Analog Devices ADP1875 Evaluation Board ADP1875-1.0-EVALZ ADP1875-1.0-EVALZ Data Sheet
Product codes
ADP1875-1.0-EVALZ
Synchronous Buck Controller with Constant
On-Time and Valley Current Mode
Data Sheet
Rev. A
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FEATURES
Power input voltage range: 2.95 V to 20 V
On-board bias regulator
Minimum output voltage: 0.6 V
0.6 V reference voltage with ±1.0% accuracy
Supports all N-channel MOSFET power stages
Available in 300 kHz, 600 kHz, and 1.0 MHz options
No current-sense resistor required
Power saving mode (PSM) for light loads (
On-board bias regulator
Minimum output voltage: 0.6 V
0.6 V reference voltage with ±1.0% accuracy
Supports all N-channel MOSFET power stages
Available in 300 kHz, 600 kHz, and 1.0 MHz options
No current-sense resistor required
Power saving mode (PSM) for light loads (
only)
Resistor programmable current limit
Power good with internal pull-up resistor
Externally programmable soft start
Thermal overload protection
Short-circuit protection
Standalone precision enable input
Integrated bootstrap diode for high-side drive
Starts into a precharged output
Available in a 16-lead QSOP package
Power good with internal pull-up resistor
Externally programmable soft start
Thermal overload protection
Short-circuit protection
Standalone precision enable input
Integrated bootstrap diode for high-side drive
Starts into a precharged output
Available in a 16-lead QSOP package
APPLICATIONS
Telecom and networking systems
Mid- to high-end servers
Set-top boxes
DSP core power supplies
Mid- to high-end servers
Set-top boxes
DSP core power supplies
GENERAL DESCRIPTION
The
are versatile current mode, synchronous
step-down controllers. They provide superior transient response,
optimal stability, and current-limit protection by using a constant
on-time, pseudo fixed frequency with a programmable current
limit, current control scheme. In addition, these devices offer
optimum performance at low duty cycles by using a valley, current
mode control architecture. This allows the
optimal stability, and current-limit protection by using a constant
on-time, pseudo fixed frequency with a programmable current
limit, current control scheme. In addition, these devices offer
optimum performance at low duty cycles by using a valley, current
mode control architecture. This allows the
the device and is capable of pulse skipping to maintain output
regulation while achieving improved system efficiency at light
loads (see the ADP1875 Power Saving Mode (PSM) section for
more information).
Available in three frequency options (300 kHz, 600 kHz, and
1.0 MHz, plus the PSM option), the
regulation while achieving improved system efficiency at light
loads (see the ADP1875 Power Saving Mode (PSM) section for
more information).
Available in three frequency options (300 kHz, 600 kHz, and
1.0 MHz, plus the PSM option), the
are well
suited for a wide range of applications that require a single-input
power supply range from 2.95 V to 20 V. Low voltage biasing is
supplied via a 5 V internal low dropout regulator (LDO).
power supply range from 2.95 V to 20 V. Low voltage biasing is
supplied via a 5 V internal low dropout regulator (LDO).
TYPICAL APPLICATIONS CIRCUIT
COMP
BST
FB
DRVH
GND
SW
VREG
VREG_IN
RES
DRVL
SS
C
SS
PGND
VIN
C
C
C
VREG
C
VREG2
C
C2
R
C
R
BOT
R
TOP
V
OUT
EN
10kΩ
VREG
Q1
Q2
L
C
OUT
V
OUT
C
BST
LOAD
C
IN
V
IN
= 2.95V TO 20V
ADP1874/
ADP1875
R
RES
R
TRK1
PGOOD
R
PGD
V
EXT
TRACK
R
TRK2
V
MASTER
09347-
001
Figure 1. Typical Applications Circuit
100
95
90
85
80
75
70
65
60
55
50
45
40
35
30
25
10
100
1k
10k
100k
E
F
F
ICI
E
NCY
(
%)
LOAD CURRENT (mA)
T
A
= 25°C
V
OUT
= 1.8V
f
SW
= 300kHz
WÜRTH INDUCTOR:
744325120, L = 1.2µH, DCR = 1.8mΩ
INFINEON FETs:
BSC042N03MS G (UPPER/LOWER)
INFINEON FETs:
BSC042N03MS G (UPPER/LOWER)
V
IN
= 5V (PSM)
V
IN
= 13V (PSM)
V
IN
= 16.5V (PSM)
V
IN
= 13V
V
IN
= 16.5V
09347-
102
Figure 2.
Efficiency vs. Load Current (V
OUT
= 1.8 V, 300 kHz)
In addition, soft start programmability is included to limit input
in-rush current from the input supply during startup and to
provide reverse current protection during precharged output
conditions. The low-side current sense, current gain scheme, and
integration of a boost diode, along with the PSM/forced pulse-
width modulation (PWM) option, reduce the external part count
and improve efficiency.
The
in-rush current from the input supply during startup and to
provide reverse current protection during precharged output
conditions. The low-side current sense, current gain scheme, and
integration of a boost diode, along with the PSM/forced pulse-
width modulation (PWM) option, reduce the external part count
and improve efficiency.
The
operate over the −40°C to +125°C
junction temperature range and are available in a 16-lead QSOP
package.
package.