Datasheet UG-334 Datasheet (ANALOG DEVICES)

Evaluation Board User Guide

UG-334

10272-001

ADP1876

GND

TERMINAL

VIN
TERMINAL

GND
TERMINAL

V

OUT1

TERMINAL

V

OUT2

TERMINAL

GND
TERMINAL

One Technology Way • P. O. Box 9106 • Norwood, MA 02062-9106, U.S.A. • Tel: [phone] • Fax: [phone] • www.analog.com

Evaluation Board for the ADP1876 Step-Down DC-to-DC Controller

FEATURES

Input range: 10 V to 20 V
Two output voltages: 5 V and 1.8 V
Output current: 13 A per channel
Switching frequency: 600 kHz
Operates in PWM
Compact, low cost, and efficient design

EVALUATION BOARD DESCRIPTION

This user guide describes the design, operation, and test results
of the ADP1876-E VA L Z . The input range for this evaluation
board is 10 V to 20 V, and the two regulated output voltages are
set to 5 V (V
current. The power components, such as the MOFSETS, inductors,
and bulk input and output capacitors, were chosen to yield a low
system cost and good efficiency.

) and 1.8 V (V

OUT1

) with a maximum 13 A output

OUT2

ADP1876-EVALZ EVALUATION BOARD

ADP1876 DEVICE DESCRIPTION

The ADP1876 is a dual-channel, step-down switching controller
with integrated drivers for external N-channel synchronous power
MOSFETs. The two PWM outputs are phase shifted 180°, which
reduces the input rms ripple current, thus minimizing the required
input capacitance.

In addition, boost diodes are integrated into the ADP1876,
which lowers the overall system cost and component count. The

ADP1876 is configured to operate in forced PWM continuous

conduction mode.

The ADP1876 includes externally adjustable soft start, output
overvoltage protection, externally adjustable current limit,
power good and tracking function for Channel 1. The ADP1876
provides an output voltage accuracy of ±0.85% for a −40°C to
+85°C junction temperature and ±1.5% for a −40°C to +125°C
junction temperature. This controller can be powered from a

2.75 V to 20 V supply and is available in a 32-lead, 5 mm × 5 mm
lead frame chip scale package (LFCSP).

PLEASE SEE THE LAST PAGE FOR AN IMPORTANT
WARNING AND LEGAL TERMS AND CONDITIONS.

Figure 1.

Rev. 0 | Page 1 of 16

UG-334 Evaluation Board User Guide

TABLE OF CONTENTS

Features .............................................................................................. 1

Evaluation Board Description......................................................... 1

ADP1876 Device Description ......................................................... 1

ADP1876-EVALZ Evaluation Board .............................................. 1

Revision History ............................................................................... 2

Component Design .......................................................................... 3

Inductor Selection ........................................................................ 3

Input Capacitors ........................................................................... 3

REVISION HISTORY

11/11—Revision 0: Initial Version

Output Capacitors .........................................................................3

MOSFET Selection ........................................................................3

Test Results .........................................................................................4

Evaluation Board Operating Instructions ......................................6

Evaluation Board PCB Layout .........................................................7

Evaluation Board Schematics and Artwork ...................................8

Ordering Information .................................................................... 12

Bill of Materials ........................................................................... 12

Rev. 0 | Page 2 of 16

Evaluation Board User Guide UG-334

COMPONENT DESIGN

For information about selecting power components and
calculating component values, see the ADP1876 data sheet.

INDUCTOR SELECTION

A 1.8 µH inductor with an 18 A saturation current rating
(744325180 from Würth Elektronik) is selected. This is a
compact inductor with a ferrite core, which offers high
performance in terms of low R

and low core loss.

DC

INPUT CAPACITORS

Because of the very low ESR and high input current rating of
multilayer ceramic capacitors (MLCCs), two 10 µF MLCCs in
Size 1210 are selected as the input capacitors at the input of each
channel. In addition, a 150 µF bulk OS-CON™ (aluminum solid
capacitor with conductive polymer) capacitor from SANYO is
chosen for filtering out unwanted low frequency noise from the
input power supply.

OUTPUT CAPACITORS

A combination of POSCAP™ polymer capacitors and MLCCs
are selected for the output rails. Polymer capacitors have low
ESR and high current ripple rating. Connecting polymer
capacitors and MLCCs in parallel is very effective in reducing
voltage ripple. Two 330 µF POSCAP capacitors and two 22 µF
MLCCs are selected for each output.

MOSFET SELECTION

For low output or low duty cycle, select a high-side MOSFET
with fast rise and fall times and with low input capacitance to
minimize charging and switching power loss. For the synchronous
rectifier (low-side MOSFET), select a MOSFET with low R
because the switching speed is not critical and there is no switching
power loss in the low-side MOSFET.

The MOSFET IPD050N03L in PG-TO252-3-11 (DPA K ) from
Infineon is chosen for both the high-side and low-side MOSFETs
for a balance between low cost and good efficiency. The R
the IPD050N03L is about 6 mΩ at a V

of 5 V.

GS

DSON

DSON

of

Rev. 0 | Page 3 of 16

UG-334 Evaluation Board User Guide

100

90

80

70

60
50

40

30
20

10

0

0 2 4 6 8 10 12 14

LOAD (A)

EFFICIENCY (%)

10272-002

V

OUT2

= 1.8V

T

A

= 25°C

V

IN

= 12V

V

OUT1

= 5V

0

–0.005

–0.010

–0.015
–0.020

–0.025
–0.030

–0.035
–0.040

–0.045

–0.050

10 12 14 16 18 20

V

IN

(V)

LINE REGULATION (%)

10272-003

V

OUT2

= 1.8V

TA = 25°C
V

IN

= 12V WITH 5A LOAD

V

OUT1

= 5V

0

–0.05

–0.10

–0.15

–0.20

–0.25

–0.30

–0.35

–0.40

0 2 4 6

8 10 12 14

LOAD (A)

LOAD REGUL ATION (%)

10272-004

V

OUT2

= 1.8V

V

OUT1

= 5V

TA = 25°C

V

IN

= 12V

10272-005

CH1 20.0mV CH2 10. 0V M1.00µs A CH4 10.2V

1

4

2

3

B

W

CH3 20.0mV CH4 10.0V

B

W

SW1

SW2

T

V

OUT1

RIPPLE AT 10A

V

OUT2

RIPPLE AT 10A

10272-006

M20.0µs A CH4 7.60V

4

3

CH3 20.0mV CH4 5.00A Ω

B

W

T

V

OUT2

= 1.8V OUT P UT RESPONSE

V

OUT2

5A STEP LOAD

10272-007

M20.0µs A CH4 7.60V

4

3

CH3 20.0mV CH4 5. 00A Ω

B

W

T

V

OUT1

= OUTPUT RESPONSE

V

OUT1

5A STEP LOAD

TEST RESULTS

TA = 25°C.

Figure 2. Efficiency (Measurement Is Ma de with the Adjacent Channel Disabled)

Figure 5. Output Ripple, 10 A Load

Figure 3. Line Regulation

Figure 4. Load Regulation

Figure 6. Step Load Transient, V

OUT2

Figure 7. Step Load Transient, V

OUT1

Rev. 0 | Page 4 of 16

Evaluation Board User Guide UG-334

0.035

0.030

0.025

0.020

0.015

0.010

0.005

0

3.0 3.5

4.0 4.5 5.0 5.5 6.0
VINLDO (V)

LINE REGULATION (%)

10272-008

T

A

= 25°C

V

IN

= 12V

–0.02

–0.04
–0.06

–0.08

–0.10

–0.12

–0.14
–0.16
–0.18

–0.20

0

0 0.025 0.050 0.075 0.100 0.125 0.150 0.175 0.200

VOUTLDO LOAD (A)

LOAD REGUL ATION (%)

10272-009

VINLDO = 5V

VINLDO = 3V

T

A

= 25°C

V

IN

= 12V

10272-010

CH1 100mA Ω CH2 50.0mV

M10.0µs A CH1 118mA

1

2

B

W

T

STEP LOAD
1mA TO 200mA
C

INLDO

= 1µF, C

OUTLDO

= 4.7µF

OUTPUT TRANSIENT

Figure 8. VOUTLDO Line Regulation

Figure 10. VOUTLDO Step Load Response

Figure 9. VOUTLDO Load Regulation

Rev. 0 | Page 5 of 16

UG-334 Evaluation Board User Guide

OUT1

OUT1

OUT1

OUT1

OUT2

OUT2

V

OUT2

Ripple, DC Load

12 mV at 13 A load

OUT2

EVALUATION BOARD OPERATING INSTRUCTIONS

1. Connect Jumper J3 (EN1) to the high position to enable

Channel 1 of the ADP1876.

2. Connect Jumper J2 (EN2) to the high position to enable

Channel 2 of the ADP1876.

3. Connect the positive terminal of the input power supply to

the T1 input terminal. The input range is 10 V to 20 V,
which powers up the ADP1876 IC.

Table 1. Jumper Description

Default Factory

Jumper Description

Setting Function

J3 EN1 High Connect high to enable Channel 1 of the ADP1876, or connect low to disable the channel.
J2 EN2 High Connect high to enable Channel 2 of the ADP1876, or connect low to disable the channel.

Table 2. Performance Summary (TA = 25°C)

Parameter Condition

VIN 10 V to 20 V
fSW Switching frequency, 600 kHz
V

5 V

I

0 A to 13 A

V

Ripple, DC Load 12 mV at 13 A load

V

Deviation upon Step Load Release 0.8% with a 5 A step load

V

1.8 V

I

0 A to 13 A

4. Connect the positive terminal of another input power supply

to the T7 input terminal (VINLDO). The input range is

2.7 V to 5.5 V, which powers up the independent LDO.

V

Deviation upon Step Load Release 1.4% with a 5 A step load

Rev. 0 | Page 6 of 16

Evaluation Board User Guide UG-334

EVALUATION BOARD PCB LAYOUT

As seen in Figure 1, the layout of this evaluation board is not
optimized for the smallest PCB area. It is laid out in such a way
that any of the components can be desoldered and replaced
easily with different components with a hand soldering iron so
that the user can modify the existing design without acquiring
a new PCB layout. The physical size of the compensation
components is 0603, which is selected for its ease of hand
soldering when reworking the board is needed. The size of
these components can be 0402 or even smaller in the final
design. Note that there are extra placeholders for input bulk
capacitors, output filter capacitors, and MOSFETs. The user
can remove, add, or change any of these power components
to achieve a particular design objective. The track function,
where TRK1 is pulled up to VCCO through a 0 Ω dummy

resistor, is not used on this evaluation board. The primary
purpose of the TRK1 function is to discharge VOUT1 to GND
quickly when EN1 is pulled low and not relying on the feedback
resistors for discharging the output. To achieve a fast discharging
on the output, put an RC time delay at EN1 and a smaller RC time
delay at TRK1. Placeholders for these RC components have been
included on the evaluation board (see Figure 11 for details).

In addition, dummy 0 Ω resistors are placed at the driver gates,
DHx and DLx, for evaluation purposes only and can be removed
in the final design. Furthermore, many test points are placed on
the evaluation board so that the user can easily evaluate the per­formances of the ADP1876 with an oscilloscope. See Figure 11,
the evaluation board schematic, for more information.

Rev. 0 | Page 7 of 16

UG-334 Evaluation Board User Guide

Vin = 10V to 20V

VOUT2 = 1.8V

VOUT1 = 5V

TURRET

TURRET

TURRET

TURRET

TURRET

22pF

22pF

open

open

open

open

open

22uF

22uF

22uF

22uF

OPEN

to VEN1 (TP3)

VDL

OPEN

VOUT1

FB1

TRK1

VEN1

COMP1

EN1

VIN

VIN

VOUT2

DL1

SW1

SS1

DH2

SW2

VEN1

DL2

DH1

VDL

VIN

VCCO

VCCO

VIN

VIN

VIN

AGND

VINLDO

VOUTLDO

VDL

VCCO

VCCO

VINLDO

VOUTLDO

T7

TP-575-4

1

+

COV5

330uF

+

RC2

44.2k

+

CIN13

open

+

+

COV3

open

+

J3

2 Way Link

1

3

2

T2

123

4

CC21

330pF

TP15

1

L1

1.8uH

RR2

750k

T11

1

TP1TP1

1

TP8

1

TP16

1

RGCS2

22.6k

TP7TP7

1

CSS1

100nf

RT13

TP9TP9

1

Cin12

10uF

25V

CSNB2

U1

ADP1876-LFCSP

EN1

1

VIN

2

VINLDO

3

VOUTLDO

4

VCCO

5

VDL

6

EN2

9

FB2

10

COMP2

11

RAMP2

12

SS2

13

PGOOD2

14

ILIM2

15

BST2

16

SW2

17

DH2

18

PGND2

19

DL2

20

DL1

21

PGND1

22

DH1

23

SW1

24

AGND7NC

8

TRK1

32

FB1

31

COMP1

30

RAMP1

29

SS1

28

PGOOD1

27

ILIM1

26

BST1

25

QH3

IPD050N03L

CSNB1

RGCS1

22.6k

QH1

IPD050N03L

+

COV6

330uF

+

TP4

1

+

COV23

+

TP13TP13

1

RPG2

RF22

10k

+

COV8

open

+

Ctrk1OPEN

+

COV22

+

RSNB2

RF21

20k

+

COV7

open

+

CDR

1.0uF

+

CIN20

150uF

+

RSNB1

RF11

73.2k

T13

TP-575-4

1

RR1

750k

RT12

+

CIN10

open

+

T9

1

RILIM21

2.1K

CLIM1

CVIN

100nf

RDL1

0

T5

1

2

3

4

+

COV1

330uF

+

+

COV2

330uF

+

Cin11

10uF/25V

CBST1

100nf

+

COV4

open

+

L2

1.8uH

T6

1

2

3

4

T3

1

2

3

4

RILIM11

2.1K

CV5

1.0uF

TP12TP12

1

TP10

1

QH2

OPEN

TP14

1

+

COV12

+

TP11TP11

1

CIN22

10uF/25V

T12

1

COUTLDO

4.7uF

CLIM2

REN2

OPEN

RDH2

0

CC12

10pF

CINLDO

1uF

RF12

10K

RV5

open

QL4

OPEN

CC11

120pF

REN1

OPEN

T14

TP-575-4

1

QL3

IPD050N03L

TP2

1

RDL2

0

CIN21

10uF

25V

T8

1

TP6TP6

1

CEN1

OPEN

+

COV13

+

J2

2 Way Link

1

3

2

RC1

12.4k

T10

1

T4

1

2

3

4

QH4

OPEN

CSS2

100nF

CC22

22pF

RDH1

0

RVCC0

0

TP3

1

RPG1

open

QL2

IPD050N03L

+

CIN23

open

+

CBST2

100nf

QL1

OPEN

RT11

0

T1

123

4

10272-011

EVALUATION BOARD SCHEMATICS AND ARTWORK

Figure 11. Evaluation Board Schematic

Rev. 0 | Page 8 of 16

Evaluation Board User Guide UG-334

10272-012

10272-013

Figure 12. Top Silkscreen

Figure 13. Top Layer

Rev. 0 | Page 9 of 16

UG-334 Evaluation Board User Guide

10272-014

10272-015

Figure 14. Second Layer (AGND Plane)

Figure 15. Third Layer (PGND Layer)

Rev. 0 | Page 10 of 16

Evaluation Board User Guide UG-334

10272-016

Figure 16. Bottom Layer (PGND Layer)

Rev. 0 | Page 11 of 16

UG-334 Evaluation Board User Guide

ORDERING INFORMATION

BILL OF MATERIALS

Table 3.

Qty Reference Designator Description Manufacturer Part No.

1 U1 ADP1876, 32-lead LFCSP, 5 mm × 5 mm Analog Devices ADP1876
4 QH1, QH3, QL2, QL3 N MOSFET, 30 V, 6 mΩ Infineon IPD050N03L
2 L1, L2 Inductor, 1.8 µH, 3.5 mΩ, IN = 16 A, I
4 COV1, COV2, COV5, COV6 POSCAP, 330 µF, 6.3 V, 18 mΩ SANYO 6TPE330MFL
1 CIN20 OSCON, 150 µF, 20 V SANYO 20SEP150M
4 CIN11, CIN12, CIN21, CIN22 MLCC, 10 µF, X7R, 25 V Murata GRM32DR71E106KA12
1 CVIN MLCC, 100 nF, X7R, 25 V Murata GRM188R71E104KA01D
4 Css1, Css2, Cbst1, Cbst2 MLCC, 100 nF, X7R, 16 V Murata GRM188R71E104KA01
2 Cv5, Cdr MLCC, 1.0 µF, X5R, 6.3 V Murata GRM185R60J105KE21
4 COV13, COV23, COV12,

COV22
1 CINLDO MLCC, 1 µF,16 V, X7R Murata GRM188R71C105KA12
1 COUTLDO MLCC, 4.7 µF, 6.3 V, X5R Murata GRM188R0J475KE19
1 Cc11 MLCC, 120 pF Vishay VJ0603Y121KXAA
1 Cc12 MLCC, 10 pF Vishay VJ0603A100KXAA
1 Cc21 MLCC, 330 pF Vishay VJ0603Y331KXAA
3 Cc22, Clim1, Clim2 MLCC, 22 pF Vishay VJ0603A220KXAA
7 Rb0, Rvcco, RDH1, RDH2,

RDL1, RDL2, Rt11

2 Rgcs1, Rgcs2 Resistor, 22.6 kΩ Vishay CRCW06032262F
2 RR1, RR2 Resistor, 750 kΩ Vishay CRCW06031873F
2 Rf12, Rf22 Resistor, 10 kΩ Vishay CRCW06031002F
1 Rf11 Resistor, 73.2 kΩ Vishay CRCW06037322F
1 Rf21 Resistor, 20 kΩ Vishay CRCW06032002F
1 Rc1 Resistor, 124 kΩ Vishay CRCW06031243F
1 Rc2 Resistor, 44.2 kΩ Vishay CRCW06034422F
2 Rlim11, Rlim21 Resistor, 2.1 kΩ Vishay CRCW06032101F
2 J2, J3 3-terminal jumpers, 0.1" spacing Any
5 T8, T9, T10, T11, T12 Test points, turret, 110 mil thru hole Keystone Electronics Corp. 1502-1
6 T1, T2, T3, T4, T5, T6 Terminals Keystone Electronics Corp. 8191
3 T7, T13, T14 Banana plug Keystone Electronics Corp. 575-4

MLCC, 22 µF, X5R, 6.3 V Murata GRM31CR60J226ME19L

Resistor, 0 Ω Vishay CRCW06030R00F

= 18 A Würth Elektronic 744325180

SAT

Rev. 0 | Page 12 of 16

Evaluation Board User Guide UG-334

NOTES

Rev. 0 | Page 13 of 16

UG-334 Evaluation Board User Guide

NOTES

Rev. 0 | Page 14 of 16

Evaluation Board User Guide UG-334

NOTES

Rev. 0 | Page 15 of 16

UG-334 Evaluation Board User Guide

and between you (“Customer”) and Analog Devices, Inc.

BE LIABLE FOR ANY INCIDENTAL, SPECIAL, INDIRECT, OR CONSEQUENTIAL DAMAGES RESULTING FROM CUSTOMER’S POSSESSION OR USE OF

NOTES

ESD Caution
ESD (electrostatic discharge) sensitive device. Charged devices and circuit boards can discharge without detection. Although this product features patented or proprietary protection

circuitry, damage may occur on devices subjected to high e nergy ESD. Therefore, proper ESD precaution s should be taken to avoid performance degradation or loss of functionality.

Legal Terms and Conditions

By using the evaluation board discussed herein (together with any tools, components documentation or support materials, the “Evaluation Board”), you are agreeing to be bound by the terms and conditions
set forth below (“Agreement”) unless you have purchased the Evaluation Board, in which case the Analog Devices Standard Terms and Conditions of Sale shall govern. Do not use the Evaluation Board until you
have read and agreed to the Agreement. Your use of the Evaluation Board shall signify your acceptance of the Agreement. This Agreement is made by
(“ADI”), with its principal place of business at One Technology Way, Norwood, MA 02062, USA. Subject to the terms and conditions of the Agreement, ADI hereby grants to Customer a free, limited, personal,
temporary, non-exclusive, non-sublicensable, non-transferable license to use the Evaluation Board FOR EVALUATION PURPOSES ONLY. Customer understands and agrees that the Evaluation Board is provided
for the sole and exclusive purpose referenced above, and agrees not to use the Evaluation Board for any other purpose. Further more, the license granted is expressly made subject to the following additional
limitations: Customer shall not (i) rent, lease, display, sell, transfer, assign, sublicense, or distribute the Evaluation Board; and (ii) permit any Third Party to access the Evaluation Board. As used herein, the term
“Third Party” includes any entity other than ADI, Customer, their employees, affiliates and in-house consultants. The Evaluation Board is NOT sold to Customer; all rights not expressly granted herein, including
ownership of t he Evaluation Board, are res erved by ADI. CONFIDENTIALITY. This Agreement and the Evaluation Board shall all be considered the confidential and proprietary information of ADI. Customer ma y
not disclose or transfer any portion of the Evaluation Board to any other party for any reason. Upon discontinuation of use of the Evaluation Board or termination of this Agreement, Customer agrees to
promptly return the Evaluation Board to ADI. ADDITIONAL RESTRICTIONS. Customer may not disassemble, decompile or reverse engineer chips on the Evaluation Board. Customer shall inform ADI of any
occurred damages or any modifications or alterations it makes to the Evaluation Board, including but not limited to soldering or any other activity that affects the material content of the Evaluation Board.
Modifications to the Evaluation Board must comply with applicable law, including b ut not limited to the RoHS Directive. TERMINATION. ADI may terminate this Agreement at any time upon gi ving written noti ce
to Customer. Customer agrees to return to ADI the Evaluation Board at that time. LIMITATION OF LIABILITY. THE EVALUATION BOARD PROVIDED HEREUNDER IS PROVIDED “AS IS” AND ADI MAKES NO
WARRANTIES OR REPRES ENTATIONS OF ANY KIND WITH RESPECT TO IT. ADI SPECIFICAL LY DISC LAIMS ANY REPRESENTATIONS, ENDORSEMENTS, GUA RANTEES, OR WARRANT IES, EXPRESS OR IMPLIED, RELATED
TO THE EVALUATION BOARD INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTY OF MERCHANTABILITY, TITLE, FITNESS FOR A PARTICULAR PURPOSE OR NONINFRINGEMENT OF INTELLECTUAL
PROPERTY RIGHTS. IN NO EVENT WILL ADI AND ITS LICENSORS
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AMOUNT OF ONE HUNDRED US DOLLARS ($100.00). EXPORT. Customer agrees that it will not directly or indirectly export the Evaluation Board to another country, and that it will comply with all applicable
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Massachusetts (excluding conflict of law rules). Any legal action regarding this Agreement will be heard in the state or federal courts having jurisdiction in Suffolk County, Massachusetts, and Customer hereby
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©2011 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
UG10272-0-11/11(0)

Rev. 0 | Page 16 of 16