
Logic
CHG
PPR
IMIN
RIMIN
To uP
GND
Pin Descriptions
VIN - Power input. The absolute maximum input voltage is
28V. A 10µF or larger value capacitor is recommended to be
placed very close to the input pin for decoupling purposes.
Additional capacitance may be required to provide a stable
input voltage.
VBAT - Charger output pin. Connect this pin to the battery. A
1µF or larger X5R ceramic capacitor is recommended for
decoupling and stability purposes. When the BATON pin is
pulled to logic LOW or left floating, the VBAT pin is
disconnected from the IC.
TIME - Timing resistor pin. The TIME pin determines the
oscillation period by connecting a timing resistor between
this pin and GND. The oscillator also provides a time
reference for the charger calculated in Equation 1.
t OSC = 75 × R TIME
( μs )
(EQ. 1)
Where RTIME is in MΩ. The nominal timeout interval is given
by Equation 2:
28
2 × t OSC
t TIMEOUT = ----------------------------3600
( Hour )
(EQ. 2)
PPR - Open-drain power presence indication. The
open-drain MOSFET turns on when the input voltage is
above the POR threshold but below the OVP threshold and
off otherwise. This pin is capable to sink 10mA (minimum)
current to drive a LED. The maximum voltage rating for this
pin is 7V.
CHG - Open-drain charge indication pin. This pin outputs a
logic LOW when a charge cycle starts and turns to HIGH
when the end-of-charge (EOC) condition is qualified. This
pin is capable to sink 10mA min. current to drive an LED.
When the charger is disabled, the CHG outputs high
impedance.
IMIN - End-of-charge (EOC) current program pin. Connect a
resistor between this pin and the GND pin to set the EOC
current. The EOC current IMIN can be programmed by
Equation 3:
3151
I MIN = ---------------R IMIN
( mA )
(EQ. 3)
Where RIMIN is in kΩ. The programmable range covers 5%
(or 10mA, whichever is higher) to 50% of IREF when
programmed to less than 5% or 10mA.
Where tOSC is in seconds. For an 1MΩ RTIME, the nominal
timeout interval is approximately 5.6 hours.
4
FN6435.3
September 21, 2011
ISL9301
IREF - Charge-current program and monitoring pin. Connect
a resistor between this pin and the GND pin to set the
charge current limit determined by Equation 4:
3886
I REF = ----------------R IREF
( mA )
(EQ. 4)
Where RIREF is in kΩ. The IREF pin voltage also monitors
the actual charge current during the entire charge cycle,
including the trickle, constant-current, and constant-voltage
phases. When disabled, VIREF = 0V.
BATON - Battery disconnect pin. The BATON pin is a logic
input pin to allow the disconnection of the battery from the
system to eliminate the unwanted drainage current from the
battery. There is an internal 1MΩ pull-down resistor at this
pin. Drive to HIGH to connect the battery to the system.
When this pin is driven to LOW or left floating, the battery is
disconnected from the system.
VOUT - Output connection to the system. This pin provides
a 4.5V regulated voltage for the system when a valid input
power is present. If no valid input is present, and BATON is
driven HI, the VOUT pin is connected to VBAT through an
internal MOSFET. If no valid input is present and BATON is
LOW, the voltage at VOUT pin is zero. A 4.7µF or larger X5R
5
ceramic capacitor is recommended for decoupling and
stability purposes.
EPAD - Exposed pad. Connect as much copper as possible
to this pad either on the component layer or other layers
through thermal vias to enhance the thermal performance.
TRICKLE
CC
4.2V
IREF
CV
CHARGE
VOLTAGE
VREC
CHARGE
CURRENT
2.8V
TIMEOUT
16%IREF
CHG
IMIN
CHG
INDICATION
TIME
FIGURE 1. TYPICAL CHARGING CYCLE
FN6435.3
September 21, 2011
ISL9301
Typical Application Circuit
INPUT
TO SYS
VOUT
VIN
C3
C1
VBAT
R3
BATT
C2
R1
ISL9301
R2
IREF
D1
RIREF
IMIN
PPR
TIME
CHG
GND
BATON
D2
RIMIN
RTIME
TO µP
PRESS AND HOLD 2s TO TURN ON
PART
DESCRIPTION
C1
10µF X5R ceramic capacitor
C2
1µF X5R ceramic capacitor
C3
4.7µF X5R ceramic capacitor
R3
1Ω, 5% resistor
RIREF
26.7kΩ, 1%, for 150mA charge current
RIMIN
137kΩ, 1%, for 23mA EOC current
RTIME
1MΩ, 1% resistor for 75µs clock period
R1, R2
470Ω, 5% resistor
D1, D2
LEDs for indication
Theory of Operation
When a valid input voltage is applied at VIN, the ISL9301
first regulates VOUT at 4.5V for system power need. In the
mean time, if the battery is attached, the ISL9301 also
charges the battery while supplying current to the system.
When the system exceeds the maximum available current,
either limited by the IC or by the input power supply, the
charger FET is operated in a reverse mode, i.e. it discharges
current to the system instead of charging.
The charger function is similar to other Li-ion battery
chargers, i.e. it charges the battery at a constant current
(CC) or a constant voltage (CV) depending on the battery
terminal voltage. The constant current IREF is set with the
external resistor RIREF, as shown in the “Typical Application
Circuit” on page 6. The constant voltage is fixed at 4.2V. If
the battery voltage is below a typical 2.8V trickle charge
threshold, the ISL9301 charges the battery with a trickle
current (~16% of the programmed constant current) until the
battery voltage rises above the trickle charge threshold.
When the battery voltage reaches the final voltage of 4.2V,
6
the charger enters the CV mode and regulates the battery
voltage at 4.2V to fully charge the battery without the risk of
overcharging. Upon reaching an end-of-charge (EOC)
current, the charger indicates the charge completion with the
CHG pin, but the charger continues to deliver 4.2V at the
VBAT pin until the timeout limit has reached. Figure 1 shows
the typical charge profile with the EOC/reset events.
The EOC current level IMIN is programmable with the
external resistor RIMIN. The CHG signal turns to LO when
the trickle charge starts and rises to HIGH at an EOC event.
After the EOC is reached, the CHG status is latched at HI.
The CHG status will be reset to logic LO when the VBAT
voltage drops to below the recharge threshold (4.05V), as
shown in Figure 1.
A thermal foldback function reduces the charge current
anytime when the die temperature reaches typically +115°C.
This function guarantees safe operation when the
printed-circuit board (PCB) is not capable of dissipating the
heat generated by the linear charger.
FN6435.3
September 21, 2011
ISL9301
The ISL9301 accepts an input voltage up to 28V but will be
disabled when the input voltage exceeds the OVP threshold,
minimum 10V, to protect against unqualified or faulty AC
adapters.
PPR Indication
The PPR pin is an open-drain output to indicate the
presence of the AC adapter. Whenever the input voltage is
higher than the POR threshold, the PPR pin turns on the
internal open-drain MOSFET to indicate a logic LOW signal.
When the internal open-drain FET is turned off, the PPR pin
should leak less than 1µA current. When turned on, the PPR
pin should be able to sink at least 10mA current under all
operating conditions.
The PPR pin can be used to drive an LED (see “Typical
Application Circuit” on page 6) or to interface with a
microprocessor.
Power-Good Range
The power-good range is defined by the following three
conditions:
1. VIN > VPOR
2. VIN - VOUT > VOS
3. VIN < VOVP
where VOS is the offset voltage for the input and output
voltage comparator and the VOVP is the overvoltage
protection threshold given in the "Electrical Specifications"
beginning on page 2. All VPOR, VOS, and VOVP have
hysteresis. The IC will not deliver any output if the input
voltage is not in the power-good range.
CHG Indication
The CHG is an open-drain output. The open drain FET turns
on when the charger starts to charge and turns off when the
EOC condition is qualified. Once the EOC condition is
qualified, the CHG signal is latched in off state. The EOC
condition is qualified when both of the following conditions
are satisfied:
1. VBAT > VRECHG
2. ICHG < IMIN
The CHG indication will not be turned on again until a
recharge condition is qualified. A recharge condition is
reached under one of the three conditions:
1. Input power being re-cycled
2. A recharge cycle starts when the battery voltage drops
below the recharge threshold
The CHG signal can be interfaced either with a
microprocessor GPIO or a LED for indication. A de-glitch
delay of 1ms for both edges is required to prevent nuisance
triggering due to some transient conditions.
7
Charge Termination, Recharge and Timeout
When an EOC condition is reached, the CHG pin changes to
logic HI to indicate the end-of-charge. However the charger
continues to deliver current to the battery until the timeout
interval has elapsed, then the charging will be terminated.
The setting of the timeout interval is described in “Intelligent
Timer” on page 8. When a recharge condition is met after a
timeout event, the timer will be reset to zero and the
charging re-starts.
In the event when the timeout interval has elapsed before
the EOC condition is reached, a timeout fault condition is
triggered. The timeout fault condition is indicated by the
CHG pin being toggled between HI and LO every 3s
(RTIME = 1MΩ). The timeout fault condition can be cleared
by removing and reapplying the input power to the IC.
Under the EOC, timeout and timeout fault conditions, the
power delivery to VOUT is not impacted. The battery
continues to supply current to VOUT if needed, as described
in “Dynamic Power Path Management” on page 8.
Battery Disconnection
The BATON pin provides an option for disconnection of the
battery from the system if battery power is not needed and
no power source is applied at VIN. The disconnection will
prevent the IC leakage current from draining the battery for
an extended period of time. To reconnect the battery, pull the
BATON pin to logic HI for 2s. Once the system is powered
on, the host micro process will send a logic signal to keep
BATON at logic HI level. The BATON pin has a 1MΩ internal
pull-down resistor thus, when left floating, the input is
equivalent to a logic LOW state. The logic threshold levels
are given in the "Electrical Specifications" table starting on
page 2.
BATON Interlock
When a valid voltage source is applied at VIN, the BATON
function is disabled. This prevents the battery from being
connected to a 4.5V regulated voltage source and
generating a large circulating current. If the VIN supply is
removed, the BATON function will resume immediately to
allow the battery to supply the system.
IREF Pin Function
The IREF pin has the two functions as described in “Pin
Descriptions” on page 4. When setting the fast charge
current, the charge current is trimmed to have 10% accuracy
at 145mA, excluding the programming resistor error. The
percent error decreases as the set charge current is higher
but increases as the set charge current is lower than 145mA.
The trickle charge current is 16% of the programmed fast
charge current.
When monitoring the charge current, the accuracy of the
IREF pin voltage vs the actual charge current has the same
accuracy as the gain from the IREF pin current to the actual
charge current. The IREF pin voltage vs the charge current
FN6435.3
September 21, 2011
ISL9301
when IREF is set to 145mA is shown in Figure 2. Figure 3
shows a typical time domain charge current curve vs time
and its accuracy limits for a complete cycle. The accuracy is
compared against the voltage on the IREF pin. Thermal
foldback may affect the charge current curve as well as the
accuracy.
current until VOUT is regulated. In the event that the system
needs more than the available current, VOUT will continue to
drop. When VOUT drops to below the battery voltage, the
DPPM control will turn on the charge control FET, allowing
the battery to supply current to the system load. Thus the
battery may be charged at a current smaller than the
programmed constant current.
Intelligent Timer
150
CHARGE CURRENT (mA)
The internal timer in the ISL9301 provides a time reference
for the maximum charge time limit. The nominal clock cycle
for the reference time is set by the external resistor
connected between the TIME pin and GND and is given by
Equation 1.
0
1 .2
IR E F P IN V O L T A G E (V )
FIGURE 2. IREF PIN VOLTAGE vs CHARGE CURRENT (IREF
IS SET TO 150mA. THE DOTTED LINES SHOW
THE UPPER AND LOWER LIMITS OF THE
TOLERANCE)
The nominal maximum charge time interval is calculated
based on the assumption that the programmed charge
current is always available during the entire charging cycle.
However, due to the PPM control or due to the current limit
of the input source, or thermal foldback, the actual charge
current maybe reduced during the constant current charge
period. Under such conditions, the Intelligent Timer control
will increase the timeout interval accordingly to allow
approximately the same mAh product as the original timeout
interval at the programmed current.
Thermal Foldback
ICHG
TRICKLE
CC
The thermal foldback function starts to reduce the charge
current when the internal temperature reaches a typical
value of +115°C. When thermal foldback is encountered, the
charge current will be reduced to a value where the die
temperature stops rising.
CV
1.1IREF
IREF
0.9IREF
1.3IMIN
0.22IREF
1.0IMIN
0.16IREF
0.7IMIN
0.12IREF
TIME
FIGURE 3. CHARGE CURRENT ACCURACY WHEN
IREF = 145mA
Dynamic Power Path Management
The power path management function of the ISL9301
controls the charge current and the system current when
charging with system load. This is based on the available
input current, which is either limited by the IC (800mA) or by
the input power source, whichever is smaller. When the
output voltage drops to the DPPM threshold (4.35V typical),
the dynamic power path management starts to function. The
DPPM control will first allocate the available current to the
system load, using the remaining current to charge the
battery. This is achieved by dynamically reducing the charge
8
Figure 5 shows the thermal foldback operation whereas the
current signals at the summing node of the current error
amplifier CA are shown in Figure 4. IR is the reference. IT is
the temperature tracking current generated from the
Temperature Monitoring block. The IT has no impact on the
charge current until the internal temperature reaches
approximately +115°C; then IT starts to rise. In the
meantime, as IT rises, ISEN will fall at the same rate (as the
sum is a constant current IR). As a result, the charging
current, which is proportional to ISEN, also decreases,
keeping the die temperature constant at +115°C.
The system output current, however, is not impacted by the
thermal foldback. Thus, when the charge current is reduced
to zero, if the die temperature still rises, the IC will shut down
to prevent damage to the IC.
FN6435.3
September 21, 2011
ISL9301
Q1
VIN
X3 VOUT
X3
Q2
X3
VBAT
TEMPERATURE
MONITORING
IT
ISEN
IR
REF
IREF
CONTROL
+
CA
-
VA
+
-
VREF
IREF
FIGURE 4. CHARGE CURRENT THERMAL FOLDBACK CIRCUIT
VOUT and VBAT Capacitor Selection
IR
IT
I SEN
-40mA/°C
The criteria for selecting the capacitor at the VOUT and
VBAT pins is to maintain the stability as well as to bypass
any transient load current. The recommended capacitance is
a 4.7µF X5R ceramic capacitor for VOUT and 1µF for VBAT.
The actual capacitance connected to the output is
dependent on the actual application requirement.
Layout Guidance
+115°C TEMPERATURE
FIGURE 5. CHARGE CURRENT FOLDBACK
Applications Information
Input Bypass Capacitor
The input capacitor is required to suppress the power supply
transient response during transitions. Typically, a 10µF or
larger capacitor should be sufficient to suppress the power
supply noise.
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 capacitor, a 1Ω series resistor
must be used (as shown in the “Typical Application Circuit”
on page 6) to provide adequate damping.
The ISL9301 uses a thermally-enhanced DFN package that
has an exposed thermal pad at the bottom side of the
package. The layout should connect as much as possible to
copper on the exposed pad. Typically, the component layer
is more effective in dissipating heat. The thermal impedance
can be further reduced by using other layers of copper
connecting to the exposed pad through a thermal via array.
Each thermal via is recommended to have 0.3mm diameter
and 1mm distance from other thermal vias.
Input Power Sources
The input power source is typically a well-regulated wall
cube with 1m length wire or a USB port. The input voltage
ranges from 4.3V to 10V. The ISL9301 can withstand up to
28V on the input without damaging the IC. If the input
voltage is higher than the OVP threshold, the IC is disabled.
State Diagram
The state diagram is shown in Figure 6. There are 8 states to
cover all the operation modes, including the Trickle Charge,
Batt Discharge, PPM, CV Charge, Charge Fault, Charge
Complete, Disabled and OTP states.
The IC starts with a trickle charge or constant current charge
state depending on VBAT when input power is applied. In the
Trickle Charge state, the PPR is LO and the CHG is LO,
9
FN6435.3
September 21, 2011
ISL9301
VOUT is regulated at 4.5V, the charger is ON, delivering a
trickle charge current.
The IC moves to a fast charge constant current mode when
VBAT reaches the VMIN threshold. There are 3 possible
states in this mode depending on the output current. When
the sum of the output current and the fast charge current is
smaller than the input current limit, the IC enters the Fast
Charge state with the charge current set by RIREF. When the
output current and the fast charge current are greater than
the input current limit, the IC will enter the PPM mode, where
the charging current is reduced to a point such that the sum
of output current and the charging current equals to the input
current limit. If the output current by itself is greater than the
input current limit, the IC enters the Battery Discharge state,
where the battery is discharged to the system to supply a
part of the output demand.
When the battery voltage reaches 4.2V, the IC enters the CV
Charge state, where PPR is LO, CHG is LO and VOUT is
regulated at 4.5V. The battery is being charged at a constant
voltage while the charging current decreases.
When the charging current is reduced to the IMIN threshold,
the IC enters a Charge Complete state, where PPR is LO,
CHG is HI, VOUT is regulated at 4.5V and the charger
continues to charge the battery.
When the timeout interval has elapsed after the Charge
Complete state, the IC will enter the Disabled state, where
the PPR is LO, CHG is HI, VOUT is regulated at 4.5V and the
charger is OFF. After the Charge Complete state, if VBAT is
below the re-charge threshold, the IC will re-initialize and
start a new cycle.
If the timeout limit is reached before the Charge Complete
state, the IC enters the Charger Fault state, where PPR is
LO, CHG is blinking, VOUT is regulated at 4.5V and the
charger is OFF. This state is latched until the input power is
removed and re-applied to start a new cycle.
Any time during the operation, if the die temperature reaches
the OTP threshold, the IC will enter the OTP state, where
PPR is LO, CHG is HI, and the charger is OFF. VOUT is
disconnected from VIN and connected to VBAT internally to
maintain system power need.
Summary of Output States
The output states under various fault conditions are
summarized in Table 1.
TABLE 1. OUTPUT STATES UNDER FAULT CONDITIONS
OTP
OVP
BATON
M1
M2
Y
Y
H
OFF
ON
Y
N
H
OFF
ON
N
Y
H
OFF
ON
Y
Y
L
OFF
OFF
Y
N
L
OFF
OFF
N
Y
L
OFF
OFF
N
N
X
Regulating
Charging
NOTES:
1. BATON: BATON Pin
2. OVP: Input Overvoltage Protection
3. OTP: Over-Temperature Protection
4. M1: Output Path MOSFET
5. M2: Battery Path MOSFET
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
FN6435.3
September 21, 2011
ISL9301
POW ER
UP
Y
N
IO U T >IL IM ?
V IN >V P O R ?
N
Y
Y
IR E F +IO U T >
IL IM ?
N
V IN <V O V P?
N
Y
B A T T D IS C H A R G E
VO UT = ON
IC H G = -(IO U T – IL IM )
CHARGER =
REVERSED
CHG = HI
T IM E R R E S E T
POR
N
V IN >V O U T +V O S?
Y
PPM
VOUT = ON
IC H G = (IL IM – IO U T )
CHARGER = ON
CHG = LO
FAST CHARG E
VO UT = ON
IC H G = IR E F
CHARG ER = ON
CHG = LO
N
V B A T = 4.2V ?
Y
IN IT IA L IZ A T IO N
R E S E T T IM E R
CV CHARGE
VO UT = ON
CHARGER = ON
CHG = LO
V B A T>V M IN
N
Y
T R IC K L E C H A R G E
PPR = L
CHG = L
V O U T = 4.5V
CHARG ER = ON
Y
CHARG ER FAULT
VO UT = ON
CHARG ER = O FF
C H G = B L IN K IN G
T IM E O U T?
N
I C H G < I M IN ?
N
Y
POW ER DOW N
TO PO W ER UP
CHARG E CO M PLETE
VO UT = ON
CHARG ER = ON
CHG = HI
T im eo u t?
N
Y
A N Y T IM E D IE
TEM PERATURE
E X C E E D S 142 O C
O TP
VOUT = VBAT
CHARG ER = OFF
CHG = HI
T d ie < 110 o C ?
D IS A B L E D
VO UT = ON
C h arg er = O F F
CHG = HI
N
Y
VOUT <
VRECH?
N
Y
FIGURE 6. STATE DIAGRAM
11
FN6435.3
September 21, 2011
ISL9301
Package Outline Drawing
L10.3x3C
10 LEAD DUAL FLAT PACKAGE (DFN)
Rev 2, 09/09
3.00
6
PIN #1 INDEX AREA
A
B
10
6
PIN 1
INDEX AREA
1
2.38
3.00
0.50
2
10 x 0.25
6
(4X)
0.10 C B
1.64
TOP VIEW
10x 0.40
BOTTOM VIEW
5
(4X)
PACKAGE
OUTLINE
0.10 M C B
SEE DETAIL "X"
(10 x 0.60)
(10x 0.25)
0.90
MAX
0.10 C
BASE PLANE
2.38
0.20
C
SEATING PLANE
0.08 C
SIDE VIEW
(8x 0.50)
1.64
TYPICAL RECOMMENDED LAND PATTERN
C
0.20 REF
5
0.05
DETAIL "X"
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 b applies to the metallized terminal and is measured
between 0.18mm 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.
7. COMPLAINT TO JEDEC MO-229-WEED-3 except for E-PAD
dimensions.
12
FN6435.3
September 21, 2011
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