Linear Technology DC2049A Demo Manual

DESCRIPTION

DEMO MANUAL DC2049A

LT3999EMSE

Low Noise Isolated

Power Supply

The DC2049A demonstrates how a power supply regulates

®

two output voltage by using the LT

3999 and low dropout

(LDO) regulators.

The LT3999 is a monolithic push-pull DC/DC driver which
features wide input range and small external passive
components.

The LT3999 has duty circle control for ΔV

compensa-

IN

tion, which allows for a wide input voltage range and low
LDO losses.

DC2049A employs a push-pull topology that inherently

The
provides a low-noise solution. The design is well suited
to noise sensitive systems such as medical instruments,
industrial sensing and control, data conversion and wide
band communications. The post regulator LDOs reduce
output noise further. For more details about the LDOs,
please check the LT3065 and LT3090 data sheets.

PERFORMANCE SUMMARY

Specifications are at TA = 25°C

The DC2049A produces an isolated 12V

and –12V

OUT

OUT

at
up to 200mA each from a 10V ~ 15.5V input voltage range.
This board can be modified, by changing the transformer
(and duty cycle), to produce other output voltages.

The DC2049A features a small transformer, small inductors
and capacitors that work at a 1MHz switching frequency.

The LT3999 data sheet gives a complete description of the
part, operation and applications information. The data sheet
must be read in conjunction with this demo manual. The
LT3999EMSE is assembled in a 10-lead plastic MSE pack

-

age with a thermally enhanced ground pad. Proper board

is essential for maximum thermal performance. See

layout
the data sheet section Layout Consideration Check List.

Design files for this circuit board are available at

http://www.linear.com/demo/DC2049A

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.

PARAMETERS MIN TYP MAX UNITS

Input Voltage Range 10.0 15.5 VDC

Output Voltage 1 (VOUT1) 11.64 12.0 12.3 VDC

Output Voltage 2 (VOUT2) –12.36 –12.0 –11.64 VDC

Output Current 1 0 200 mA

Output Current 2 0 200 mA

Switching Frequency 1.0 MHz

Isolation 1000 VDC

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DEMO MANUAL DC2049A

QUICK START PROCEDURE

DC2049A is easy to set up to evaluate the performance of
the LT3999EMSE. Refer to Figure 1 for proper measure­ment equipment setup and follow the procedure below:

Connect Load 1 (positive) between the VOUT1 and GND

1.
terminals and another Load 2 (negative) between the
VOUT2 and GND terminals.

2. With power off, connect the input power supply to the
+VIN and –VIN terminals.

3. Turn the input power supply on and make sure the
voltage is between 10V and 15.5V.

4. To measure the output noise, connect one end of a BNC
connector J1. Connect the other end of the BNC cable
to an oscilloscope with a 50Ω input impedance. Refer
to Application Note 70 for more precise techniques for
measuring the output noise.

*J1 is the BNC connector to coaxial
cable for noise measurement, please
refer to AN70 Appendix B for details.

Figure 1. Test Procedure Setup Drawing for DC2049A

2

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QUICK START PROCEDURE

EFFICIENCY (%)

70

POWER LOSS (W)

4

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DEMO MANUAL DC2049A

POWER LOSS

60

EFFICIENCY

50

40

I

= 200mA

OUT1

= 200mA

I

OUT2

30

10

12 14

VIN (V)

3

2

1

0

1611 13 15

Figure 2. Efficiency and Power Loss vs Input Voltage with LT3999 and LDOs

Figure 3. Switch Node Voltage, VIN = 10V

Figure 5. Thermal Image, VIN = 10V, I

OUT1

= I

OUT2

= 200mA

Figure 4. Switch Node Voltage, VIN = 15V

Figure 6. Thermal Image, VIN = 15V, I

OUT1

= I

OUT2

= 200mA

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DEMO MANUAL DC2049A

PARTS LIST

ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER

Required Circuit Components

1 1 U1 I.C., Push-Pull DC/DC Driver Linear Tech. Corp. LT3999EMSE#PBF

2 1 U2 I.C., Low Noise Linear Reg. Linear Tech. Corp. LT3065EDD#PBF

3 1 U3 I.C., Negative Linear Reg. Linear Tech. Corp. LT3090EDD#PBF

4 4 D1, D2, D3, D4 Schottky Diode 200V/1AMP Central Semi. CMSH1-200HE

5 1 T1 Xfmr. Würth Elektronik 750314781

6 2 L1, L2 Inductor, 39µH Coilcraft XFL3012-393MEC

7 1 C1 Cap., Alum 10µF 50V 10% Sun Elect., 50CE10BSS

8 1 C2 Cap., X5R 4.7µF 25V 20% 0805 Taiyo Yuden TMK212BJ475MG-T

9 2 C3 Cap., X7R 0.1µF 25V 10% 0603 AVX 06033C104KAT 2A

10 1 C4 Cap., NPO 180pF 50V 10% 0805 AVX 08055A181K AT2A

11 1 C5 Cap., X7R 4.7µF 25V 20% 1206 TDK C3216X7R1E475M

12 2 C7, C14 Cap., X5R 10µF 50V 20% 1206 TDK C3216X5R1H106M

13 1 C9 Cap., X7R 0.01µF 50V 10% 0603 AVX 06035C103K AT2A

14 2 C10, C16 Cap., X7R 10µF 25V 20% 1206 TDK C3216X7R1E106MT

15 1 C17 Cap., X7R 2200pF 1KV 20% 1206 AVX 1206AC222M AT2A

16 3 R1, R2, R13 Res., Chip 1.00M 0.10W 1% 0603 Vishay CRCW06031M00FKEA

17 1 R4 Res., Chip 143

18

19 1 R7 Res., Chip 12.1k 0.10W 1% 0603 Vishay CRCW060312K1FKEA

20 1 R8 Res., Chip 13.3k 0.10W 1% 0603 Vishay CRCW060313K3FKEA

21 1 R9 Res., Chip 49.9k 0.10W 1% 0603 Vishay CRCW060349K9FKEA

22 1 R10 Res., Chip 39Ω 0.125W 5% 0805 Vishay CRCW080539R0JNEA

23 1 R12 Res., Chip 10k 0.50W 5% 1210 Vishay CRCW121010K0JNEA

24 1 R14 Res., Chip 52.3k 0.10W 1% 0603 Vishay CRCW060352K3FKEA

25 1 R16 Res., Chip 10k 0.25W 5% 1206 Vishay CRCW120610K0JNEA

26 1 R17 Res., Chip 243k 0.10W 1% 0603 Vishay CRCW0603243KFKEA

Additional Demo Board Circuit Components

1 1 R11 Res/Jumper, Chip 0Ω 0.10W 0603 Vishay CRCW06030000Z0EA

2 2 C12 Cap., X7R 0.1µF 25V 10% 0603 AVX 06033C104KAT 2A

3 1 C11 Cap., X5R 1µF 25V 20% 0603 AVX 06033D105M AT2A

4 0 C6, C8, C13, C15 (Opt) Cap., 1206

5 0 R3, R6 (Opt) Res., 0603

6 0 R15 (Opt) Res., 1206

Hardware: For Demo Board Only

1 1 J1 BNC Connector Connex 112404

2 7 E1, E2, E3, E4, E5, E6, E7 Turret, Testpoint Mill Max 2501-2-00-80-00-00-07-0

1 R5 Res., Chip 86.6k 0.10W 1% 0603 Vishay CRCW060386K6FKEA

k 0.10W 1% 0603 Vishay CRCW0603143KFKEA

4

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SCHEMATIC DIAGRAM

DEMO MANUAL DC2049A

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.

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DEMO MANUAL DC2049A

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. 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.

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 applica­tion engineer.

Mailing Address:

Linear Technology

1630 McCarthy Blvd.

Milpitas, CA 95035

Copyright © 2004, Linear Technology Corporation

Linear Technology Corporation

6

1630 McCarthy Blvd., Milpitas, CA 95035-7417

[phone] ● FAX: [phone] ● www.linear.com

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LT 1014 • PRINTED IN USA

 LINEAR TECHNOLOGY CORPORATION 2014