Micrel MIC79110 User Manual
S
General Description
MIC79110
Simple 1.2A Linear Li-Ion Battery Charger
Features
The Micrel MIC79110 is a simple and accurate lithium ion
battery charger. The part features a built-in pass transistor,
precision programmable current limiting (±5%), and
precision voltage termination (±0.75% over temperature).
The MIC79110 packs full functionality into a small space.
Other features of the MIC79110 include two independent
indicators: a digital End-of-Charge signal that is
programmable with a resistor to ground, and an analog
current output that is proportional to the output current,
allowing for monitoring of the actual charging current.
Additional features include very low dropout (550mV over
the temperature range), thermal shutdown, and reverse
polarity protection. In the event the input voltage to the
charger is disconnected, the MIC79110 also provides
minimal reverse-current and reversed-battery protection.
Available in both fixed 4.2V and adjustable outputs, the
MIC79110 is offered in the leadless 10-pin 3mm x 3mm
®
MLF
with an operating junction temperature range of
–40˚C to +125˚C.
Data sheets and support documentation can be found on
Micrel’s web site at www.micrel.com.
• Input voltage range: 2.5V to 16V
• High output voltage accuracy of ±0.75%
over –5°C to +60˚C
• Current limit ±5% accurate from –5°C T
+ 125°C
J
• Programmable end-of-charge flag
• Analog output proportional to output current
• Adjustable and fixed 4.2V output
• Low dropout voltage of 550mV at 700mA load, over
temperature
• 1.2A max charge current
• Excellent line and load regulation specifications
• Reverse current protection
• Thermal shutdown and current limit protection
®
• Tiny 10-Pin 3mm × 3mm MLF
package
• Junction temperature range: –40°C to +125°C
Applications
• Cellular phones
• PDAs
• Digital cameras
• Camcorders
• MP3 players
• Notebook PCs
• Portable Meters
• Cradle chargers
• Car chargers
• Battery packs
___________________________________________________________________________________________________________
Typical Application
MIC79110
HUTDOWN
ENABLE
V
IN
V
SD
R
R
IN
EOC
SET
GND
BAT
SNS
D
A
EOC
CHG
4.2V
Li-Ion
Cell
4.2V
BAT
MIC79110 Typical Application
MLF and MicroLeadFrame are registered trademarks of Amkor Technology, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (
October 2007
408
) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
M9999-102507
Micrel, Inc. MIC79110
Ordering Information
Part Number
Standard Marking Pb-Free Marking
Voltage
Junction
Temp. Range
Package
MIC79110-4.2BML L942 MIC79110-4.2YML L942* 4.2V –40° to +125°C 10-pin 3×3 MLF®
MIC79110BML L9AA MIC79110YML L9AA* Adj. –40° to +125°C 10-pin 3×3 MLF®
* Pb-Free “Y” indicator is added to the device mark after LOGO.
Pin Configuration
1SD
2
R
SET
3
SNS
4
BAT
V
5
IN
Fixed Output
10-Pin 3mm × 3mm MLF
10 GND
R
9
EOC
8
D
EOC
7
A
CHG
V
6
IN
®
(ML)
1SD
R
2
SET
ADJ
3
BAT
4
V
5
IN
10 GND
R
9
EOC
D
8
EOC
A
7
CHG
V
6
IN
Adjustable Output
10-Pin 3mm × 3mm MLF® (ML)
Pin Description
Pin Number Pin Name Pin Function
1 SD Shutdown Input. Logic High = Off; Logic Low = On.
2 RSET
3 SNS (Fixed voltage only): Sense output, connect directly to battery.
3 ADJ (Adjustable voltage only): Feedback input.
4 BAT Battery Terminal. Connect to single-cell lithium-ion battery.
5, 6 VIN Input supply pin.
7 ACHG
8 DEOC
9 REOC
10 GND Ground
Current limit: Sets constant current limit via an external resistor to ground.
IR
= (0.2V/R
SET
Analog Charge Indicator Output: Current source who’s output current is equal to
1/1000 of the BAT pin current.
Digital End-of-Charge Output: N-Ch open drain output. Low indicates charging,
a current that is higher than the programmed current set by R
battery. When the current drops to less than the current set by R
goes high impedance, indicating end-of-charge.
End-of-Charge Set: Sets end-of-charge current threshold via an external resistor
to ground. I
SET
= (0.2V/R
EOC
) × 1000.
EOC
) × 1000.
is charging the
EOC
, the output
EOC
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Micrel, Inc. MIC79110
Absolute Maximum Ratings
(1)
Operating Ratings
(2)
Input Supply Voltage (VIN).................................... 0V to 18V
Shutdown Input Voltage (V) ................................. 0V to 10V
Output Voltage (ADJ) .....................................................10V
Power Dissipation ...................................Internally Limited
Junction Temperature ...............................–40°C to +125°C
Input Supply Voltage ........................................ 2.5V to 16V
Shutdown Input Voltage (V) ................................... 0V to 7V
Output Voltage (ADJ) .................................................... 9.6V
Junction Temperature Range (T
(MLF-10) .......................................................... 60°C
θ
JA
(MLF-10) ............................................................ 2°C
θ
JC
)............. –40°C to +125°C
J
Electrical Characteristics
TA = 25°C with VIN = V
otherwise specified.
Parameter Condition Min Typ Max Units
Output Voltage Accuracy
ADJ Pin Voltage Accuracy 0.5955 0.6 0.6045 V
Line Regulation
Load Regulation
Dropout Voltage(3)
Ground Current
VIN Pin Current SD = VIN
Shutdown Pin Current SD = 5.2V, V
Shutdown Input Threshold
Shutdown Hysteresis 60 mV
Current Limit Accuracy
Current Limit Setpoint
(5)
Range
Maximum Current Limit
V
Reverse Current VIN = High impedance or ground
BAT
Digital End–of–Charge (D
(6, 7)
I
I
D
D
D
R
R
EOC
(6, 7)
R
EOC
Logic–Low Voltage I
EOC
Leakage Current Logic High = VIN = 16V
EOC
On Resistance VIN = +5V
EOC
Maximum Current Limit R
EOC
Analog Charge Indicator (A
(8)
I
SOURCE
I
I
OUT
+ 1V; I
(4, 5)
EOC
CHG
(4)
= 100µA; C
LOAD
Variation from V
V
= V
+ 1V to 16V @ I
OUT
= 0.1mA to 1A
= 100mA, R
= 700mA, R
= 10mA, R
= 700mA, R
I
LOAD
I
LOAD
I
LOAD
I
LOAD
I
LOAD
IN
Logic High, regulator off
Logic Low, regulator on
V
= 0.9 × V
OUT
R
= 167, TJ = –40°C to +85°C
SET
V
= 0.9 × V
OUT
R
= 2k
SET
= 10µF; SD = 0V; R
BATT
= 4.2V; TJ = –5°C to +60°C; I
OUT
= 50mA -0.1
LOAD
= 167
SET
= 167
SET
= 167
SET
= 167
SET
= 0
BAT
; I
; I
OUT
OUT
= 1.2A,
= 0.1A,
NOM
NOM
=1k. Bold values indicate –40ºC < T
SET
= 50mA
LOAD
-0.75
-1.5
0.3 %
160
375
2 3 mA
24
120
0.1
1.1
-5
-20
< +125°C; unless
J
+0.75
+1.5
+0.1 %/V
250
550
35
300
5
%
%
mV
mV
mA
µA
µA
V
0.9
+5
+20
V
%
%
0.1 1.2 A
R
shorted to ground, V
SET
= 0.9 × V
BAT
NOM
1.25 1.65
4.2
2.5
20
A
µA
) Output
= 4k Current Falling
EOC
= 4k Current Rising
EOC
DEOC
= 5mA, I
= 700mA
BAT
35
50
30
50
70
40
0.74
65
70
95
100
0.95
mA
mA
mA
mA
V
0.1 µA
150 190
shorted to ground
EOC
0.5
1.0
2.0
mA
) Output
= 50mA
BAT
= 1.2A, TJ = –40°C to +85°C
BAT
37
800
46
950
55
1150
µA
µA
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Micrel, Inc. MIC79110
Notes:
1. Exceeding the absolute maximum rating may damage the device.
2. The device is not guaranteed to function outside its operating rating.
3. Dropout Voltage is defined as the input to output differential at which the output voltage drops 2% below its nominal value measured at 1V
differential. For outputs below 2.5V, dropout voltage is the input-to-output voltage differential with the minimum input voltage 2.5V. Minimum input
operating voltage is 2.5V.
4. V
5. IR
6. Output Current I
7. I
8. I
denotes the nominal output voltage.
NOM
= (0.2V/R
SET
than I
, D
EOC
= (0.2V/R
EOC
is the current output from A
SOURCE
) × 1000
SET
when Digital End-of-Charge output goes high impedance. Currents greater than I
EOC
is high impedance.
EOC
) × 1000
EOC
pin. A resistor to ground from the A
CHG
, the D
EOC
pin will program a voltage that is proportional to the output current.
CHG
output is low, currents lower
EOC
Block Diagram
SD
V
IN
R
SET
Thermal
Protection
Shutdown
Control
Current
Limit Set
Current
Limit Sense
+
V
REF
End of
Charge
Detect
A
CHG
R
MIC79110 Block Diagram
EOC
GND
BAT
SNS
D
EOC
Li-Ion
October 2007 4
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Micrel, Inc. MIC79110
Typical Characteristics
October 2007 5
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