DC1855A - Demo Manual

DEMO MANUAL DC1855A
LT3030
Dual 750mA/250mA
Low Dropout, Low Noise,
Micropower Linear Regulator
Description
Demonstration circuit 1855A is a dual, micropower, low
noise and low dropout voltage linear regulator featuring
the LT3030. The input voltages are independent for each
channel of DC1855A and can range from 2.2V to 20V.
Each channel has a jumper that sets the output voltage to
either 1.5V, 1.8V, 2.5V, 3.3V, 5V or a voltage that is user
programmed by the installation of a resistor. For channel 1
and channel 2, the maximum output currents are 750mA
and 250mA and the ceramic output capacitors are 22µF
and 10µF respectively. The internal reference of each
channel is bypassed with a 10nF capacitor for reduced
output noise. Each channel has a jumper for shutdown
and a terminal for PWRGD that is pulled up to the input
supply. A resistor divider can be easily added that allows
precise lockout at low input voltages.
Performance Summary
PARAMETER
CONDITIONS
Minimum Input Voltage, VIN
VOUT = 1.8V
The LT3030 is well suited to applications that require
sequencing between dual regulator channels, particularly microprocessor systems and instrumentation that
require low noise. Systems with batteries will benefit
from the low dropout of the LT3030 and its micropower
operation. DC1855A features the LT3030 in a 28-lead
4mm × 5mm QFN package. The LT3030 data sheet must
be read in conjunction with this demo manual to properly
use or modify demo circuit DC1855A.
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.
Specifications are at TA = 25°C
MIN
TYP
MAX
2.2
20
Maximum Input Voltage, VIN
UNITS
V
V
Output Voltage, VOUT
VOUT SELECT = 1.5V
VOUT SELECT = 1.8V
VOUT SELECT = 2.5V
VOUT SELECT = 3.3V
VOUT SELECT = 5V
1.48
1.77
2.45
3.21
4.86
Maximum Channel 1 Output Current, IOUT1
VIN1 = 3.3V, VOUT1 =1.8V
750
mA
Maximum Channel 2 Output Current, IOUT2
VIN2 = 3.3V, VOUT2 =1.8V
250
mA
1.53
1.83
2.56
3.37
5.12
V
V
V
V
V
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DEMO MANUAL DC1855A
Quick Start Procedure
It is easy to set up demonstration circuit DC1855A to
evaluate the performance of the LT3030. Refer to Figure 1
for the proper measurement equipment setup and follow
the procedure below:
high above the output may increase power dissipation to
an unacceptable level. Finally, a protection feature within
the LT3030 reduces output current capability at higher
input voltages.
1.With the input supplies and loads off and turned down,
make all connections according to Figure 1. Set the
output voltages for channels 1 and 2 with the VOUT
SELECT jumpers. Make sure the VOUTEN jumpers are
in the ON positions.
3.Increase the loads to the desire output current. Verify
that the output voltages are as programmed by the
VOUT SELECT jumpers.
2.Turn on the input supplies and increase them to the
desired input voltages.
NOTE WHEN SETTING THE INPUT VOLTAGE: An input
voltage that is too close to the programmed output voltage (too low) may cause dropout operation and a loss
of output voltage regulation. An input voltage that is too
2
NOTE: If an output voltage is low, temporarily disconnect
the load to make sure that it is not set too high.
4.Once the proper output voltages are established, adjust
the input voltage and load within the operating ranges
and observe the output voltage regulation, low quiescent
current, shutdown and PWRGD operation and other
parameters.
dc1855af
DEMO MANUAL DC1855A
Quick Start Procedure
LOAD
–
+
+
–
–
–
+
+
+
–
–
+
–
+
+
–
dc1855 F01
+
–
+
–
LOAD
Figure 1: Proper Measurement Equipment Setup for DC1855A
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3
DEMO MANUAL DC1855A
Parts List
ITEM
QTY
REFERENCE
PART DESCRIPTION
MANUFACTURER/PART NUMBER
Required Circuit Components
1
2
C1, C2
CAP, X7R, 1µF, 25V, 20%, 0805
TDK C2012X7R1E105M
2
1
C3
CAP, X5R, 22µF, 6.3V, 20%, 0805
TAIYO YUDEN, JMK212ABJ226M
3
1
C4
CAP, X5R, 10µF, 6.3V, 20%, 0805
AVX, 08056D106MAT
4
2
R5, R6
RES., CHIP., 237K, 1%, 1/16W, 0603
VISHAY, CRCW0603237KFKEA
5
1
R8
RES., CHIP., 54.9K, 1%, 1/16W, 0603
VISHAY, CRCW060354K9FKEA
6
1
R9
RES., CHIP., 113K, 1%, 1/16W, 0603
VISHAY, CRCW0603113KFKEA
7
1
U1
IC., LT3030EUFD, QFN28EUFD-4 × 5
LINEAR, LT3030EUFD
CAP, X7R, 0.01µF, 25V, 10%, 0603
AVX, 06033C103KAT2A
Optional Demo Board Circuit Components
1
0
C5, C6
2
0
C7, C8
CAP, OPT, TANT, 4.7µF, 50V, 10%, 7343
3
0
C9, C10
CAP., OPT, 7343
4
0
R1, R2, R3, R4
RES., 1M, 5%, 1/16W, 0603
VISHAY, CRCW06031M00JNEA
5
0
R7
RES., CHIP., 54.9k, 1%, 1/16W, 0603
VISHAY, CRCW060354K9FKEA
6
0
R10
RES., CHIP., 113k, 1%, 1/16W, 0603
VISHAY, CRCW0603113KFKEA
7
0
R11, R12
RES., CHIP., 249k, 1%, 1/16W, 0603
VISHAY, CRCW0603249KFKEA
8
0
R13, R14
RES., CHIP., 402k, 1%, 1/16W, 0603
VISHAY, CRCW0603402KFKEA
9
0
R15, R16
RES., CHIP., 732k, 1%, 1/16W, 0603
VISHAY, CRCW0603732KFKEA
10
0
R17, R18, R19, R20
RES., OPT, 0603
Hardware: For Demo Board Only
1
10
E1-E10
TESTPOINT, TURRET, .095"
MILL-MAX, 2501-2-00-80-00-00-07-0
2
2
JP1, JP2
3 PIN, 0.079 SINGLE ROW HEADER
SAMTEC, TMM103-02-L-S
3
2
JP3, JP4
2 × 6, 0.079 DOUBLE ROW HEADER
SAMTEC, TMM106-02-L-D
4
4
XJP1-XJP4
SHUNT, .079" CENTER
SAMTEC, 2SN-BK-G
4
dc1855af
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.
GND
VOUT1
750mA
PWRGD1
E4
E3
E9
+
R7
54.9k
C3
22uF
6.3V
0805
R9
113k
R11
249k
5%
R1
1M
R13
402k
R15
732k
R5
237k
R17
OPT
JP3
VOUT1 SELECT
* SEE PERFORMANCE SUMMARY
FOR MINIMUM INPUT VOLTAGE
CONDITIONS.
C9
OPT
7343
R3
1M
5%
R19
OPT
JP1
VOUT1EN
C5
0.01uF
19
24
25
26
3
4
27
22
28
1
2
23
GND
GND
GND
GND
GND
GND
ADJ1
PWRGD1
BYP1
OUT1
OUT1
SHDN1
U1
LT3030EUFD
ON
1
2
3
OFF
E2
C1
1uF
25V
0805
21
IN1
20
IN1
GND
C7
4.7uF
50V
OPT
7343
1.5V
1.8V
2.5V
3.3V
5V
OPT
1
3
5
7
9
11
2
4
6
8
10
12
+
R20
OPT
JP2
VOUT2EN
GND
GND
GND
GND
GND
GND
ADJ2
PWRGD2
BYP2
OUT2
OUT2
SHDN2
14
18
13
12
11
6
5
10
15
9
7
8
ON
3
2
1
OFF
E1
IN2
16
IN2
17
GND
29
R6
237k
R4
1M
5%
R12
249k
R14
402k
R16
732k
R18
OPT
+
+
C10
OPT
7343
E6
E5
E10
E8
GND
VOUT2
250mA
PWRGD2
* VIN2
C8
2.2V - 20V
4.7uF
50V
OPT
7343 E7
GND
1. ALL RESISTORS ARE IN OHMS 1% 0603.
2. ALL CAPACITORS ARE IN MICROFARADS 0603.
R10
113k
C4
10uF
6.3V
0805
C2
1uF
25V
0805
NOTE: UNLESS OTHERWISE SPECIFIED
R8
54.9k
JP4
C6
0.01uF VOUT2 SELECT
5%
R2
1M
1.5V
1.8V
2.5V
3.3V
5V
OPT
2
4
6
8
10
12
1
3
5
7
9
11
* VIN1
2.2V - 20V
DEMO MANUAL DC1855A
Schematic Diagram
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DEMO MANUAL DC1855A
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
6
dc1855af
Linear Technology Corporation
LT 0213 • PRINTED IN USA
1630 McCarthy Blvd., Milpitas, CA 95035-7417
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●
FAX: (408) 434-0507 ● www.linear.com
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