SEMTECH SC805EVB

SC805
Miniature Integrated High Current
Lithium-Ion Battery Charger
POWER MANAGEMENT
Description
Features
The SC805 is a fully integrated, single cell, constant-current (CC)/constant-voltage (CV) Lithium-Ion battery
charger in a tiny 3x3 mm thermally enhanced lead free
MLP package. The SC805 can operate as a stand-alone
charger or in conjunction with a Power Management Controller (PMIC).
‹ Fully integrated charger with FET pass transistor,
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The SC805 has a pre-charge function for trickle charging
deeply discharged batteries. The fast charge current is
enabled automatically when the battery voltage reaches
the required threshold. When the battery reaches the
constant voltage or CV portion of the charge curve the
SC805 switches to CV regulation mode. In this mode
the output current decays as the battery charges until
the termination current is reached and the SC805 signals the charge cycle is complete. The SC805 can be
configured to continue charging for a predetermined time
before turning off, or to turn off immediately upon termination. After turning off its output, The SC805 enters
monitor mode. If the battery voltage drops by 100mV
from the CV voltage a new charge cycle will begin. The
timer function also protects against charging faulty batteries by turning off if the pre-charge time exceeds 1/4
of the total programmed charge duration.
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The SC805 also provides battery detection, and a battery NTC thermistor interface to disable charging when
the battery temperature exceeds safe-to-charge limits.
reverse-blocking diode, sense resistor and thermal
protection
High Accuracy Charge Current*
Tiny 3mm x 3mm 10 lead MLP package
Programmable precharge, fastcharge & termination
current
Battery voltage controlled to 1% accuracy
Built in timer for protection and complete charging
NTC interface with battery detection
Soft-start for step load and adaptor plug-in
Up to 1A continuous charge current
Input voltage range from 3V to 6V allows seamless
charging from current limited adapter
Provides adapter voltage VCCIL to power external
accessories
Battery Present detection and output indicator
Operates in charger or LDO-mode without battery
0.1µA battery drain current in shutdown and
monitor modes
Over current protection in all charging modes
CHRGB output communicates charging and end of
charge cycle
*Patent Pending
Applications
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The SC805 can also function as a general purpose current source or as a current source for charging nickelcadmium (NiCd) and nickel-metal-hydride (NiMH) batteries.
Typical Application Circuit
Cellular phones
PDA’s
Handheld meters
Charging stations
USB chargers
Digital cameras
Programmable current source
SC805 typical Application Circuit
CHARGER VIN
C1
1uF
D1
LED
Adapter
Present
Indicator
R1
3.01k
R2
3.01k
1
2
7
8
9
SC805
VCC
VOUT
VCCIL CHRGB
EN/NTC ITERM
NOBAT IPRGM
RTIME
GND
Charge
Complete
Indicator
3
10
5
4
6
D2
LED
R4
3.01k
RT1
Thermistor
R6
1k
t
BATTERY
LED
C1
R5
3.01k
R3
3.01k
D3
R7
2.2uF
1k
Charging
Indicator
August 22, 2005
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SC805
POWER MANAGEMENT
Absolute Maximum Ratings
Exceeding the specifications below may result in permanent damage to the device or device malfunction. Operation outside of the parameters
specified in the Electrical Characteristics section is not implied.
Parameter
Symbol
Maximum
Units
VCC, VCCIL, EN/NTC to GND
-0.3 to 7.0
V
VOUT, NOBAT, IPRGM, CHRGB, ITERM, RTIME to GND
-0.3 to +6.0
V
Power Dissipation
MLP (Derate 20mW/ °C above 85°C)
Pd
2
W
Thermal Impedance, Junction to Case
θJA
50*
°C/W
Junction Temperature
TJ
150
°C
Operating Ambient Temperature Range
TA
-40 to +85
°C
Peak IR Reflow temperature, soldering 20s-40s
TLEAD
260
°C
Storage Temperature Range
TSTG
-65 to 150
°C
Continuous
A
1
A
VOUT short to GND
IVCCIL + IVOUT Total Output Current
IOUT_TOT
*Calculated from package in still air, mounted to 3” to 4.5”, 4 layer FR4 PCB with thermal vias under the exposed pad per JESD51 standards.
Electrical Characteristics
Unless otherwise noted: VCC = 4.75V - 5.25V
Parameter
Symbol
Conditions
25oC
Min
Input Voltage
Typ
5
TA
(-40oC to +85°C)
Max
Units
Min
Max
3.15
5.9
V
ICCDIS
Shutdown Mode, EN = 0
0.1
1
µA
ICCCHG
Charging Mode
CHRGB, ITERM, IPRG = 0µA
1.2
2.25
mA
Battery Leakage Current
IleakBAT
V C C = 0V
0.1
1
µA
Regulated Voltage
VBAT***
V
Operating Current
Battery Pre-Charge Current
IPREQ
4.20
4.16
4.24
50
44
54
50
44.5
53.5
100
787
91.5
-5
111.5
+5
mA
%
1.0
A
ITERM Resistor R = 3.01k
Battery Termination Current
ITERMQ
Battery Fast-Charge Current
IFastQ1
IFastQ2
Battery Fast-Charge Max Current
Limit
IPRGM = 15k
IPRGM = 1.87k
VBATTERY = 3.8V
Dropout Voltage = 550mV
2.8V < VBATTERY < VBAT
mA
Iprog Regulated Voltage
VIPRGM
1.5
1.4
1.6
V
Iterm Regulated Voltage
VITERM
1.5
1.4
1.6
V
 2005 Semtech Corp.
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SC805
POWER MANAGEMENT
Electrical Characteristics (Cont.)
Parameter
Symbol
Conditions
25oC
Min
Typ
TA
(-40oC to +85oC)
Max
Units
Min
Max
6.4
7.5
V
5.9
7.15
V
Vin OVP Rising Threshold
VTOVPR
6.8
Vin OVP Falling Threshold
VTOVPF
6.4
Vin OVP Hysteresis
VTOVPH
375
150
Vin UVLO Rising Threshold
VTUVLOR
2.8
2.55
3.15
V
Vin UVLO Falling Threshold
VTUVLOF
2.75
2.5
3.1
V
Vin UVLO Hysteresis
VTUVLOH
50
30
Vbat Precharge Threshold
VTPREQR
2.8
2.7
2.9
V
Vbat Recharge Threshold
VTREQ
VBAT - VBATTERY
100
60
140
mV
Pre-Charge Fault Time-Out
TPQFAULT
Rtime=39.2k
38
30.7
44.7
min
Charge Complete Time-Out
TFASTQ
Rtime=39.2k
2.5
2.0
3.0
hrs
Timer Disable Threshold
VTTIMER
Rtime VIL Voltage
1.0
0.7
V
LDO-Mode Select Threshold
VTIINTTS
VCC-RTIME Voltage
1.1
0.7
V
VTDIS
SC805 disable
< 1.1
0.7
V
En-NTC Thresholds
6.0
mV
mV
VTNTCH
NTC Hot Vth Vcc=5
0.3VCC
0.294Vcc
0.314Vcc
V
VTNTCC
NTC Cold Vth Vcc=5
0.75VCC
0.736Vcc
0.756Vcc
V
VTNOBAT
No Battery Detect Vcc=5
0.95VCC
0.93Vcc
0.97Vcc
V
NTCHYS
Hot/Cold Hysteresis
50
OT
Hysteresis = 10°C
150
VCBVOH
Charge Complete
Isrc=2mA
4.5
4.3
5.0
V
VCBVOL
Charging Isnk=2mA
0.2
0.05
0.5
V
ICBOFF
Disable or LDO-mode
off leakage
0.1
1.0
µA
VNBVOH
EN=VCC, Isrc=1mA
4.8
INBOFF
EN=VCC/2 off leakage
0.1
VCCIL Resistance
VCCILR
R VCC to VCCIL, I=100mA
0.2
Reduced Fastcharge Current
IfqRed
Vout=3.8v, Rprog=1.87k
VCCIL load = 200mA
585
Over Temperature Shutdown
CHRGB LED Output
NoBat Output
mV
C
°
4.5
V
1.0
µA
W
545
625
mA
* Tied to PCB with 1 Square Inch, 2 Ounce Copper. Tja=41°C/W using JESD 51 Standard
** Charge current is reduced by VCCIL current. VCCIL current is not limited by the IC
*** Vbat load=75mA. See typical performance curves for load regulation.
 2005 Semtech Corp.
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SC805
POWER MANAGEMENT
Pin Configuration
Ordering Information
Device
Top View
VCC
1
10
VCCIL
2
9
RTIME
VOUT
3
8
NOBAT
IPRGM
4
7
EN/NTC
ITERM
5
6
GND
CHRGB
(1)
P ackag e
SC805IMLTRT(2)
MLP-10
S C 805E V B
Evaluation Board
Note:
(1) Only available in tape and reel packaging. A reel
contains 3,000 devices.
(2) Available in lead-free packaging only. This product
is fully WEEE and RoHS compliant.
MLP10: 3x3 10 Lead
Pin Descriptions
Pin #
Pin Name
1
VC C
2
VCCIL
Adapter input voltage. This pin provides a bias voltage approximately equal to the adapter
input voltage. The output current when charging will be reduced by the load current on VCCIL.
3
VOUT
Charger output, connect to battery.
4
IPRGM
Current limit program pin for charge and LDO-mode. Requires a resistor to ground to program
fast-charge current.
5
ITERM
Selection for current termination and pre-charge current. Requires a resistor to ground to
program pre-charge and termination current.
6
GND
7
EN/NTC
Combined device enable/disable and NTC input pin. Logic low disables the device. Analog
voltages between 0.3VCC and 0.75VCC enable the NTC function. Voltages above 95% of
VCC force the NOBAT output high.
8
NOBAT
Battery Present Indicator. This output goes high when the NTC voltage exceeds 95% of VCC
indicating the Battery and NTC have been removed.
9
RTIME
Charge time programming resistor. Connect a resistor between RTIME and GND to program
the charge time. Force the pin to GND to disable the timer. Force the pin to VCC to select
LDO-mode.
10
CHRGB
Output status indicator designed to drive two LEDs. Connect cathode of the 'charging' led to
this pin to indicate charge in progress. Connect the anode of the 'charge complete' led to this
pin to indicate charge complete.
 2005 Semtech Corp.
Pin Function
Supply pin, connect to adaptor power.
Ground
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SC805
POWER MANAGEMENT
Block Diagram
VCC
1
Reference
Voltages
Vout Ref
Fast Charge Ref
VCCIL
Pre-Charge Ref
GND
6
Control
2
Pre-Charge On
Fast-Charge On
Over Temp
NOBAT
Under Voltage
8
Over Voltage
EN/NTC
7
NTC
Interface
VOUT
Timer
RTIME
3
9
IPRGM
CHRGB
10
4
Fast Charge Ref
ITERM
VOUT
5
Vout Ref
 2005 Semtech Corp.
Pre-Charge Ref
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SC805
POWER MANAGEMENT
Applications Information
Fast-Charge Mode (CC)
The fast-charge or CC mode is active when the battery
voltage is above 2.8V and less than the CV or final float
charge voltage of the battery. The fast-charge current
can be set to a maximum of 1.0A and is selected by the
program resistor on the IPRGM pin. The voltage on this
pin will represent the current through the battery enabling
a microprocessor via an analog-to-digital converter (ADC)
to monitor battery current by sensing the voltage on the
IPRGM pin. The equation to set the fast-charge current
is given by:
General Operation
The SC805 is configured based on the application for
Fast Charge and Termination current, timing requirements, and operation with and without a battery (LDO
mode). A typical charging cycle is described below. Details on alternate applications and output programmability are covered in the individual sections.
The charging cycle begins when the adapter is plugged
in. The SC805 performs glitch filtering on the VCC input
and initiates a charge cycle when VCC > UVLO. At this
time, the CHRGB signal is active low turning on the charging LED. If the battery voltage is less than 2.8V, the
SC805 will charge the output with the pre-charge current. When the battery voltage exceeds 2.8V, the SC805
enters fast-charge or constant current (CC) mode. When
the battery voltage reaches its final value, the charger
enters the constant voltage (CV) mode. In this mode the
output current decreases as the battery continues to
charge until the termination current level is reached.
 1.5 
 • 1000
FCI = 
 R PRGM 
Note that for a given program resistor the current through
the battery in CV mode can be determined by replacing
1.5 with the actual voltage on the IPRGM pin in the above
equation.
The superior fast-charge current accuracy of the SC805
is obtained by use of a patented* polarity-switched (i.e.,
chopped) current sense amplifier to nullify current measurement offset errors.
The CHRGB pin goes high when Iout is less than
Itermination turning off the ‘charging’ LED and turning
on the ‘charge complete’ LED. The SC805 continues to
hold the battery in CV charge mode until the timer expires. At this point the charger enters the monitor mode
where the output remains off until Vout drops by 100mV
and a new charge cycle is initiated.
Termination Current
Once the battery reaches the program voltage of 4.2V
the device will transition from a constant current source
to a constant voltage source and the current through
the battery begins to decrease while the voltage remains
constant. When the current falls below the programmed
termination current set by the termination resistor on
the ITERM pin, the SC805 will transition the CHRGB pin
from low to high. If the timer is enabled the output will
continue to float charge in CV mode until the timer expires. If the timer is disabled than the output will turn off
as soon as the termination current level is reached. If
the part is in LDO mode the SC805 will remain on indefinitely at the regulated CV voltage. The equation to set
the termination current is given by:
Pre-Charge Mode
Pre-charge mode is automatically enabled whenever the
battery voltage is below 2.8V. It is used to limit the power
dissipation and precondition the battery for fast charging. The pre-charge current value is selected by the resistor on the ITERM pin. The pre-charge current is programmable from 10mA to 125mA. The equation to select the pre-charge current is given by:
 1.5
PCI = 
 R TERM

 • 100

 1.5
ITERM = 
 R TERM
If the charge timer is in use there is also a maximum
allowed pre-charge duration. If the pre-charge time exceeds 1/4 of the total charge cycle the charger will turn
off due to a pre-charge fault. This fault is cleared when
EN or VCC is toggled or the output voltage rises above
2.8V.

 • 100

Monitor Mode
When a charge cycle is completed, the SC805 output
turns off and the device enters monitor mode. If the
voltage of the battery falls below the recharge threshold
*US Patent 6,836,095
 2005 Semtech Corp.
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SC805
POWER MANAGEMENT
Applications Information (Cont.)
of CV-100mV the charger will clear the charge timer and
re-initiate a charge cycle. The maximum current drain of
the battery during monitor mode will be no more than
1µA over temperature. The status of the charger output
as a function of RTime, and IOUT is shown below.
Output
State
Rtime
Timer
Iout
On
VC C
N/A
N/A
On
R
T < Timer
N/A
Off
R
T > Timer
N/A
On
Low
Disabled
> Itermination
Off
Low
Disabled
< Itermination
NOBAT output
The SC805 detects the absence of the battery by monitoring the voltage on the NTC pin. When the NTC pin
voltage exceeds 95% of VCC the NOBAT output is driven
high. This function utilizes the standard NTC configuration with the NTC component residing in the battery pack.
When the battery is removed the NTC element in the
resistor divider is missing and the NTC voltage is pulled
up to VCC.
The NOBAT output can be used to signal the system that
the battery has been removed, drive an external LED, or
fed back to the SC805 to select LDO-mode.
Connect the NOBAT pin to the RTIME pin to select LDO
mode when the battery is removed and re-enable the
output of the SC805.
LDO Mode
The SC805 is designed to work with or without a battery.
If the battery is not in place the device can enter LDO
mode. In this mode the SC805 will act like a low dropout
regulator. The input pin RTIME is used to select LDO
mode. If RTIME is high the device will be in LDO mode.
When LDO-mode is selected and the EN-NTC pin is greater
than 90% of VCC the output will be on in LDO mode.
During LDO mode the device will regulate the output voltage with a current limit set by the resistor tied to the
IPRGM pin.
Charge Timer
The timer on the SC805 is used as protection in the case
of a faulty battery and to maximize charging capacity.
Connect a resistor from the RTIME pin to GND to select
the desired charge time duration according to the following equation.

R
Charge Time =  TIME  • 2.5hrs
39.2k


The timer is programmable over the range of 1 to 10
hrs. To disable the charge timer connect RTIME to GND.
Driving the RTIME pin to VCC will disable the timer and
select LDO-mode operation for the SC805. One implementation of this feature is discussed in the NOBAT operating section.
EN-NTC Interface
The Enable pin on the SC805 provides three functions;
device disable, battery detection, and NTC temperature
protection. It can be used to turn off the device by driving the pin to Ground. It can also be connected to an
external resistor divider consisting of a resistor and an
NTC Thermistor to disable the charge cycle when the temperature is out of range. If the pin is pulled to VCC the
SC805 will signal a ‘No Battery’ condition on the NOBAT
pin. Note that the SC805 will be disabled due to the
NTC function when the ‘No Battery’ condition is detected
due to the NTC feature. The NTC temperature fault can
be overridden to re-enable the output of the charger for
no battery conditions as described in the NOBAT section
of the datasheet.
The SC805 will automatically turn off the output when
the charge timer times out.
 2005 Semtech Corp.
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SC805
POWER MANAGEMENT
Applications Information (Cont.)
The NTC external component configuration is shown in
the typical application schematic on page 1 of the
datasheet. When the NTC voltage from the divider is
above or below the cold and hot temperature threshold
values the SC805 will suspend the charge cycle by turning off the output, freezing the charge timer, and indicating a fault on the CHRGB LED. Hysteresis is included for
both hot and cold thresholds to avoid chatter at the NTC
trip points. When the temperature returns to the valid
range the SC805 will automatically resume the charge
cycle. The charge timer will time-out when the SC805
output on-time exceeds the timer setting regardless of
how long it has been disabled due to the NTC temperature. The internal NTC thresholds of 30% and 75% VCC
were designed to work with Curve-2 type thermistors
available from numerous vendors.
The closest standard resistor value is 9.53k. RT(temp)/
RT(25oC) is often referred to as the ratio at the given
temp. For this NTC at 50oC the ratio is 0.4086.
Design Example based on the typical application schematic of page 1 using a Curve 2 Vishay-Dale NTC.
CHRGB LED Flag
The CHRGB LED driver on the SC805 can be used to
drive two external LEDs: CHRGB=Low (Charging) and
CHRGB=High (Charge Complete). The CHRGB output
will be high impedance when the VCC is in a UV condition. The Table below defines the CHRGB LED output
states.
Step 3: Calculate the Tcold value.
 RTCOLD

 RT25

R2 
 = 3 • 
 = 2.86
 10K 

The ratio for the curve 2 NTC at 0oC is 2.816. The difference represents less than 1/2oC (i.e., actual trip would
be -0.5oC instead of 0oC.) For temperature trip values
other than 0oC and 50oC alternate curve-type NTC elements can be used or an additional resistor can be added
to the Rntc divider to alter the temperture coefficient.
Thot = 50oC
Tcold = 0oC
Find R2 and RT1
Step 1: Pick an RT1 value high enough to prevent selfheating.
RT1 ≥
(V (R T 1 ))2
DC
In general lower values of RT1 provide more noise immunity for the NTC voltage at the expense of bias current
from the input adapter. The dissipation constant DC is
the power rating of the NTC resulting in a 1oC self heating error.
LE D
High
Low
High-Z
Blinking
CHRGB
Iout < Iterm
Iout > term
VCC<UV
PreCharge
OV or NTC
Fault
The CHRGB output can be used for a VCC indicator. When
the SC805 is enabled the CHRGB output is either high
or low providing the VCC input is above UVLO.
The DC value for this NTC is 3mW and the voltage across
the NTC is 2.5V for a 5V adapter. Therefore RT1 > 2K,
The CHRGB output signifies the charging status. When
the output current is > Itermination, CHRGB=low. CHRGB
is high when Iout is < Itermination. The CHRGB output is
latched high at the end of the charge cycle when the
output current is less than Itermination. The CHRGB
output will remain high until the timer expires and vbatt
enters a re-charge cycle, or if EN, or VCC are toggled.
Set RT1 = 10k
Step 2: Find R2 to set the correct Hot level trip point,

 R T50  
  = 9.52k
R2 = 2.33 •  R T25 * 
R  

T25



 2005 Semtech Corp.
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SC805
POWER MANAGEMENT
Applications Information (Cont.)
Layout Guidelines
The two most critical aspects of the pcb layout are the
power path and thermal layout. The power path starts
at the Adapter + input and runs to the VCC input of the
SC805, then from the Vout pin of the SC805 to the Battery + terminal, and completes with the return trace from
the battery - terminal to the adapter - input. All of these
traces need to be designed to handle the required charging current. The trace from Vout of the SC805 is most
critical and should be made as wide as possible to minimize IR drops between the regulated voltage at the
SC805 vout pin and the battery terminal. Keep the
Adapter+ to SC805 VCC input trace wide to minimize
voltage drops that will add to the dropout voltage of the
SC805. The GND pin of the SC805 should be connected
in a kelvin fashion at the Battery-terminal to eliminate
voltage drops in the return path which reduce the regulated battery voltage.
The CHRGB indicator operates the same way in both
charge and LDO mode.
The CHRGB output can be used for a VCC indicator. When
the SC805 is enabled the CHRGB output is either high
or low providing the VCC input is above UVLO. Alternately
an LED connected to VCCIL can be used for a VCC indicator as shown in the typical application schematic on
the front page of the datasheet.
There are five fault modes detected by the SC805; (Input under voltage, input over voltage, NTC temperature,
Max die temperature or OT and pre-charge timeout). The
LED states for these fault modes are shown below.
Fault
CHRGB
V C C U V LO
High-Z
VCC OVP
Blinking
NTC Fault
Blinking
Pre-Charge Time-out
Blinking
T j > 150oC
Blinking
The thermal performance of the SC805 package requires
a low impedance connection from the heat slug on the
bottom of the package to an external ground plane. This
is best accomplished by using a single large via under
the device connected to a ground plane on the bottom
exposed side of the pcb. The evaluation board uses 1
square inch of copper on the bottom of the pcb and is
capable of 1A charging current.
Overcurrent and Max Temperature Protection
Overcurrent protection is inherent in all modes of operation. When the device is in charge-mode the output is
current limited to either the pre-charge current limit value
or the fast charge current limit value depending on the
voltage at the output. When the device is in LDO mode
the output current is limited to the fast charge current
limit. Max die temperature protection is included on the
SC805. This feature allows the SC805 to operate with
maximum power dissipation by disabling the output current when the die temperature reaches OT. The result is
that the SC805 will operate as a pulse charger in extreme power dissipation applications delivering the maximum allowable output current while regulating the internal die temperature to a safe level.
 2005 Semtech Corp.
The input and output bulk decoupling capacitors for the
SC805 should be placed near the external terminals for
the adapter and battery. This short low impedance loop
is for the high current spikes that result from input/output hot-plugging of the charger. To minimize these current spikes the value of the decoupling capacitor should
be minimized. A typical application requires a 0.1µF input/output capacitor. If the distance from the external
terminals to the SC805 is greater than 1”, 0.1µ local
decoupling capacitors at the SC805 may be required.
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SC805
POWER MANAGEMENT
Evaluation Board Schematic
Vout+
1
R806
R805
No Pop
0
R4
1e6
Charge
Complete
Indicator
C2
1uF
D1
D2
LED
LED
CHRGB VCCIL
1
D3
R12
3
10
2
8
7
1
EN-NTC
1k
Charging
Indicator
R2
1k
0
VOUT
VCC
CHRGB RTIME
VCCIL
ITERM
NOBAT IPRGM
EN-NTC
GND
CHRG+
1
9
5
4
6
1
No Pop
1
R1
SC805
R7 No Pop
R3
2.2uF
R8 No Pop
No Pop
Adapter
Present
Indicator
C1
NOBAT
IPGM
1
R6
3.01K
1
R5
1e6
VOUT-
R9
3.01K
ITRM
1
R10
3.01K
RTIME
1
R11
40K
CHRG1
1
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SC805
POWER MANAGEMENT
Typical Characteristics
B a tte ry C h a rg e P ro file
0 .4
0 .3
0 .2
0 .1
V C HA RGE
V C HRGB
3:45:00
3:32:30
3:20:00
I C HA RGE
Fast Charge Current -vs- Rprgm Value
Pre-Charge/Termination Current -vs- Rterm
900
90
800
80
FastC harge C urrent
Output Current (mA)
700
600
500
400
300
200
100
Pre-Charge Current
70
60
50
40
30
20
10
30000
Charge Tim er -vs- Rtim e
V drop
80
4
60
3
40
2
1E+05
1E+05
0
90000
0
70000
20
50000
1
30000
Pre-Charge Time-out
(min)
100
5
15000
Drop-out Voltage (V)
120
6
30000
7500
0.2
0.65
0.6
0.55
0.15
0.05
0.5
0.45
0.4
0.35
0
0.3
0.25
0.1
100
250
500
Output Current (mA)
Rtim e (ohm s)
 2005 Semtech Corp.
0.75
0.7
R out
Drop-out Resistance
(ohms)
8
Fast-C harge Tim eout
5000
Drop-out Voltage f(Iout)
0.25
140
Pre-C harge Tim e-out
3750
Rterm Value (ohms)
9
7
15000
Rpgrm Value (ohms)
3000
2500
2140
0
1870
15000
7500
5000
3750
3000
2500
2140
1870
0
Fast-Charge Time-out
(hrs)
3:07:30
2:55:00
T IM E
VCHRGB voltage not to
scale, shown to indicate
timing.
Output Current (mA)
2:42:30
2:30:00
2:17:30
2:05:00
1:52:30
1:40:00
1:27:30
1:15:00
1:02:30
0:50:00
0:37:30
0:25:00
0:12:30
0
0:00:00
VOLTAGE (Volts)
0 .5
CURRENT (Amps)
0 .6
4 .4
4 .2
4
3 .8
3 .6
3 .4
3 .2
3
11
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SC805
POWER MANAGEMENT
Typical Characteristics (Cont.)
Fast Charge Current Line Regulation f(vout)
501
4.00%
500
3.00%
499
2.00%
498
1.00%
497
0.00%
496
-1.00%
495
-2.00%
494
-3.00%
FastCharge Current
FastCharge Error(%)
4.00%
500
3.00%
2.00%
499
1.00%
0.00%
498
-1.00%
497
496
-4.00%
-5.00%
0.04%
4.207
0.02%
4.206
0.00%
4.205
-0.02%
4.204
-0.04%
Unloaded Vout
Loaded Vout
Unloaded Error(%)
Loaded Error(%)
-0.01%
4.21
Output Voltage (V)
4.208
0.06%
0.00%
4.211
Percent Error (%
Output Voltage (V)
0.08%
-0.06%
-0.02%
4.209
-0.03%
4.208
-0.04%
-0.05%
4.207
4.206
Loaded Vout
-0.06%
Loaded Error(%)
-0.07%
-0.08%
4.205
-0.08%
-0.09%
-0.10%
4.204
-0.10%
500
450
400
350
300
250
200
150
100
50
0
6.5
Output Current (mA)
Input Voltage VCC (V)
Pre-Charge Current Limit, Vcc < 4.2V
CC Current Limit, Vcc < 4.2V
510.0
5.00%
51.0
5.00%
490.0
0.00%
49.0
0.00%
470.0
-10.00%
430.0
Fast-Charge Current
% Error
410.0
-15.00%
-20.00%
390.0
Percent Error
450.0
Output Current (mA)
-5.00%
47.0
-5.00%
45.0
-10.00%
43.0
Pre-Charge Current
% Error
41.0
-15.00%
-20.00%
39.0
5.5
5
5.5
Input Voltage Vcc (volts)
Input Voltage Vcc (volts)
 2005 Semtech Corp.
4.5
-30.00%
4
35.0
3.5
-30.00%
3
350.0
5
-25.00%
4.5
37.0
4
-25.00%
3.5
370.0
3
Output Current (mA)
4.20
4.15
4.10
4.209
6.0
4.00
Output Voltage Load Regulation f(Iout)
0.10%
5.5
3.80
Output Voltage Line Regulation f(Vin, Iout)
4.21
5.0
3.60
Output Voltage Vout (V)
Input Voltage VCC (V)
4.5
3.40
6.5
3.20
3.00
4.3 4.5 4.7 4.9 5.1 5.5 5.75 6
4.201
-3.00%
495
-5.00%
4.202
-2.00%
FastCharge Error(%)
-4.00%
492
4.203
FastCharge Current
Percent Error (%
493
5.00%
501
Percent Error (%
5.00%
Output Current (mA)
502
Percent Error (%)
Output Current (mA)
Fast Charge Current Line Regulation f(vin)
12
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SC805
POWER MANAGEMENT
State Diagram
Under Voltage will force the
SC805 into Shutdown Mode
from any state.
Shutdown Mode
Vout/Iout off
CHRGB High Z
OVP> Vin > UVLO
Over Voltage will disable
the output, suspend the
timer, and blink CHRGB
En=Hi
Yes
Soft Start Vout
CC=Constant Current
CV=Constant Voltage
CHRGB Low
Timer
Enabled?
Yes
Soft Start CC Mode
Start Timer
Iout=1500/Rprog
Time=0
Start Pre-Charge
Vout=CV
Yes
Yes
Vout>2.8V
Start CV Mode
Iout=150/Rterm
Timer
Enabled?
Iout<Iterm
Yes
Time>Tmax/4
Yes
CHRGB High
Yes
Iout<Iterm
CHRGB High
Yes
Monitor Mode
Vout=off
Yes
Vout< CV-100mV
 2005 Semtech Corp.
Yes
Time>Tmax
Yes
Pre-Charge
Timeout Fault
CHRGB blinks at 1Hz
Cleared by
Vbat>2.8V or
Re-cycle EN or VCC
Time>Tmax
0oC > NTC Temp >50oC
Float Charge Mode
Vout = CV
NTC out of Range Fault
CHRGB blinks at 1Hz
Timer is frozen
Charge resumes when NTC
Temperature is valid
13
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SC805
POWER MANAGEMENT
Outline Drawing - MLP3x3-10
A
E
DIMENSIONS
INCHES
MILLIMETERS
DIM
MIN NOM MAX MIN NOM MAX
B
A
A1
A2
b
C
D
E
e
L
N
aaa
bbb
E
PIN 1
INDICATOR
(LASER MARK)
A
aaa C
A1
C
1
.039
.031
.002
.000
(.008)
.007 .009 .011
.074 .079 .083
.042 .048 .052
.114 .118 .122
.020 BSC
.012 .016 .020
10
.003
.004
0.80
1.00
0.00
0.05
(0.20)
0.18 0.23 0.30
1.87 2.02 2.12
1.06 1.21 1.31
2.90 3.00 3.10
0.50 BSC
0.30 0.40 0.50
10
0.08
0.10
SEATING
PLANE
C
A2
2
LxN
D
N
e
bxN
bbb
C A B
NOTES:
1. CONTROLLING DIMENSIONS ARE IN MILLIMETERS (ANGLES IN DEGREES).
2. COPLANARITY APPLIES TO THE EXPOSED PAD AS WELL AS TERMINALS.
Marking Information
805I
yyww
Top view.
Marking for the SC805 MLP 10 Lead package:
yyww = Date Code (Example: 0349)
 2005 Semtech Corp.
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SC805
POWER MANAGEMENT
Land Pattern - MLP3x3-10
K
DIM
(C)
H
G
Y
X
Z
C
G
H
K
P
X
Y
Z
DIMENSIONS
INCHES
MILLIMETERS
(.112)
.075
.055
.087
.020
.012
.037
.150
(2.85)
1.90
1.40
2.20
0.50
0.30
0.95
3.80
P
NOTES:
1.
THIS LAND PATTERN IS FOR REFERENCE PURPOSES ONLY.
CONSULT YOUR MANUFACTURING GROUP TO ENSURE YOUR
COMPANY'S MANUFACTURING GUIDELINES ARE MET.
Contact Information
Semtech Corporation
Power Management Products Division
200 Flynn Road, Camarillo, CA 93012
Phone: (805)498-2111 FAX (805)498-3804
 2005 Semtech Corp.
15
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