ANALOG DEVICES UG-437 Service Manual

Evaluation Board User Guide

UG-437

ADP1614

8

3

9

10

6

2

1

VIN

EN

CLRES

SS

SW

7

SW

FB

COMP

ON

OFF

5

GND

4

GND

11

EP

V

OUT

V

IN

L1

C

IN

C

SS

C

OUT

C

COMP

R

COMP

R

CL

R1

R2

D1

10859-001

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

Evaluating the ADP1614 650 kHz/1.3 MHz, 4 A, Step-Up, PWM,

DC-to-DC Switching Converter

FEATURES

2.5 V to 5.5 V input voltage range
650 kHz or 1.3 MHz fixed frequency options
Adjustable current limit up to 4 A
Output voltage

5 V for ADP1614-650-EVALZ

15 V for ADP1614-1.3-EVALZ
Jumper for enable/shutdown control
Components optimized for the indicated output voltages

GENERAL DESCRIPTION

The ADP1614 evaluation board is a complete step-up, dc-to-dc
switching converter application with components selected to allow
operation over the full range of input and load conditions for the
5 V (ADP1614-650-EVALZ) and 15 V (ADP1614-1.3-E VALZ)
output voltages. The boost switching frequency is fixed to either
650 kHz (ADP1614-650-EVALZ) or 1.3 MHz (ADP1614-1.3­EVALZ). The evaluation boards can be adjusted for different
output voltages by changing the feedback resistors, R1 and R2.
To ensure stable operation, external components L1, R
R

COMP

, and C

may also need to be recalculated and adjusted

COMP

when the output voltage is changed.

, C

CL

OUT

The ADP1614 evaluation board operates in current mode, pulse­width modulation (PWM) with up to 94% efficiency. The current
mode PWM architecture allows for excellent transient response,
easy noise filtering, and the use of small, cost-saving external
inductors and capacitors. Other key features include a 47 nF
soft start capacitor, undervoltage lockout (UVLO), thermal
shutdown (TSD), and jumper selected enable. The evaluation
board demonstrates the operation and performance of the

ADP1614.

This user guide includes I/O descriptions, setup instructions,
the schematic, and the PCB layout drawings for the ADP1614
step-up converter evaluation board.

Complete specifications for the ADP1614 are available in the

ADP1614 data sheet and should be consulted in conjunction

with this document when using the evaluation board.

,

TYPICAL APPLICATION CIRCUIT

Figure 1. Step-Up Regulator Configuration

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

Rev. 0 | Page 1 of 8

UG-437 Evaluation Board User Guide

TABLE OF CONTENTS

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

General Description ......................................................................... 1

Typical Application Circuit ............................................................. 1

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

Evaluation Board Hardware ............................................................ 3

Input/Output Connectors ........................................................... 3

REVISION HISTORY

7/12—Revision 0: Initial Version

Evaluation Setup ............................................................................3

Performance Evaluation ...............................................................3

Evaluation Board Schematic and Layout........................................4

Layout Guidelines..........................................................................4

Ordering Information .......................................................................5

Bill of Materials ..............................................................................5

Rev. 0 | Page 2 of 8

Evaluation Board User Guide UG-437

PLACE

JUMPER

HERE

10859-002

PLACE

JUMPER

HERE

10859-003

CONNECT

EXTERNAL

DEVICE

HERE

10859-004

ININ

OUTOUT

IVIV×

×

=η

EVALUATION BOARD HARDWARE

The ADP1614 evaluation board is fully assembled and tested.
The following sections describe the various connectors on the
board, the proper evaluation setup, and the testing capabilities
of the evaluation board.

INPUT/OUTPUT CONNECTORS

EN Test Bus

The EN connector is used to enable/disable the converter via
the EN pin. Use one of the following methods to enable the
converter. Do not leave the EN pin floating.

• Use a jumper to connect the top two pins of the EN test

bus. This connects EN to VIN and enables the converter
(see Figure 2).

Figure 2. Enabled Jumper Position

• Use a jumper to connect the bottom two pins of the EN test

bus. This connects EN to GND and disables the converter
(see Figure 3).

Figure 3. Disabled Jumper Position

• Alternatively, connect a voltage between VIN and GND to the

center pin of the EN test bus for independent control of the
EN pin voltage (see Figure 4).

Figure 4. EN Pin Direct Connection

VIN Test Bus

The VIN test bus connects the positive input supply voltage to
the VIN pin. Connect the power supply to this bus and keep the
wires as short as possible to minimize the EMI transmission.

SW Test Point

The SW test point is for monitoring the switch node (SW pin)
behavior and switching frequency. Connect a BNC cable to this
test point to measure the ADP1614 switching frequency.

VOUT Test Bus

The output voltage at the VOUT test bus is set by the resistive
voltage divider network, R1 and R2. A load can be attached
from the VOUT test bus to the GND test bus.

GND Test Bus

The GND test bus is the power ground connection for the part
via the GND pin as well as the bypass capacitors. Connect ground
connections from external equipment to this bus.

Rev. 0 | Page 3 of 8

EVALUATION SETUP

To ensure proper operation of the ADP1614 evaluation board:

1. Connect the input supply ground to GND.

2. Connect the positive input supply to VIN.

3. Connect the desired load between VOUT and GND. The

maximum continuous output current of the ADP1614 is
dependent upon the input and output voltage conditions.

4. Apply a voltage between 2.5 V and 5.5 V to the VIN test bus.

5. Move the jumper on the EN test bus to the enabled position.

If the feedback resistors, R1 and R2, are adjusted to change the
output voltage, recalculate the recommended values for the external
components (L1, R

, C

, R

CL

OUT

COMP

, and C

) using the applications

COMP

information from the ADP1614 data sheet.

PERFORMANCE EVALUATION

The following sections discuss tests and the resulting oscilloscope
waveforms. Oscilloscope waveforms and typical performance
characteristics are provided in the ADP1614 data sheet.

Line Regulation

The line regulation is observed and measured by monitoring
the output voltage (VOUT) while varying the input voltage (VIN).

Load Regulation

The load regulation is observed and measured by monitoring the
output voltage (VOUT) while sweeping the applied load between
VOUT and GND. To minimize voltage drop, use short low
resistance wires, especially for heavy loads.

Efficiency

The efficiency, η, is measured by comparing the input power to
the output power

Line Transient

The line transient performance is evaluated by generating a high
speed voltage transient on the input (VIN) and observing the
behavior of the evaluation board at the output (VOUT.)

Load Transient

The load transient performance is evaluated by generating a fast
current transient on the output (VOUT) and observing the
behavior of the evaluation board at the output (VOUT.)

Oscillator Frequency

The oscillator frequency can be measured by connecting an
oscilloscope to the SW pin.

Inductor Current

The inductor current is made accessible by removing one side
of the inductor from its pad and connecting a current loop in
series. Place an oscilloscope current probe on the loop to view
the current waveform.