DC1229B - Demo Manual

DEMO MANUAL DC1229B
LT3650EDD-4.2/LT3650EDD-4.1
2A Monolithic Li-Ion
Battery Chargers
Description
DC1229B is a 2A monolithic Li-Ion battery charger featuring the LT®3650EDD-4.2/LT3650EDD-4.1. The LT3650 is a
complete mid-power Li-Ion battery charger that can operate
over a wide input voltage range. The circuit provides CC/CV
charging with a maximum charge current externally programmable up to 2A. A precondition feature trickle charges
a low-voltage battery and bad battery detection provides
PERFORMANCE SUMMARY
PARAMETER
a signal if the battery doesn’t respond to preconditioning.
The LT3650EDD is available in a 12-lead (3mm × 3mm)
DFN surface mount package with an exposed pad.
Design files for this circuit board are available at
http://www.linear.com/demo
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
(TA = 25°C)
CONDITIONS
VALUE
Input Voltage Range
7.5V to 32V
VOUT
3.7V to 4.24V
Output Float Voltage
Constant Voltage Mode
4.2V/4.1V
Output Current Limit ILIM
RRNG = 20kΩ
2A
Operating Principles
LT3650 is a complete monolithic mid-power Li-Ion battery
charger, addressing high input voltage applications with
solutions that require a minimum of external components.
The IC uses a 1MHz constant frequency, average-current
mode step-down architecture. Internal reverse voltage
protection allows direct connection to the input supply
without a blocking diode for single-cell applications
(LT3650-4.2/LT3650-4.1).
NOTE: A blocking diode on the input supply connection
is recommended to prevent the input from ringing below
ground with a battery on the output.
The LT3650 incorporates a 2A switch that is driven by a
bootstrapped supply to maximize efficiency during charging cycles. Wide input range allows operation to full charge
from 5V ±5% (single cell) to 36V. A precision-threshold
shutdown pin allows incorporation of UVLO functionality
using a simple resistor-divider. The IC can also be put into
a low-current shutdown mode, in which the input supply
bias is reduced to only 15µA.
The LT3650 incorporates several degrees of charge current
control freedom. The overall maximum charge current is
set using an external inductor current sense resistor. A
maximum charge current programming pin allows dynamic
manipulation of the battery charge current. The LT3650
also incorporates a system input-supply current limit
control feature that servos the battery charge current to
accommodate overall system load requirements.
The LT3650 automatically enters a battery precondition
mode if the sensed battery voltage is very low. In this mode,
the charging current is reduced to 15% of the programmed
maximum, as set by the inductor sense resistor, RSENSE.
Once the battery voltage climbs above an internally set
threshold of 2.9V/cell, the IC automatically increases
maximum charging current to the full programmed value.
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1
DEMO MANUAL DC1229B
Operating Principles
The LT3650 can use a charge-current based ‘C/10’ termination scheme, which ends a charge cycle when the battery
charge current falls to 1/10th the programmed maximum
charge current. The LT3650 also contains an internal charge
cycle control timer, for timer-based termination. When using
the internal timer, the IC combines C/10 detection with a
programmable time constraint, during which the charging
cycle can continue beyond the C/10 level to “top-off” a
battery. The charge cycle terminates when a specific time
elapses, typically 3 hours. When the timer-based scheme
is used, the IC also supports ‘bad-battery’ detection, which
triggers a system fault if a battery stays in precondition
mode for more than 1/8th of the total charge cycle time.
Once charging is terminated and the LT3650 is not actively
charging, the IC automatically enters a low-current standby
mode where supply bias currents are reduced to < 100µA.
If the battery voltage drops 2.5% from the full-charge float
voltage, the LT3650 engages an automatic charge cycle
restart. The IC also automatically restarts a new charge
cycle after a bad battery fault once the failed battery is
removed and replaced with another battery.
The LT3650 contains provisions for a battery temperature
monitoring circuit. This feature monitors battery temperature during the charging cycle using a thermistor,
and suspends charging and signals a fault condition if
the battery temperature moves outside a safe charging
range of 0°C to 50°C.
The LT3650 contains two digital open-collector outputs,
which provide charger status and signal fault conditions.
These binary-coded pins signal battery charging, standby
or shutdown modes, battery temperature faults, and bad
battery faults.
quick start procedure
DC1229 is easy to set up to evaluate the performance of
the LT3650EDD-4.2/LT3650EDD-4.1.
Use a blocking diode on the input supply connection, and
short twisted pair leads for the power connections. With
all loads and power supplies off, refer to Figure 1 for the
proper measurement and equipment setup.
Follow the procedure below:
1. Jumper and Power Supply Setting:
JP1 = 1
JP2 = 1
JP3 = C/10
PS1 = OFF
PS2 = OFF
2. Turn on PS2 and slowly increase the voltage until VBAT
is 2.7V while monitoring the current into the BAT pin.
If the current is less than 5mA, turn on PS1. Increase
PS1 until VIN is 5V while monitoring the input current.
If the current is less than 5mA, increase PS1 until VIN
is 12V.
3. Verify that the battery charging current, IBAT, is between
200mA and 300mA. The CHRG LED should be on and
the FAULT LED should be off.
4. Increase PS2 until VBAT is 3.6V. Verify the input current, IIN, is between 700mA and 850mA, the battery
current, IBAT, is between 1.875A and 2.225A and that
the CHRG LED is on.
5. Increase PS2 until VBAT is 4.25V. Verify the battery
charging current, IBAT, is less than 5mA and that the
CHRG LED is off.
6. Decrease PS2 until VBAT is 3.9V. Verify the battery
current, IBAT, is between 1.875A and 2.225A and that
the CHRG LED is on.
7. Decrease PS2 until VBAT is 3.6V. Connect a 10k resistor
from the RNG/SS pin to ground. Verify the charging
current, IBAT, is between 850mA and 1.0A. Verify the
voltage, VRNG, on the RNG/SS turret is between 450mV
and 550mV and the voltage VNTC on the NTC turret is
between 1.8V and 1.9V. Remove the 10k resistor from
the RNG/SS pin to ground.
8. Set JP1 to SHDN. Verify the charging current, IBAT, is
less than 5mA and that the FAULT LED and the CHRG
LED are off.
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2
DEMO MANUAL DC1229B
quick start procedure
9. Set JP1 to RUN. Connect a jumper from the NTC pin to
ground. Verify the charging current, IBAT, is less than
5mA and that the FAULT LED and the CHRG LED are on.
11.Turn on LOAD1 and set to 1A. Verify the voltage,
VSYSTEM, on the system load turret is approximately
equal to VIN.
10.Remove the jumper from NTC to ground. Verify the
charging current, IBAT, is between 1.875A and 2.225A
and that the FAULT LED is off and the CHRG LED is on.
12.Turn off PS1, PS2 and LOAD1.
Note: Put a blocking diode between the input supply and the VIN terminal.
Kelvin connect the voltage meters directly to the board terminals as shown
on the diagram. Use twisted pair input and output leads.
Figure 1. Proper Measurement Equipment Setup
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DEMO MANUAL DC1229B
parts list
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Capacitor, X7R, 1µF, 50V, 10%, 0805
Murata, GRM21BR71H105KA12B
Required Circuit Components
1
1
C1
2
2
C3, C6
Capacitor, X7R, 4.7µF, 50V, 10%, 1210
Murata, GRM32R71H475KA091B
3
1
C4
Capacitor, X7R, 10µF, 10V, 10%, 0805
Murata, GRM21BR71A106KE19B
4
2
C5, C8
Capacitor, Chip, X5R, 0.1µF, ±10%, 10V, 0402
AVX, 0402ZD104KAT2A
5
1
C7
Capacitor, X5R, 0.68µF, 10V, 10%, 0402
Murata, GRM155R61A684KE15D
6
1
C9
Capacitor, X5R, 100µF, 6.3V, 20%, 1206
Murata, GRM31CR60J107ME19L
7
1
D1
SMD, Schottky Barrier Rectifier
Central Semi, CMSH3-40MA
8
1
D2
SMD, Schottky Diode, SOT-23F
Central Semi, CMPSH1-4
9
1
L1
Power Inductor 6.8µH 20% 4.5A
Vishay, IHLP2525CZER6R8M011
10
1
R4
Resistor, Chip, 0.05Ω, 1/2W, 1%, 1206
IRC, LRC-LR1206-01-R050-F
11
1
R5
Resistor, Chip, 100k, 1/16W, 1%, 0402
Vishay, CRCW0402100KFKED
12
1
R7
Resistor, Chip, 1M, 1/16W, 1%, 0402
Vishay, CRCW04021M00FKED
13
1
R8
Resistor, Chip, 0.1Ω, 1/2W, 1%, 1206
IRC, LRC-LR1206-01-R100-F
14
1
U1 (Option A)
U1 (Option B)
2A Monolithic Li-Ion Battery Charger
Linear Technology, LT3650EDD-4.2
Linear Technology, LT3650EDD-4.1
Optional Demo Circuit Components
1
1
C2
Capacitor, SMT, 22µF, 50V, 20%
Sanyo, 50CE22BS
2
2
C10, C11
Capacitor, Chip, X7R, 0.022µF, ±10%, 16V, 0402
AVX, 0402YC223KAT2A
3
0
R6 (Opt)
Resistor, Chip, 0402
User Defined
4
1
D3
LED, Red
Panasonic, LNJ208R8ARA
5
1
D4
LED, Green
Lite-On, LTST-C190KGKT
6
1
R1
Resistor, Chip, 0 ,1/16W, 0805
Vishay, CRCW08050000Z0EA
7
2
R2, R3
Resistor, Chip, 5.1K,1/4W, 1%, 1206
Vishay, CRCW12065K10FKEA
8
0
C12 (Opt)
Capacitor, Chip, X7R, 0.01µF, ±10%, 50V, 0603
AVX, 06035C103KAT2A
1
8
E1-E8
Testpoint, Turret, .095"
Mill-Max, 2501-2-00-80-00-00-07-0
2
1
J1
Header, 3 Pins
Hirose Electric, DF3A-3P-2DSA
Hardware
3
3
JP1, JP2, JP3
2MM Single Row Header, 3 Pin
Samtec, TMM-103-02-L-S
4
3
JP1, JP2, JP3
Shunt
Samtec, 2SN-BK-G
5
4
Stand-Off, Nylon 0.375" Tall (Snap-On)
Keystone, 8832 (Snap On)
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4
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
A
B
C
D
0
1
JP2
2
4.1V
5
4.2V
LT3650EDD - 4.2
LT3650EDD - 4.1
DC1229B - B
VFLOAT *
JP1
DC1229B - A
X
0
SHDN
0
1
0
1
R2
5.1K
1206
FAULT
R7
1.0Meg
U1
+
Assembly Version
*
1
1
JP1
VERSION TABLE
UVLO
E3
C2
22uF
50V
20%
RUN
GND
7.5V - 32V
1
2
E2
1
3
VIN
1
3
JP2
2
D3
RED
4
D4
GRN
C/10
2
SW
VIN
6
7
C8
0.1uF
C5
0.1uF
8
9
10
11
CUSTOMER NOTICE
R6
(OPT)
13
TIMER GND RNG/SS
NTC
BAT
SENSE
BOOST
C6
4.7uF
50V
1210
C3
4.7uF
50V
1210
2
3
THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
R4
0.05
1206
1/4W
J.Drew
2
1/19/09
1/19/09
DATE
C4
10uF
16V
0805
10%
Wednesday, April 01, 2009
DESIGNER
ENGINEER J.Drew
APPROVED
CHECKED
DRAWN
APPROVALS
2
SCALE:
1
2
3
E5
J1
(OPT)
RNG / SS
NTC
1630 McCarthy Blvd.
Milpitas, CA 95035
Phone: (408)432-1900
Fax: (408)434-0507
E7
E6
2A
GND
DF3-3P-2DSA
BAT
GND
NTC
TECHNOLOGY
C11
0.022uF
16V
BAT
GND
VFLOAT *
E4
E8
SYSTEM LOAD
E1
1
FILENAME:
DWG NO
1
SHEET
1
OF
DC1229B - A/B
LT3650EDD - 4.2 / LT3650EDD - 4.1
2A Monolithic Li-Ion Battery Charger
SIZE CAGE CODE
TITLE
C10
0.022uF
16V
IHLP-2525CZ-01
1
L1 6.8uH
2
D1
CMSH3-40MA
CONTRACT NO.
R8
0.1
1206
1/2W
C9
100uF
6.3V
1206
20%
D2
CMPSH1-4
C1
1uF
50V
0805
LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A
CIRCUIT THAT MEETS CUSTOMER-SUPPLIED SPECIFICATIONS;
HOWEVER, IT REMAINS THE CUSTOMER'S RESPONSIBILITY TO
VERIFY PROPER AND RELIABLE OPERATION IN THE ACTUAL
APPLICATION. COMPONENT SUBSTITUTION AND PRINTED
CIRCUIT BOARD LAYOUT MAY SIGNIFICANTLY AFFECT CIRCUIT
PERFORMANCE OR RELIABILITY. CONTACT LINEAR
TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.
SHDN
LT3650EDD
12
1
FAULT
CHRG
CLP
C7
0.68uF
JP3
3
5
4
2
* U1
0805
C12
0.01uF
0603
50V
(OPT)
TIMER
Unless noted:
Resistors: Ohms
0402
1%
1/16W
Capacitors:
0402
10%
10V
R5
100K
R3
5.1K
1206
CHRG
R1 0
3
3
1
1
2
4
1
3
5
1
B
REV
A
B
C
D
DEMO MANUAL DC1229B
Schematic Diagram
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DEMO MANUAL DC1229B
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LTC) provides the enclosed product(s) under the following AS IS conditions:
This demonstration board (DEMO BOARD) kit being sold or provided by Linear Technology is intended for use for ENGINEERING DEVELOPMENT
OR EVALUATION PURPOSES ONLY and is not provided by LTC for commercial use. As such, the DEMO BOARD herein may not be complete
in terms of required design-, marketing-, and/or manufacturing-related protective considerations, including but not limited to product safety
measures typically found in finished commercial goods. As a prototype, this product does not fall within the scope of the European Union
directive on electromagnetic compatibility and therefore may or may not meet the technical requirements of the directive, or other regulations.
If this evaluation kit does not meet the specifications recited in the DEMO BOARD manual the kit may be returned within 30 days from the date
of delivery for a full refund. THE FOREGOING WARRANTY IS THE EXCLUSIVE WARRANTY MADE BY THE SELLER TO BUYER AND IS IN LIEU
OF ALL OTHER WARRANTIES, EXPRESSED, IMPLIED, OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY OR FITNESS
FOR ANY PARTICULAR PURPOSE. EXCEPT TO THE EXTENT OF THIS INDEMNITY, NEITHER PARTY SHALL BE LIABLE TO THE OTHER FOR
ANY INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES.
The user assumes all responsibility and liability for proper and safe handling of the goods. Further, the user releases LTC from all claims
arising from the handling or use of the goods. Due to the open construction of the product, it is the user’s responsibility to take any and all
appropriate precautions with regard to electrostatic discharge. Also be aware that the products herein may not be regulatory compliant or
agency certified (FCC, UL, CE, etc.).
No License is granted under any patent right or other intellectual property whatsoever. LTC assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LTC currently services a variety of customers for products around the world, and therefore this transaction is not exclusive.
Please read the DEMO BOARD manual prior to handling the product. Persons handling this product must have electronics training and
observe good laboratory practice standards. Common sense is encouraged.
This notice contains important safety information about temperatures and voltages. For further safety concerns, please contact a LTC application engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
dc1229bf
6
Linear Technology Corporation
LT 0711 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
(408) 432-1900
●
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