Linear Technology DC2169A Demo Manual

Description

DEMO MANUAL DC2169A

LT8616

Dual 42V Synchronous Monolithic Step-Down

Regulator with 6.5µA Quiescent Current

Demonstration circuit 2169A is a dual monolithic step-down

®

DC/DC switching regulator featuring the LT

8616. The

LT8616 is a high efficiency, high speed, dual synchronous monolithic step-down switching regulator that consumes only 6.5μA of quiescent current with both channels enabled. The demo circuit is designed for 5V, 1.5A and 3.3V, 2.5A outputs. Both channels contain all switches and neces

sary circuitry to minimize the external components and solution size. Fast minimum ON time of 35ns enables high

to low V

V

IN

conversion at high switching frequency.

OUT

Independent input voltage, feedback, soft-start and power good pins for each channel simplify complex power supply tracking/sequencing requirements.

The inputs of the two channels are connected on the demo board by default. They can also be separated by removing the 0Ω resistor (R13) from the board. Each output can be independently disabled using its own EN/UV pin, while

must be connected to 3.4V or above even if only

V

IN1

channel 2 is in installed between V inputs should be tied to V

use. The demo board has an EMI filter

IN2

and V

. To use the EMI filter, the

EMI

.

EMI

The switching frequency of both channels can be programmed either

via an oscillator resistor or a common

external clock up to 3MHz.The SYNC pin on the demo

®

board is grounded by default for Burst Mode

operation.

To synchronize to an external clock, move JP1 to SYNC/ MODE and apply the external clock to the SYNC/MODE turret. The R

resistor (R5) should be chosen to set the

T

LT8616 internal switching frequency at least 20% below the lowest synchronization input.

Low ripple Burst Mode operation increases the efficiency at the light load while keeping the output ripple low.

2

Figure 1 and Figure

show the demo board efficiency for

each channel at 12V input voltage in Burst Mode opera-

3

tion. Figure

shows the temperature rising on DC2169A demo board with different input voltages under full load conditions on both channels.

The LT8616 data sheet gives a complete description of the part, operation and application information. The data sheet must be read in conjunction with this demo manual for DC2169A. The LT8616 is assembled in a 28-lead plastic TSSOP package. Proper board layout is essential for both low EMI operation and maximum thermal performance. See the data sheet sections for details.

Design files for this circuit board are available at

http://www.

L, LT, LTC, LTM, Linear Technology, the Linear logo and Burst Mode are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners.

linear.com/demo/DC2169A

performance summary

SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS

V

IN1

V

IN2

V

OUT1

V

OUT2

f

SW

I

OUT1

I

OUT2

EFE Efficiency at DC V

Channel 1 Input Supply Range 5.8 42 V

Channel 2 Input Supply Range 4.1 42 V

Channel 1 Output Voltage 4.88 5.02 5.15 V

Channel 2 Output Voltage 3.21 3.29 3.37 V

Switching Frequency RT = 14.7kΩ 1.85 2.05 2.25 MHz

Channel 1 Max Output Current 1.5 A

Channel 2 Max Output Current 2.5 A

IN1

= V

Specifications are at TA = 25°C

= 12V, I

IN2

OUT1

= 1.5A, I

OUT2

= 2.5A 85.1 %

dc2169af

1

DEMO MANUAL DC2169A

performance summary

100

90

80

70

EFFICIENCY (%)

60

50

0.6

LOAD CURRENT (A)

fSW = 2MHz

= 12V

V

IN1

= 5V

V

OUT1

DC2169A F01

1.50.30 0.9 1.2

Figure 1. LT8616 Channel 1 Efficiency vs Load Current

100

90

80

70

EFFICIENCY (%)

60

50

1

LOAD CURRENT (A)

fSW = 2MHz

= 12V

V

IN2

= 3.3V

V

OUT2

DC2169A F02

2.50.50 1.5 2

Figure 2. LT8616 Channel 2 Efficiency vs Load Current

Figure 3. LT8616 Temperature Rising vs Input Voltage

2

100

fSW = 2.05MHz

= 5V, I

V

OUT1

80

60

40

TEMPERATURE RISING (°C)

20

OUT1

INPUT VOLTAGE (V)

= 1.5A

24

40168 32

DC2169A F03

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Quick start proceDure

DEMO MANUAL DC2169A

DC2169A is easy to set up to evaluate the performance of the LT8616. Refer to Figure 4 for proper measurement equipment setup 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 V or V

and GND terminals. See Figure 5 for the proper

OUT

IN

scope technique.

1. Place JP1 on the Burst Mode position.

2. With power off, connect the input power supply to V

EMI

and GND. Make sure that the input voltage does not exceed 42V.

3. With power off, connect loads from V to GND.

V

OUT2

to GND, and

OUT1

4. Turn on the power at the input.

5. Check for the proper output voltages (5V and 3.3V).

NOTE: If there is no output, temporarily disconnect the

load to make sure that the load is not set too high or is shorted.

6. Once the proper output voltages are established, adjust the load within the operating ranges and observe the output voltage regulation, ripple voltage, efficiency and other parameters.

7. An external clock can be added

SYNC function is used (JP1 on the SYNC/MODE

when

to the SYNC terminal

position). Please make sure that the SYNC frequency is at least 20% higher than the set switching frequency. See the data sheet section Synchronization.

Figure 4. Proper Measurement Equipment Setup

V

OUT

Figure 5. Measuring Input or Output Ripple

GND

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3

DEMO MANUAL DC2169A

parts List

ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER

Required Circuit Components

1 2 C2, C3 CAP., X7R, 0.1µF, 10V, 10% 0402 SAMSUNG, CL05B104KP5NNNC

2 1 C4 CAP., X7R, 22µF, 10V, 10% 1210 MURATA, GRM32ER71A226KE20L

3 1 C5 CAP., X7R, 47µF, 10V, 10% 1210 MURATA, GRM32ER71A476KE15L

4 2 C6, C7 CAP., X7R, 0.01µF, 10V, 10% 0603 AVX, 0603ZC103K AT2A

5 2 C8, C9 CAP., C0G, 4.7pF, 50V, ±0.25pF 0603 AVX, 06035A4R7CAT2A

6 2 C10, C11 CAP., X7R, 2.2µF, 50V, 10% 1206 MURATA, GRM31CR71H225KA88L

7 5 C12, C17, C19, C27, C28 CAP., X7R, 1µF, 10V, 10% 0603 AVX, 0603ZC105KAT2A

8 4 C13, C14, C15, C16 CAP., X7R, 0.1µF, 50V, 10% 0402 TDK, C1005X7R1H104K050BB

9 1 L1 IND., 3.3µH, XAL4030 COILCRAFT, XAL4030-332ME

10 1 L2 IND., 2.2µH, XFL4020 COILCRAFT, XFL4020-222ME

11 6 R1, R3, R6, R8, R10, R11 RES., CHIP, 1M, 0.1W, 1%, 0603 VISHAY, CRCW06031M00FKEA

12 1 R2 RES., CHIP, 187k, 0.1W, 1%, 0603 VISHAY, CRCW0603187KFKEA

13 1 R4 RES., CHIP, 316k, 0.1W, 1%, 0603 VISHAY, CRCW0603316KFKEA

14 1 R5 RES., CHIP, 14.7k, 0.1W, 1%, 0603 VISHAY, CRCW060314K7FKEA

15 2 R7, R13 RES., CHIP, 0Ω, 0.1W, 0603 VISHAY, CRCW06030000Z0EA

16 1 U1 IC., LT8616EFE TSSOP-28/EB LINEAR TECH., LT8616EFE#PBF

Additional Demo Board Circuit Components

1 2 C1, C18

2

3 1 L4 IND., 0.22µH, IHLP1212AB VISHAY, IHLP1212ABERR22M11

4 1 C23 CAP., X7R, 4.7µF, 50V, 10% 1206 SAMSUNG, CL31B475KBHNNNE

5 1 C24 CAP., X7R, 10µF, 50V, 10% 1210 MURATA, GRM32ER71H106KA12L

6 2 C25, C26 CAP., X7R, 0.1µF, 50V, 10% 0402 TDK, C1005X7R1H104K050BB

7 0 R9, R12 (OPT) RES., CHIP, 0603

Hardware: For Demo Board Only

1 16 E1-E16 TESTPOINT, TURRET, .094" PBF MILL-MAX, 2501-2-00-80-00-00-07-0

2 1 JP1 4 PIN 0.079 SINGLE ROW HEADER SULLINS, NRPN041PAEN-RC

3 1 XJP1 SHUNT, .079" CENTER SAMTEC, 2SN-BK-G

1 L3 CHIP BEAD, 30Ω, MPZ2012 TDK, MPZ2012S300AT

CAP., ALUM., 22µF, 63V, SUN ELECTRONIC INDUSTRIES CORP., 63CE22BS

4

dc2169af

DEMO MANUAL DC2169A

5

4

3

2

1

schematic Diagram

1

4

1

www.linear.com

VIN2

4.1V - 42V

E10

R8

C11

C18

1M

22uF

+

50V

2.2uF

63V

63CE22BS

R9

OPT

1206

GND

E11

EN2

E13

0

R7

C3 0.1uF

L2

10V

2.2uH

XFL4020-222ME

0402

VOUT2

4.7pF

C9

3.3V / 2.5A

GND

E4

1uF

C19

1uF

C27

C5

47uF

10V

1210

1M

R3

R4

316K

PG2

PG1

E6

E12

E14

VOUT2

VOUT1

R10

1M

R6

1M

www.linear.com

Fax: (408)434-0507

Milpitas, CA 95035

Phone: (408)432-1900

1630 McCarthy Blvd.

LTC Confidential-For Customer Use Only

Fax: (408)434-0507

Milpitas, CA 95035

Phone: (408)432-1900

1630 McCarthy Blvd.

LTC Confidential-For Customer Use Only

Fax: (408)434-0507

Milpitas, CA 95035

Phone: (408)432-1900

1630 McCarthy Blvd.

LTC Confidential-For Customer Use Only

TECHNOLOGY

DUAL 42V SYNCHRONOUS MONOLITHIC

IC NO. REV.

SCHEMATIC

STEP-DOWN REGULATOR WITH 6.5µA QUIESCENT CURRENT

SIZE

TITLE:

SHEET OF

1

LT8616EFE

DEMO CIRCUIT 2169A

Monday, January 19, 2015

N/A

DATE:

2

0

R13

VIN1 VIN2

VIN1

C16

0.1uF

C14

0.1uF

C13

0.1uF

C15

0.1uF

C10

2.2uF

50V

R11

C1

22uF

+

E1

PAD150-094

5.8V - 42V

50V

1206

1M

63V

0402

63CE22BS

GND

25

24

23

18

19

20

U1

E2

22

1

NC

VIN2

ENUV2

NC

VIN1

NC

EN/UV1

16

LT8616EFE

C2

R12

OPT

E15

EN1

BIAS

BOOST1

8

0402

10V

6

BOOST2

SW1

9

10

0.1uF

L1

SW1

3.3uH

1M

R1

VOUT1

26

3

5

FB2

SW2

SW24SW2

FB1

14

13

XAL4030-332ME

C8

4.7pF

C4

22uF

10V

1uF

C28

VOUT1

1uF

C17

E3

GND

5V / 1.5A

27

FB2

TR/SS112TR/SS2

28

C7

0.01uF

R2

187k

1210

E5

2

C6

E9

SS1/TR1

11

PG1

PG2

17

0.01uF

SYNC

E8

SS2/TR2

INTVCC

21

NC

7

GND

29

RT

15

R5

SYNC/MODE

132

PULSE SKIPPING

E7

SYNC/MODE

C12

1uF

14.7k

2MHz

4

JP1

SYNC/MODE

BURST MODE

L4

4 Pins 2mm Ctrs.

L3

VIN2

0.22uH

IHLP1212ABERR22M11

C24

50V

10uF

1210

30 ohm

MPZ2012S300AT

50V

C23

4.7uF

1206

50V

C26

0.1uF

0402

50V

C25

0.1uF

0402

E16

VEMI

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

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

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

SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.

TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.

THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND

SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.

TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.

THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND

SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.

3

4

5

1. ALL RESISTORS ARE IN 0603

ALL CAPACITORS ARE IN 0603

NOTE: UNLESS OTHERWISE SPECIFIED

D D

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.

C C

B B

A A

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5

DEMO MANUAL DC2169A

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 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 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.

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 LTC application engineer.

Mailing Address:

Linear Technology

1630 McCarthy Blvd.

Milpitas, CA 95035

Linear Technology Corporation

6

1630 McCarthy Blvd., Milpitas, CA 95035-7417

(408) 432-1900 ● FAX: (408) 434-0507 ● www.linear.com

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LT 0515 • PRINTED IN USA

 LINEAR TECHNOLOGY CORPORATION 2015