LX2208
EVALUATION BOARD USER GUIDE
LX2208 THREE LEVEL BATTERY
CHARGER (2A MAXIMUM)
8
8
®
TM
Copyright © 2007
Rev. 1.0a, 2007-06-05
Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 1
LX2208
EVALUATION BOARD USER GUIDE
INTRODUCING TO PRODUCT
The LX2208 Evaluation Board is available from Microsemi for evaluating the performance of the LX2208 Battery
Charger Integrated Circuit. The component sizes used on the evaluation board facilitate easy probing, however, in
practice, smaller component sizes are recommended to minimize the circuit physical size.
KEY FEATURES
Up to 2A Charging Current
Integrated Power MOSFET
Three Charge Levels for Adapter, and USB Hi and Low
Charge Battery from a Current Limited Adapter
0.5% Battery Voltage Accuracy
USB Current Compliance
Battery Full Indicator
CC/CV with Thermal Feedback
Battery Temperature Monitor
Precision Charge Termination
o
o
o
o
o
o
Protection features:
Unsafe Battery Temp Lockout
Internal IC Temp Regulator
USB Current Limiter
Reverse Current Blocking
Under Voltage Lockout
False Termination Prevention under Low Supply Conditions
APPLICATIONS
Navigation Devices
Multi-Media Players
Handheld Devices
Digital Cameras
PART SPECIFIC INFORMATION
Part Number
Product
LX2208ILD
Three Level Lithium Ion Battery Charger
TABLE 1 – PART INFORMATION
IC
LX2208ILD
EVALUATION BOARDS
LX2208 EVAL KIT
TABLE 2 – EVALUATION BOARD INFORMATION
Copyright © 2007
Rev. 1.0a, 2007-06-05
Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 2
LX2208
EVALUATION BOARD USER GUIDE
SCHEMATIC FOR LXE
STATUS
R6
2.49k
1
PWR
C1
10uF
GND
C3
R12 2
0.47u
1.00k 8
6
R1
1.00k
H
9
R11
1.00k
3
R3
2.49k
4
R7
CMP
H/L
20%
LX2208
DCOK
TMP
SD
10
500mA
IN
5
L
POWER SELECT
STAT
BAT
11
2.49k
12
HCP
LCP
CHARGING
FULL
POWER
ATTACHED
R8
121k
R9
Not
Used
R10
24.9k
GND
7
Battery
Temperature
Lockout
Sensing
NTC
RT1
100mA
RTN
USB
BAT TEMP
R2
1.00k
OFF
BAT+
ON
SHUTDOWN
R5
3.57k
R4
15.8k
C2
10uF
RTN
Current
Programming
BATTERY
Figure 1 – LX2208 Evaluation Board Schematic
Copyright © 2007
Rev. 1.0a, 2007-06-05
Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
LX2208
EVALUATION BOARD USER GUIDE
IC BLOCK DIAGRAM
Copyright © 2007
Rev. 1.0a, 2007-06-05
Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 4
LX2208
EVALUATION BOARD USER GUIDE
+
SD
5
ENABLE
DCOK
4
UVLO
TMP
11
STAT
3
CHARGE
CONTROL
CMP
2
IN
BAT
1
12
CHARGE
TERMINATION
CONTROL
CONSTANT
VOLTAGE
CONTROL
TEMPERATURE
CONTROL
CONDITIONING
THRESHOLD
H/L
8
COND.
CURRENT
20%
6
LCP
9
HCP
10
LOW
CHARGING
CURRENT
HIGH
CHARGING
CURRENT
GND
7
Figure 2 – Simplified Block Diagram
Copyright © 2007
Rev. 1.0a, 2007-06-05
Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 5
LX2208
EVALUATION BOARD USER GUIDE
LX2208 EVAL
Connections. The LX2208 Evaluation Board has
one power input and one power output connection.
FUNCTION
PIN NAME
2) Move the SHUTDOWN jumper to the ON
position, the USB jumper to the 500mA
position and the POWER SELECT jumper to
the WALL position.
3) Apply a +5V power source to the PWR
terminal and the power supply return to the
GND terminal.
VOLTAGE
4) The POWER ATTACHED and CHARGING
LEDs should be lit when the battery is
charging and the POWER ATTACHED and
FULL LEDs should be lit when the battery is
fully charged.
Input Power
PWR
5V +/- 0.65V
Input RTN
GND
0V
Battery +
BAT+
0V to 4.3V
5) Monitor the charge current into the battery
with a current probe.
Battery -
RTN
0V
6) Verify the charge current changes from
approximately 2A to approximately 460mA
when the POWER SELECT jumper is
moved from the WALL to the USB position.
Jumpers. The LX2208 Evaluation Board has three
two position jumper blocks. The jumper can be
moved to select either a high logic level or low logic
level. It is also possible to remove the jumper and
apply a voltage directly to the center pin of the
jumper block.
Hookup. The following is a demonstration scenario
that can be used to evaluate the LX2208.
1) Apply the single cell Lithium Ion or Lithium
polymer battery to the battery screw terminal
block. Be sure to connect the positive
terminal of the battery to the BAT+ terminal
and the Negative terminal to the RTN
terminal.
Copyright © 2007
Rev. 1.0a, 2007-06-05
7) With the POWER SELECT jumper in the
USB position, verify the charge current
changes from approximately 460mA to
approximately 92mA when the USB jumper
is moved from the 500mA position to the
100mA position.
8) Verify that moving the SHUTDOWN battery
to the OFF position extinguishes the LEDs
and terminates the charge cycle.
9) The thermal lockout can be tested by
momentarily applying a jumper between the
RTC and RTN on the BAT TEMP jumper
terminal. When the jumper is in place, the
charging current will drop to zero, but the
charge LED will remain illuminated.
Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 6
LX2208
EVALUATION BOARD USER GUIDE
LX2208 TYPICAL TEST HOOKUP
Single Cell
Lithium Ion
Battery
+
+
5V Power
Supply
Figure 3 – LX2208 Typical Test Hookup
PCB LAYOUT RECOMMENDATIONS
It is recommended that C1and C2 be located within
1cm of the LX2208. The CMP capacitor and resistor
(C3 and R12) should be located close to the IN and
CMP pins. Also the high impedance summing node
connecting to the TMP pin should be kept relatively
short to prevent the coupling of noise into this node. It
is important that the LX2208 have a good thermal
path to ambient to dissipate heat. The simplest way
to do this is to heatsink the LX2208 bottom pad
Copyright © 2007
Rev. 1.0a, 2007-06-05
directly to the ground plane by placing 4 or more vias
in the ground pad directly under the LX2208 footprint.
Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 7
LX2208
EVALUATION BOARD USER GUIDE
LX2208 PRINTED CIRCUIT BOARD LAYOUT
Figure 3 – LX2208 Evaluation Board Layout
Copyright © 2007
Rev. 1.0a, 2007-06-05
Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 8
LX2208
EVALUATION BOARD USER GUIDE
LX2208 EVALUATION BOARD BILL OF MATERIALS
MISCELLANEOUS COMPONENTS
Line
Item
Part Description
1
2
3
4
5
6
Microsemi IC – Tri Level Li-Ion Charger
LED - Amber
LED - Red
LED - Green
Thermistor – NTC, 100k
Terminal Block 2 position/ 7mm spacing
7
Header 3 pin 0.100in spacing
8
9
10
11
Header 2 pin 0.100in spacing
Header 1 pin
Jumper, 2 Pos, 0.100 inch spacing
Printed Circuit Board
Manufacturer & Part #
MICROSEMI
Panasonic
Panasonic
Panasonic
Vishay
OST
Microsemi
LX2208ILD
LNJ414K8YRA
LNJ214K8ARA
LNJ314G8TRA
NTHS0402N01N1003J
OST/2/7.0
Case
3x3 MLP
0603
0603
0603
0402
Reference
Designators
U1
CHARGING
FULL
POWER ATTACH
RT1
BATTERY
I PGM, SHUTDN,
PWR SEL
BAT TEMP
PWR, GND
I PGM, SHUTDN
SGE#3547 X1
Qty
1
1
1
1
1
1
3
1
2
2
1
CAPACITORS
Line
Item
1
2
Part Description
Capacitor, X5R, 10uF, 10V, 10%
Capacitor, X7R, 0.47uF, 16V, 20%
Part Number
Case
Reference
Designators
Qty
Taiyo Yuden LMK316BJ106KD-T
Taiyo Yuden EMK212BJ474KD-T
1206
0805
C1,2
C3
2
1
Case
Reference
Designators
Qty
0805
0805
0805
0805
0805
0805
R1,2,11,12
R3,6,7
R4
R5
R8
R10
4
3
1
1
1
1
RESISTORS
Line
Item
1
2
3
4
5
6
Part Description
Resistor, 1.00K, 1%, 1/10W
Resistor, 2.49K, 1%, 1/10W
Resistor, 15.8K, 1%, 1/10W
Resistor, 3.57k, 1%, 1/10W
Resistor, 121K, 1%, 1/10W
Resistor, 24.9K, 1%, 1/10W
Copyright © 2007
Rev. 1.0a, 2007-06-05
Part Number
Panasonic
Panasonic
Panasonic
Panasonic
Panasonic
Panasonic
ERJ-6ENF1001V
ERJ-6ENF2491V
ERJ-6ENF1582V
ERJ-6ENF3571V
ERJ-6ENF1213V
ERJ-6ENF2492V
Microsemi
Analog Mixed Signal Group
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 9