Linear Technology DC2118A Quick setup guide

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dc2118af
DEMO MANUAL DC2118A
DESCRIPTION
LTC4040
Battery Charger and Backup
Power Manager
Demonstration circuit 2118A is a combination step-down
battery charger and step-up battery backup regulator us-
ing the LT C
®
4040 monolithic system power manager. The
DC2118A has an input voltage range from 4.8V to 5.5V
with overvoltage protection (OVP) to 40V, as limited by
the external MOSFET. The input current is monitored to
prioritize the load up to the 2.5A threshold before charge
current is reduced.
Battery Charging
As initially configured, DC2118A is programmed for 2A
charge current limit when in charge mode. The charge
voltage is jumper-selectable in 8 discrete steps from
3.45V to 3.6V for LiFePO4chemistry or 3.95V to 4.1V for
Li-ion chemistry, according to the F2/F1/F0 programming
input settings.
The charge current limit is adjustable via the PROG pin
resistor. End-of-charge status is triggered by current
falling below C/8 and indicated by the CHRG LED. The
optional NTC input provides temperature fault detection
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.
PERFORMANCE SUMMARY
and status indicated by the FAULT LED. Charging can be
enabled/disabled with the ENCHG jumper.
Battery Backup
Following an input power failure, the circuit automatically
shifts to battery backup boost mode to regulate the VSYS
output rail. The backup mode system output voltage is
initially programmed for 5V. The input power failure status
is indicated by the PFO LED.
If VSYS ever falls below the programmed reset threshold
voltage, the RST LED will change states to indicate the
need to reset the system and recharge the battery. Backup
regulationcanbeenabled/disabledwiththeENBSTjumper.
For convenience, all LEDs can be disabled with the LED
jumper to reduce the quiescent current of the system.
Design files for this circuit board are available at
http://www.linear.com/demo/DC2118A
Specifications are at TA= 25°C
PARAMETER CONDITIONS VALUE
Charge Mode
Input Voltage Range 4.8V to 5.5V
Overvoltage Protection Range Limited by Q1 BVDSS 5.5V to 40V
Input Current Limit R7 = 10mΩ 2.5A
Default Charging Voltage F2 = 1 (Li-Ion), F1 = 1, F0 = 1 4.10V
Charging Current RPROG = 1.00k 2.0A
Safety Timer Period F2 = 1 (Li-Ion) 4Hr
F2 = 0 (LiFePO4) 2Hr
Backup Mode
DCIN Input Power Fail Threshold R2 = 357k, R27 = 121k, DCIN Falling 4.8V
System Output Voltage R4 = 1.69M, R5 = 324k 5.0V
Backup Battery Voltage Range 2.7V to 5.0V
System Reset Threshold R4 = 1.69M, R5 = 324k, VSYS Falling 4.6V
Backup Boost Efficiency VBAT = 3.6V, ISYS = 2A, VOUT = 5V 89%
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dc2118af
DEMO MANUAL DC2118A
QUICK START PROCEDURE
Demonstration circuit 2118A is easy to set up to evaluate
the performance of LTC4040. Refer to Figure 2 for proper
measurement equipment setup and follow the procedure
below.
1. The jumpers are set as below for a typical 4.1V charg-
ing application:
JP1 NTC INT
JP2 ENCHG ON
JP3 ENBST ON
JP4 F1 1
JP5 F0 1
JP6 LEDS ON
JP7 F2 1
2. With all power off, connect the input supply, system
load, and meters as shown in Figure 3.
Charge Mode
3. Connect the battery as shown in Figure 3 to charge at
4.1V, 2A. For alternate charge voltage settings, refer
to Table 1.
4. Turn on the input power supply to evaluate charge
mode. Adjust the input voltage and current limit to
the desired value.
NOTE: While DC2118A is robust to overvoltage condi-
tions up to 40V on DCIN, DO NOT exceed this limit or
damage may occur to MOSFET Q1 and IC U1.
5. Turn on and adjust the system load as necessary.
Charging current will be limited when input current
exceeds 2.5A.
6. The CHRG LED will toggle off when the charge current
has dropped below 250mA. The timer will continue to
run and charging will continue until the timer period
ends. Multiple timer periods may be necessary to fully
charge a large capacity battery, such as the one used
to obtain Figure 1.
7. If the battery voltage does not increase above the low
battery threshold during the precondition time or the
thermistor value exceeds the normal range, CHRG will
toggle off and FAULT will toggle on indicating a bad
battery.
Backup Mode
8. Turn off the input power supply to evaluate backup
mode.
9. The PFO LED will toggle on indicating input power
failure.
10. Adjust the system load as necessary.
Figure 1. Typical Battery Charge Cycle Figure 2. Typical Battery Discharge Cycle
PERFORMANCE SUMMARY
TIME (Hrs)
0
I
BAT
(A)
2.25
2.00
1.50
1.00
0.50
1.75
1.25
0.75
0.25
0
V
BAT
+ V
CHRG
(V)
4.2
4.0
3.6
3.2
2.8
3.8
3.4
3.0
2.6
2.4
5 93 7
dc2118 F01
104 82 61
9600mAh Li-Ion
VIN = 5V
RPROG = 1.00k
TIMER
RESTART
TIMER
START
CHRG
VBAT
IBAT
C/8
TERMINATION
TIME (Hrs)
0:00
V
BAT
(V)
5
4
2
3
1
0
I
BAT
(A)
5
4
2
3
1
0
1:30
dc2118a F02
2:302:001:000:30
9600mAh Li-Ion
VSYS = 5V
ISYS = 2A
POWER
FAIL
BACKUP
STARTED
VSYS
IBAT VBAT
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dc2118af
DEMO MANUAL DC2118A
QUICK START PROCEDURE
Figure 3. Proper Measurement Equipment Setup
11. Total backup runtime is based on battery capacity,
circuit efficiency, and system load. Figure 2 shows an
example dischargecurve with constant current system
load.
12. WhenVSYS falls below 7.5% of the programmed value,
or 4.6V, then RST will toggle on.
Optional
1. UseanexternalthermistorconnectedbetweenEXTNTC
and GND as shown in Figure 3, with the NTC jumper,
JP1, set to EXT.
2. Change the setting of the ENCHG, JP2, or ENBST, JP3,
jumpers to enable/disable charging and backup boost
respectively.
3. Monitor the PROG pin voltage for a scaled representa-
tion of the instantaneous charge current according to
the relationship:
IBAT =
2000 • V
PROG
RPROG
Where RPROG = R6 = 1kΩ.
4. MonitortheCLPROGpinvoltage forascaledrepresenta-
tion of the instantaneous total input current according
to the relationship:
IVIN =
V
CLPROG
32 •R
S
Where RS= R7 = 10mΩ.
5. All status LEDs can be disconnected to reduce the
quiescent current by setting the LEDS jumper, JP6 to
OFF.
6. External VDD can be used by connecting to EXTVDD
and installing 0Ω for R16.
+
+
–
+
Table 1. Battery Charge Voltage Jumper Settings
JP7 JP5 JP4
F2 = 1 (Li-Ion) F2 = 0 (LiFePO4) F1 F0
3.95 3.45 0 0
4.00 3.50 0 1
4.05 3.55 1 0
4.10 3.60 1 1
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dc2118af
DEMO MANUAL DC2118A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 1 CIN1 CAP., X7R, 0.1µF, 10%, 50V, 0805 AVX, 08055C104KAT4A
2 2 COUT1, COUT2 CAP., X5R, 100µF, 20%, 10V, 1210 MURATA, GRM32ER61A107ME20L
3 1 C2 CAP., X7R, 2.2µF, 10%, 6.3V, 0805 MURATA, GRM21BR70J225MA01L
4 1 C3 CAP., X5R, 10µF, 20%, 10V, 0603 AVX, 0603ZD106MAT2A
5 2 C7, C9 CAP., X7R, 0.1µF, 10%, 10V, 0603 AVX, 0603ZC104KA72
6 1 L1 INDUCTOR, 2.2µH COILCRAFT, XAL5030-222ME
7 1 Q2 XSTR, MOSFET N-CHANNEL, 20-V VISHAY, SiS424DN-T1-GE3
8 1 R2 RES., 357k, 1/16W, 1%, 0402 VISHAY, CRCW0402357KFKED
9 1 R4 RES., 1.69MΩ, 1/16W, 1%, 0402 VISHAY, CRCW04021M69FKED
10 1 R5 RES., 324k, 1/16W, 1%, 0402 VISHAY, CRCW0402324KFKED
11 1 R6 RES., 1.00k, 1/10W, 1%, 0603 VISHAY, CRCW06031K00FKED
12 1 R7 RES., 0.01Ω, 1/4W, 1%, 1206 VISHAY, WSL1206R0100FEB
13 1 R8 RES., 10k, 1/16W, 1%, 0402 VISHAY, CRCW040210K0FKED
14 1 R11 RES., 0Ω JUMPER, 0402 VISHAY, CRCW04020000Z0ED
15 1 R25 RES., 1Ω, 1/8W, 5%, 0805 VISHAY, CRCW0805100RJNEA
16 1 R27 RES., 121k, 1/16W, 1%, 0402 VISHAY, CRCW040260K4FKED
17 1 U1 I.C., LTC4040EUFD LINEAR TECH, LTC4040EUFD#PBF
Additional Demo Board Circuit Components
1 0 C4, C6 CAP., 0402 OPT
2 1 C5 CAP., X5R, 0.1µF, 10%, 10V, 0402 MURATA, GRM155R71A104KA01J
3 1 D1 DIODE, SCHOTTKY NXP, BAT46WJ
4 1 D3 DIODE, LED, SMT, RED, 0603 LITE-ON, LTST-C193KRKT-5A
5 2 D4, D5 DIODE, LED, SMT, ORANGE, 0603 LTIE-ON, LTST-C193KFKT-5A
6 1 D6 DIODE, LED, SMT, GREEN, 0603 LITE-ON, LTST-C193KGKT-5A
7 1 Q1 XSTR, MOSFET N-CHANNEL, 40-V VISHAY, SiS488DN-T1-GE3
8 1 RNTC RES., 10k, 1/16W, 1%, 0402 VISHAY, CRCW040210K0FKED
9 1 R1 RES., 6.2k, 1/8W, 5%, 0805 VISHAY, CRCW08056K20JNEA
10 0 R12, R13, R16 RES., 0402 OPT
11 4 R21-R24 RES., 390Ω, 1/16W, 5%, 0402 VISHAY, CRCW0402390RJNED
Hardware: For Demo Board Only
1 18 E1, E2, E4-E19 TEST POINT, TURRET, 0.094" MILL-MAX, 2501-2-00-80-00-00-07-0
2 7 JP1-JP7 3 PIN JUMPER, 2mm SAMTEC TMM-103-02-L-S
3 7 XJP1-XJP7 SHUNT, 2mm SAMTEC 2SN-BK-G
4 4 STAND-OFF STAND-OFF, NYLON KEYSTONE, 8834(SNAP ON)
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dc2118af
DEMO MANUAL DC2118A
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 representa-
tion that the interconnection of its circuits as described herein will not infringe on existing patent rights.
SCHEMATIC DIAGRAM
5 5
4 4
3 3
2 2
1 1
D D C C B B A A
VSYS GND
VBAT GND
GND DCIN
EXTNTC
4.8V - 5.5V
BSTOFF
CHGOFF
F2=1(LI-ION) F2=0(LIFEP04) F1 F0
3.95V 3.45V 0 0 4.00V 3.50V 0 1 4.05V 3.55V 1 0 4.10V 3.60V 1 1
3.
FAULT
PFO RST
CHRG
CLPROG
NOTES: UNLESS OTHERWISE SPECIFIED, 1. ALL RESISTORS ARE 0402, 1%.
EXTVDD
2. ALL CAPACITORS ARE 0603, X7R.
OV PROTECTION
GND
GND
5V IN BACKUP
2A CHARGE
4. LIMITED BY Q1 VDS RATING.
SEE NOTE 4
PROG
(DEFAULT)
VIN
VIN
VSYS
VDD
VDD VDD VDD VDD
VSYS
VDD
VDD
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
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. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
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4
Thursday, April 30, 2015
11
BATTERY CHARGER
N/A
LTC4040EUFD24
DEMO CIRCUIT 2118A
BACKUP POWER MANAGER
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
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. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
4
Thursday, April 30, 2015
11
BATTERY CHARGER
N/A
LTC4040EUFD24
DEMO CIRCUIT 2118A
BACKUP POWER MANAGER
SIZE DATE:
IC NO. REV.
SHEET OF
TITLE:
APPROVALS
PCB DES.
APP ENG.
TECHNOLOGY Fax: [phone]
Milpitas, CA 95035 Phone: [phone] McCarthy Blvd. LTC Confidential-For Customer Use Only
CUSTOMER NOTICE
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. THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND
SCHEMATIC
SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.
SCALE = NONE
www.linear.com
4
Thursday, April 30, 2015
11
BATTERY CHARGER
N/A
LTC4040EUFD24
DEMO CIRCUIT 2118A
BACKUP POWER MANAGER
C7 0.1uF
0603
Q2
SiS424DN
3 1 2
4
5 6 7 8
R22 390 5%
C9
0.1uF
10V
D5 ORG
JP6
ON OFF
LEDS
1 3 2
R6
1.00k 0603
1%
L1
2.2uH
COILCRAFT
XAL5030-222ME
COUT1
100uF
10V 1210
E2
R13 OPT
R4 1.69M
E6
SEE NOTE 3
E17
R1 6.2k 0805
R24 390 5%
C2
2.2uF 6.3V
0805
JP4
1 0
F0
1 3 2
E7
R27
121k 1%
C3
10uF, 10V
0603
E11
E18
U1
LTC4040EUFD
FAULT
9
VIN 6
F1
13
F0
14
F2
12
PFI
19
BSTFB 18
SW 22 SW 21
2
PROG
CLPROG
3
VSYS 1
VSYS 24
BAT 23
CHGOFF
4
BSTOFF
5
RST
11
CLN 7
RSTFB 10
OVSNS 16
NTC 17
CHRG
8
IGATE 15
PFO
20
25
GND
C4
OPT
E12
E8
R2
357k 1%
R16
OPT
JP1
INT EXT
NTC
1
3
2
COUT2
100uF
10V 1210
JP2
OFF
ON
ENCHG
1 3 2
JP3
OFF
ON
ENBST
1 3 2
RNTC
10k
E13 E15
R21 390 5% R12
OPT
R5 324k
R23 390 5%
E14
D3 RED
C5
0.1uF
R8
10k
CIN1 0.1uF 50V 0805
C6
OPT
D1 BAT46WJ
E16
D4 ORG
R7
0.01 1%
1206
D6 GRN
E9
JP7
1 0
F2
1 3 2
E19
R25 1 5% 0805
E10
E5
JP5
1
0
F1
1 3 2
E4
Q1 SiS488DN
3 1 2
4
5 6 7 8
E1
R11
0
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dc2118af
DEMO MANUAL DC2118A
Linear Technology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
 LINEAR TECHNOLOGY CORPORATION 2015
LT 0615 • PRINTED IN USA
DEMONSTRATION BOARD IMPORTANT NOTICE
Linear Technology Corporation (LT C ) 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 LT C 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 LT C 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. LT C assumes no liability for applications assistance,
customer product design, software performance, or infringement of patents or any other intellectual property rights of any kind.
LT C 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 LT C applica-
tion engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
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