Analog Devices ADP1872-EVALZ User Manual

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Evaluating the

FEATURES

Wide power input voltage (V
Bias supply voltage (V ) range: 2.75 V to 5.5 V
DD
Available in 1.8 V fixed-output voltage
Available in 300 kHz, 600 kHz, and 1.0 MHz switching
frequency options
Available in power saving mode (PSM) for light loads
(ADP1873 only)
Starts into a precharged or preloaded output

APPLICATIONS

Perform basic evaluation board operations
Evaluate IC and application board performance

GENERAL DESCRIPTION

This document describes the evaluation board hardware for the
ADP1872/ADP1873 PWM buck controllers. The evaluation boards
can be used to evaluate the ADP1872
circuits using these ICs without requiring any additional software.
The ADP1872/ADP1873 are versatile current-mode, synchronous
step-down controllers that provide superior transient response,
optimal stability, and current limit protection by using a constant
on-time, pseudo-fixed frequency with a programmable current-
sense gain, current-control scheme. The
saving mode (PSM) version of the device and is capable of pulse
skipping to maintain output regulation while achieving improved
system efficiency at light loads (see the
sheet for more information). Both devices are available in a small,
10-lead MSOP package and can operate over the −40°C to +125°C
temperature range.
The ADP1872/ADP1873 evaluation boards employ a power input
voltage (V ) that ranges between 2.75 V and 20 V and a bias supply
IN
voltage (V ) that ranges between 2.75 V and 5.5 V. Both inputs
DD
can be tied together for application input voltage conditions equal
to or less than 5.5 V. The evaluation board is available in a fixed-
output voltage option (V
OUT
600 kHz, or 1 MHz switching frequency (test trimmed in
production). The ADP1872/ADP1873
an output accuracy of 2% over the full temperature range and
provide a high input voltage (V
current up to 15 A.
See the last page for an important warning and disclaimers.
ADP1872-EVALZ/ADP1873-EVALZ User Guide
ADP1872/ADP1873
): 2.75 V to 20 V
IN
or ADP1873 and application
ADP1873 is the power
ADP1872/ADP1873
= 1.8 V), as well as in a 300 kHz,
evaluation boards offer
± 10%) and a full-scale load
IN
PWM Buck Controllers

TYPICAL APPLICATIONS CIRCUIT

C
C
R
C
R
TOP
V
OUT
R
C
VDD2
V = 2.75V
DD
TO 5.5V
C
VDD
data
Figure 2.
The ADP1872/ADP1873
including details about how to modify the evaluation board while
maintaining system stability throughout the entire load current
range and, therefore, should be consulted in conjunction with
this user guide when using the evaluation boards.
Rev. A | Page 1 of 20
V = 2.75V TO 20V
IN
VIN
ADP1872/
C
C2
ADP1873
COMP/EN BST
C
BST
FB DRVH
BOT
GND SW
VDD DRVL
PGND
R
RES
Figure 1.
ADP1872 Evaluation Board Configured
for 300 kHz Switching Frequency Operation
data sheet provides more information,
UG-057
C
IN
Q1
L
V
OUT
+
C
OUT
Q2
LOAD
5A