Linear Technology LTC3624, DC2359A Demo Manual

DEMO MANUAL DC2359A

LTC3624

High Efficiency Synchronous

Step-Down Regulator with

Description

Demonstration circuit 2359A is a synchronous step-down

®

regulator using LT C The DC2359A operates from an input voltage range of 2.7V to 17V and provides and adjustable output voltage range from 1.2V to 5V (V current. A user-selectable mode input is provided with the following options: Burst Mode the highest efficiency at light loads, while Pulse-Skipping mode (PS) provides the lowest output voltage ripples. Forced Continuous mode (FC) is also available for low EMI and noise interference.

The MODE/SYNC pin can also be used to synchronize the switching frequency to an external clock signal. The switching frequency is fixed at 1MHz with a ±40% sync capture range.

The regulator features ultralow quiescent current and high efficiencies over a wide V

3624HMSE monolithic buck regulator.

< VIN) at 2A of continuous output

OUT

®

operation provides

and V

IN

range. DC2359A

OUT

Ultralow Quiescent Current

uses very low profile surface mount components and all ceramic output capacitor solutions. The compact 12-lead MSE (5mm × 4mm × 1mm) thermally enhanced package makes LTC3624HMSE an excellent choice for battery powered equipment, emergency radio and general pur pose step specified over an of –40°C to 150°C, typically required for automotive, in dustrial and military applications that are subject to high ambient temperatures.

It is recommended to read the data sheet and demo manual of LTC3624 prior using or making any changes to DC2359A.

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.

-down power supplies. The H-Grade version is operating junction temperature range

linear.com/demo/DC2359A

-

performance summary

PARAMETER CONDITIONS VALUE

Input Voltage Range 2.7V to 17V

On Board User Selectable Output Voltages V

Default Mode Setting JP2 Burst Mode (“BM” on Circuit Board)

Fixed Switching Frequency Internally Programmed Frequency 1MHz ±20%

Default Output Voltage V

Maximum Continuous Output Current I

Output Voltage Ripples (Peak to Peak) V

Load Transient Response V

Thermal Performance V

Efficiency V

OUT

Specifications are at TA = 25°C

= 2.7V to 17V, I

IN

(V

< VIN)

OUT

VIN = 12V, V

= 12V, V

IN

= 12V, V

IN

C

OUT

= 12V, V

IN

f

SW

= 12V, V

IN

f

SW

OUT

= 1 × 47µF

OUT

= 1MHz, TA = 25°C

OUT

= 1MHz, TA = 25°C

OUT

= 5V, I

= 2A

= 0A to 2A 5V ±2%

OUT

= 2A 8.8mV (Figure 7)

OUT

= 1A to 2A,

OUT_STEP

= 2A,

OUT

= 2A, BM,

OUT

1.2V, 1.8V, 2.5V, 3.3V and 5V

2A

219mV (Figure 8)

Figure 9

89.7% (Figure 3)

dc2359afb

1

DEMO MANUAL DC2359A

Quick start proceDure

Demonstration circuit 2359A is easy to set up to evaluate the performance of the LTC3624HMSE. Please refer to Figure 1 for proper measurement equipment setup and follow the procedure below:

1. Place jumpers in the following positions for a typical 5V output application:

Table 1. Typical 5V Output Voltage Jumper Selection

JP1 JP2 JP7

RUN MODE/SYNC V

ON BM 5.0V

OUT

2. With power off, connect the input power supply at

(E1) and GND (E2)

V

IN

3. Connect the Load between V

(E8) and GND (E9).

OUT

Preset the load to 0A.

4. Connect the DMMs to the input and output to monitor the input voltage and output voltage.

5. Turn on the power supply at the input. The RUN pin jumper should be at “ON” position. Measure and make sure the input supply voltage is 12V. The output voltage should be 5V ±2%.

7. To select other output voltages, use the on board user selectable output voltage jumpers. Shutting down LTC3624HMSE by placing RUN pin jumper (JP1) to the OFF position or turn off the input power supply. Refer to the following table (Table 2) for the output voltage selection and repeat step 2 to 6.

Table 2. Output Voltage Jumper Selection

JP3 JP4 JP5 JP6 JP7 JP8*

1.2V 1.8V 2.5V 3.3V 5V User Select

*If JP8 is selected, R6 needs to be calculated and inserted to obtain the desired output voltage.

NOTE 1: To measure the input/output voltage ripple properly, do not use the long ground lead on the oscilloscope probe. See Figure

2 for the proper scope probe technique. Short, stiff leads need to be soldered to the (+) and (–) terminals of an output capacitor. The probe’s ground ring needs to touch the (–) lead and the probe tip needs to touch the (+) lead.

NOTE 2: The DC2359A can also be used to evaluate the LTC3624HMSE-2 (2.25MHz) by simply replacing U1 with the LTC3624HMSE-2 and changing inductor L1 to 1.5µH (Coilcraft XAL4020-152ME).

6. Once the input and output voltages are properly es tablished, adjust the loads within the operating range (0Ato 2A Max) and observe the output voltage regulation, output other parameters. Refer

voltage ripple, switch node waveform and

to Figure 2 for proper output

voltage ripple measurement.

-

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2

Quick start proceDure

DEMO MANUAL DC2359A

Figure 1. Proper Measurement Equipment Setup

+ –

Figure 2. Scope Probe Placement for Measuring Output Voltage Ripple

C

OUT

V

OUT

GND

dc2359afb

3

DEMO MANUAL DC2359A

EFFICIENCY (%)

1.10

DC2359a F03

100

EFFICIENCY (%)

100

DC2359a F04

EFFICIENCY (%)

100

DC2359a F06

1.10

EFFICIENCY (%)

DC2359a F05

100

Quick start proceDure

95

90

85

80

75

70

65

60

55

50

0.01

0.10 1.00

LOAD CURRENT (A)

1.2V

1.8V

2.5V

3.3V

5.0V

OUT OUT OUT OUT OUT

Figure 3. Burst Mode – Efficiency vs Load Current at 12V

95

90

85

80

75

70

65

60

55

50

0.01 0.10 1.00 LOAD CURRENT (A)

1.2V

1.8V

2.5V

3.3V

OUT OUT OUT OUT

95

90

85

80

75

70

65

60

55

50

0.0

IN

Figure 4. Forced Continuous Mode –

1.0 1.5

LOAD CURRENT (A)

Efficiency vs Load Current at 12V

95

90

85

80

75

70

65

60

55

50

0.0

1.0 1.5

LOAD CURRENT (A)

1.2V

1.8V

2.5V

3.3V

5.0V

1.2V

1.8V

2.5V

3.3V

OUT OUT OUT OUT OUT

2.00.5

IN

OUT OUT OUT OUT

2.00.5

Figure 5. Burst Mode – Efficiency vs Load Current at 5V

4

IN

Figure 6. Forced Continuous Mode – Efficiency vs Load Current at 5V

IN

dc2359afb

Quick start proceDure

DC2359a F07

20mV/DIV

V

OUT

VSW

10V/DIV

DEMO MANUAL DC2359A

20MHz BW LIMIT

= 8.8mV

V

P-P

= 1MHz

f

SW

= 12V

V

IN

= 5V

V

OUT

= 2A

I

LOAD

L = 3.3µH

= 1x 47µF/6.3V/X5R/1206

C

OUT

t(1µs/DIV)

Figure 7. Measured Output Voltage Ripple

dc2359afb

5

DEMO MANUAL DC2359A

200mV/DIV

CFF = 15pF

DC2359a F08

Quick start proceDure

V

OUT

20MHz BW LIMIT

V

= 219mV

P-P

I

OUT

1A/DIV

= 1MHz

f

SW

= 12V

V

IN

= 5V

V

OUT

= 1A TO 2A

I

LOAD

L = 3.3µH

= 1x 47µF/6.3V/X5R/1206

C

OUT

1A TO 2A

t(50µs/DIV)

Figure 8. Load Transient Response

6

dc2359afb

Quick start proceDure

A

DEMO MANUAL DC2359A

VIN = 12V

= 5V

V

OUT

= 2A

I

LOAD

L = 3.3µH

= 1MHz

f

SW

NO FORCED AIRFLOW T

= 25°C

DC2359a F09

Figure 9. Thermal Performance

dc2359afb

7

DEMO MANUAL DC2359A

parts List

ITEM QTY REFERENCE PART DESCRIPTION MANUFACTURER/PART NUMBER

Required Circuit Components

1 1 CFF CAP, 0402 15pF 1% 50V NPO AVX 04025U150FAT2A

2 1 CIN CAP, 47μF 20% 20V 33mΩ PANASONIC OSCON 20SVPA47M

3 2 C2, C3 CAP, 1206 22μF 10% 25V X5R MURATA GRM31CR61E226KE15L

4 1 C4 CAP, 1206 47μF 20% 6.3V X5R TAIYO YUDEN JMK316BJ476ML-T

5 1 C8 CAP, 0603 2.2μF 10% 10V X5R AVX 0603ZD225KAT2A

6 1 L1 IND, 3.3μH XAL4030-332ME

7 2 R1, RSET RES, 0402 619kΩ 1% 1/16W VISHAY CRCW0402619KFKED

8 1 R2 RES, 0402 309kΩ 1% 1/16W VISHAY CRCW0402309KFKED

9 1 R3 RES, 0402 196kΩ 1% 1/16W VISHAY CRCW0402196KFKEA

10 1 R4 RES, 0402 137kΩ 1% 1/16W VISHAY CRCW0402137KFKED

11 1 R5 RES, 0402 84.5kΩ 1% 1/16W VISHAY CRCW040284K5FKED

12 2 R7, R12 RES, 0402 0Ω JUMPER VISHAY CRCW04020000Z0ED

13 1 R11 RES, 0402 1MΩ 5% 1/16W VISHAY CRCW04021M00JNED

14 1 U1 IC, MONOLITHIC SYNCHRONOUS BUCK

Additional Demo Board Circuit Components

1 0 C5 CAP, 1206 22μF 20% 6.3V X5R OPTION TAIYO YUDEN EMK316BJ226ML-T OPTION

2 0 C6 CAP, 1210 OPTION OPTION

3 0 C7 CAP, 0402 OPTION OPTION

4 0 R6, R8, R9, R10 RES, 0402 OPTION OPTION

Hardware

1 10 E1, E2, E3, E4, E5, E6, E7, E8,

2 1 JP1 HEADER, 3-PIN, 2mm SAMTEC TMM-103-02-L-S

3 1 JP2 HEADER, 4-PIN, 2mm SAMTEC TMM-104-02-L-S

4

5 4 MH1, MH2, MH3, MH4

6 3 XJP1, XJP2, XJP7 SHUNT, 2mm SAMTEC 2SN-BK-G

E9, E10

6 JP3, JP4, JP5, JP6, JP7, JP8 HEADER, 2-PIN, 2mm SAMTEC TMM 102-02-L-S

REGULATOR

TURRET MILL-MAX 2501-2-00-80-00-00-07-0

STANDOFF, SNAP ON KEYSTONE 8833

LINEAR TECH LTC3624HMSE#PBF

8

dc2359afb

DEMO MANUAL DC2359A

5

4

3

2

1

11

schematic Diagram

1

ADJ

2A

VOUT

E8

C6

OPT

OPTC51206

47uFC46.3V

R12

0

L1

3.3uH

1210

1206

CFF

RSET

619k

E9

15pF

1%

Coilcraft XAL4030-332ME

2

SW1SW

U1

8

GND

FB

E10

R6

R5

R4

R3

R2

R1

GND

OPT

84.5K

1%

137k

1%

196k

309k

1%

619k

1%

JP8

USER SELECT

JP7

5.0V

JP6

3.3V

JP5

2.5V

JP4

1.8V

JP3

1.2V

VOUT

6

PGOOD

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

SCHEMATIC

MONOLITHIC SYNCHRONOUS BUCK REGULATOR

TITLE:

` \

Z _

APPROVALS

PCB DES.

APP ENG.

7

NC

GND

12

GND

11

1

SHEET OF

1

LTC3624HMSE

DEMO CIRCUIT 2359A

LTC3624HMSE

DEMO CIRCUIT 2359A

LTC3624HMSE

DEMO CIRCUIT 2359A

2

IC NO. REV.

Wednesday, August 12, 2015

WITH ULTRA-LOW QUIESCENT CURRENT

N/A

SIZE

DATE:

SIZE

DATE:

SIZE

DATE:

SCALE = NONE

3

VIN

LTC3624HMSE (1MHz)

VIN

3

4

22uFC325V

22uFC225V

R7

1206

0

RUN

132

ON

5

RUN

OFF

C7

R8

OPT

JP1

[1]

CIN

20V

47uF

+

GND

E7

RUN

E1

VIN

E2

2.7V - 17V

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.

INTVCC9MODE/SYNC

10

C8

2.2uF

10V

0603

[2]

R9

OPT

132

MODE

BM

[2]

INTVCC

E3

INTVCC

FCM / SYNC

C C

R10

4

OPT

PS

[2]

JP2

E4

SYNC

INTVCC

E5

GND

R11

1Meg

E6

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

LINEAR TECHNOLOGY HAS MADE A BEST EFFORT TO DESIGN A

CIN IS AN OPTIONAL CAPACITOR. IT IS INSERTED

ON THE DC2359A TO DAMPEN THE (POSSIBLE)

RINGING VOLTAGE DUE TO THE LONG INPUT LEADS.

ON A NORMAL, TYPICAL PCB, WITH SHORT TRACES,

THE CAPACITOR IS NOT NEEDED.

FOR FCM OPERATION, STUFF R9 AND

R10 WITH 1MEG OHM RESISTOR.

[1]

NOTES:

PGOOD

B B

[2]

PERFORMANCE OR RELIABILITY. CONTACT LINEAR

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

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

A A

TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.

THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND

TECHNOLOGY APPLICATIONS ENGINEERING FOR ASSISTANCE.

SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.

THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND

SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.

THIS CIRCUIT IS PROPRIETARY TO LINEAR TECHNOLOGY AND

SUPPLIED FOR USE WITH LINEAR TECHNOLOGY PARTS.

4

5

dc2359afb

9

DEMO MANUAL DC2359A

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

Linear Technology Corporation

10

1630 McCarthy Blvd., Milpitas, CA 95035-7417

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

dc2359afb

LT 1015 REV B • PRINTED IN USA