Linear Technology DC1920A Quick setup guide

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DEMO MANUAL DC1920A
DESCRIPTION
LTC3553EUD-2
Micropower USB Power Manager with
Li-Ion Charger, Always-On LDO and Buck Regulator
Demonstration circuit DC1920A is a micropower USB
power manager with Li-ion charger, buck DC/DC, and
always-on LDO regulator featuring the LTC
®
3553EUD-2. 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
QUICK START PROCEDURE
Design files for this circuit board are available at
http://www.linear.com/demo
(TA= 25°C)
SYMBOL PARAMETER CONDITIONS MIN MAX UNITS
VBUS Bus Input Voltage Range 4.35 5.5 V
V(BAT) Battery Float Voltage Constant Voltage Mode 4.15 4.23 V
I(BAT) Battery Charge Current Constant Current Mode, RPROG = 1.87k 380 420 mA
VLDO LDO Output Voltage I(VLDO) ≤ 150mA 3.25 3.35 V
VBUCK Buck Regulator Output Voltage I(VBUCK) ≤ 200mA 1.15 1.25 V
Refer to Figure 1 for the proper measurement equipment
setup and jumper settings and follow the procedure below.
NOTE: When measuring the input or output voltage ripple,
care must be taken to avoid a long ground lead on the
oscilloscope probe. Measure the input or output voltage
ripple by touching the probe tip directly across the VBUS
or VOUT(x) and GND terminals. See Figure 2 for proper
scope probe technique.
1. Set PS1 = 0V, PS2 = 3.6V. Application of power to BAT
(PS2), causes a POR. As shown in Figure 5 of the data
sheet, the POR causes the LTC3553EUD-2 to enter the
PDN1 state. In the PDN1 state VLDO is on, and VBUCK
is off. After 1s, the LTC355EUD-2 transitions to the Hard
Reset (HR) state. In HR VLDO is off, and total current
draw from the battery is less than 1µA.
2. Press “REGS ON” button for > 0.5 seconds. Observe
I(BAT) (AM2), VBUCK (VM5) and VLDO (VM6). Press-
ing the “REGS ON” button for > 0.5 seconds causes
the LTC3553EUD-2 to enter the PUP1 state. In the
PUP1 state both regulators are on. After 5 seconds,
the LTC3553EUD-2 enters the PON state. Observe
VLDO (VM6). VLDO is always-on, and is 3.3V. The
LTC3553EUD-2 is in standby mode which reduces
the battery current to less than 15µA, even with both
regulators running. In standby mode the maximum
current from the buck regulator is reduced to 10mA.
Since BUCK_ON (pin 7) on the LTC3553EUD-2 is pulled
up by the buck output, the buck regulator will remain
on, and at 1.2V.
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DEMO MANUAL DC1920A
QUICK START PROCEDURE
3. Set STBY (JP6) to “OFF”, and observe I(BAT) (AM2)
and VPROG (VM2). The LTC3553EUD-2 is now oper-
ating in normal mode drawing more current from the
battery. However the buck regulator is now capable of
delivering up to 200mA, VLDO can deliver 150mA in
either standby or normal mode.
4. Set PS1 to 5V. Observe I(VBUS) (AM1), I(BAT) (AM2)
and VPROG (VM2). Since VBUS is now available, the
battery charger is operating, but chargecurrent is limited
by the input current limit to 100mA (max.).
5. Set HPWR (JP2) to “500mA”. Observe I(VBUS) (AM1),
I(BAT) (AM2) and VPROG (VM2). The input current limit
is now 500mA (max.) so the battery charger is deliver-
ing the full programmed charge current of ~400mA to
the battery.
6. Set LD2 to 200mA, LD3 to 150mA. Observe VBUCK
(VM5), VLDO (VM6) and I(BAT) (AM2). The buck
regulator is supplying 200mA, and the always-on LDO
is supplying 150mA. At ~90% efficiency the buck
regulator is drawing ~50mA and the LDO is drawing
150mA from the VBUS supply. So, the battery charger
is delivering approximately 250mA. This is because the
input current limit is 450mA – 150mA – 50mA = 250mA.
7. Set LD2 to 0A, LD3 to 0A and PS1 to 0V. Press “Buck
OFF” button. Observe VBUCK (VM5) and VLDO (VM6).
The buck regulator is now off. To turn off the LDO hold
down the ON button for at least 14 seconds. This puts
the LTC3553EUD-2 in “Hard Reset” and shuts off the
LDO.
8. Reset the Jumpers to their default position.
Note: All connections from equipment should be Kelvin
connected directly to the board pins which they are con-
nected on this diagram (Figure 1) and any input or output
leads should be twisted pair.
LTC3553 Product Options (for Reference only)
Part Number LDO PGOOD Hard Reset Time
LTC3553 On/Off Control No 5 Seconds
LTC3553-2 Always On Yes 14 Seconds
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DEMO MANUAL DC1920A
QUICK START PROCEDURE
Figure 1. Proper Measurement Equipment Setup for DC1920A
Figure 2. Measuring Input or Output Ripple
–
+
+–
VM2
VM3
AM2
3.6
+
_
VM4
+
_
VM6
+
_
VM5
+–
AM1
+
_
VM1
+–
PS1
1A
4.35V - 5.5V SUPPLY
+
–PS2
1A
0V - 5V SUPPLY
+
–
AM3
+–
LD2
2A
0V - 5V
+
–
AM4
+–
LD3
2A
0V - 5V
+
–
V
IN
GND
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DEMO MANUAL DC1920A
PARTS LIST
ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER
Required Circuit Components
1 3 C2, C7, C10 CAP, CHIP, X5R, 10F, ±20%, 6.3V, 0603 TDK, C1608X5R0J106K
2 1 C4 CAP, CHIP, X5R, 4.7F, ±20%, 4V, 0402 MURATA, GRM155R60G475M
3 1 C5 CAP, CHIP, X5R, 1F, ±10%, 10V, 0402 MURATA, GRM155R61A105KE15D
4 1 C6 CAP, CHIP, C0G, 10pF, ±5%, 50V, 0402 MURATA, GRM1555C1H100JZ01D
5 1 C9 CAP, CHIP, X5R, 2.2F, ±20%, 6.3V, 0402 MURATA, GRM155R60J225ME15D
6 1 L1 IND, SMT, 10H, 459m, ±20%, 0.631A, 2mm ×2mm COILCRAFT, EPL2014-103MLC
7 1 R3 RES, CHIP, 1.87k, ±1%, 1/16W, 0402 VISHAY, CRCW04021K87FKED
8 2 R7, R11 RES, CHIP, 100k, ±1%, 1/16W, 0402 VISHAY, CRCW0402100KFKED
9 3 R8, R10, R17 RES, CHIP, 0 JUMPER, 1/16W, 0402 VISHAY, CRCW04020000Z0ED
10 2 R11, R14 RES, CHIP, 649k, ±1%, 1/16W, 0402 VISHAY, CRCW0402649KFKED
11 1 R12 RES, CHIP, 2.05M, ±1%, 1/16W, 0402 VISHAY, CRCW04022M05FKED
12 1 R15 RES, CHIP, 332k, ±1%, 1/16W, 0402 VISHAY, CRCW0402332KFKED
13 1 U1 MICROPOWER USB POWER MANAGER WITH LI-ION
CHARGER, LDO AND BUCK REGULATOR
LINEAR TECH., LTC3553EUD-2
Additional Demo Board Circuit Components
1 1 C1 CAP, CHIP, X5R, 10F, ±20%, 6.3V, 0603 TDK, C1608X5R0J106K
2 0 C3-OPT CAP, CHIP, C0G, 1pF, ±5%, 50V, 0402 VISHAY, VJ0402A1R0JXAA
3 1 C8 CAP, CHIP, X5R, 100F, ±20%, 6.3V, 1206 MURATA, GRM31CR60J107ME39L
4 1 D1 LED, GREEN, 0603 LITE-ON, LTST-C190KGKT
5 4 R1, R19-R21 RES, CHIP, 1, ±5%, 1/16W, 0402 VISHAY, CRCW04021R00JNED
6 3 R2, R18, R23 RES, CHIP, 100k, ±5%, 1/16W, 0402 VISHAY, CRCW0402100KJNED
7 1 R4 RES, CHIP, 10k, ±5%, 1/16W, 0402 VISHAY, CRCW040210K0JNED
8 1 R5 RES, CHIP, 510k, ±5%, 1/16W, 0402 VISHAY, CRCW0402510KJNED
9 0 R6 RES, CHIP, 1M, ±5%, 1/16W, 0402 VISHAY, CRCW04021M00JNED
10 2 R13, R16 RES, CHIP, 20, ±5%, 1/16W, 0402 VISHAY, CRCW040220R0JNED
11 1 R22 RES, CHIP, 1k, ±5%, 1/10W, 0603 VISHAY, CRCW06031K00JNED
Hardware For Demo Board Only
1 11 E1-E2, E7-E11,
E13-E14, E16-E17
TURRET, 0.09 DIA MILL-MAX, 2501-2-00-80-00-00-07-0
2 6 E3-E6, E12, E15 TURRET, 0.061” MILL-MAX, 2308-2-00-80-00-00-07-0
3 1 J1 CONN, USB MINI-B TYCO, 1734035-2
4 0 J2-OPT CONN, 3 PIN POLARIZED HIROSE, DF3-3P-2DSA
5 7 JP1-JP7 HEADER, 3 PIN, 2mm SAMTEC, TMM-103-02-L-S
6 7 JP1-JP7 SHUNT, 2mm SAMTEC, 2SN-BK-G
7 2 PB1, PB2 SWITCH, N.O. MOMENTARY, 3.5mm × 6mm SMT PANASONIC, EVQPPFA25
8 4 STAND-OFF, NYLON, 0.375” KEYSTONE, 8832
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DEMO MANUAL DC1920A
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
4 4
3 3
2 2
1 1
4 4 3 3 22 1 1
500mA
STBY
ON
150mA
ON
HPWR
OPT
OFF
3.3V
OFF
INT
NTC
100mA
EXT
SUSP
200mA
1.2V
VOUT
PBSTAT
VBUCK
REGSON
VBUCK OFF
VFLOAT = 4.2V
BUCK_ON
OPEN
VBUCK
OPT
500mA
VOUT
PGOOD
VLDO
UNLESS NOTED: RESISTORS: OHMS, 0402, 1%, 1/16W
CAPACITORS: uF, 0402, 10%, 50V
GEORGE B.PRODUCTION FAB
-109-15-11
REVISION HISTORY
ETADNOITPIRCSED APPROVEDECO REV
1
DC1920A
11
MICROPOWER USB POWER MANAGER
N/A
LTC3553EUD-2
NC
GEORGEB.
09-15-11
WITH LI-ION CHARGER, LDO AND BUCK REGULATOR
SIZE DATE:
.VER.ONCI
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 TODESIGNA
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
VOUT
VBUS
VBUS
VBUCK VOUT
VBUS
VOUT
VLDO
VBUCK
VBUCK
VOUT
VOUT
VLDO
E5
PROG
JP6
E15 CHRG
C2
10uF
0603 6.3V E17 VOUT
2.9V - 5.5V
0.5A
R8 0
PB2
R11 649k
C5
1uF 10V
J1
USB MINI-B
1
2
3 4
5
VBUS
D-
D+
ID
GND
C4
4.7uF
4V
JP3
R17 0
R14
649k
R5 510k
5%
R21 1.0 5%
E14 BAT
E9 VINLDO
100uF 6.3V
1206
C8 20%
E10GND
U1
LTC3553EUD-2
1
5
3
10
4
9
2
7
11 12 13 14
15 16
21
8
6
17 18
19
20
HPWR
GND
PBSTAT
LDO
ON
LDO_FB
PGOOD
BUCK_ON
VINLDO
BVIN
SW
CHRG
NTC PROG
GND
BUCK_FB
STBY
BAT
VOUT
SUSP
VBUS
TP1 D-
R16
20
5%
E8 VLDO
L1
10uH
EPL2014-103MLC
C10 10uF 0603 6.3V
R18 100K
5%
R3
1.87k
R19
1.0
5%
E1
4.35V - 5.5V
VBUS
C6
10pF 5%
JP5
TP5
R6
1M OPT
5%
R1
1.0
5%
R15 332k
C1
10uF 0603
6.3V
E7 GND
R23 100K
5%
R2
100k
5%
JP7
D1 CHRG
E6
BUCK_ON
E11 VBUCK
E2
GND
E13GND
C3 1pF 5%
R9
100k
E16GND
E12PGOOD
TP4
C9 2.2uF
6.3V 0402 20%
TP2 D+
R7
100k
JP1
R4
10k
5%
R12
2.05M
JP4
R13
20 5%
R10
0
PB1
TP3 ID
R22
1K 5%
E4
ON
J2
DF3-3P-2DSA
1 2 3BAT
GND ENTC
JP2
R20 1.0
5%
C7
10uF
0603 6.3V
E3
PBSTAT
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DEMO MANUAL DC1920A
LinearTechnology Corporation
1630 McCarthy Blvd., Milpitas, CA 95035-7417
[phone] ●FAX: [phone] ●www.linear.com
© LINEAR TECHNOLOGY CORPORATION 2012
LT 0112 • PRINTED IN USA
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 applica-
tion engineer.
Mailing Address:
Linear Technology
1630 McCarthy Blvd.
Milpitas, CA 95035
Copyright © 2004, Linear Technology Corporation
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