EVAL-ADP1715/ADP1716:ADP1715/ADP1716评估板 PDF

Evaluation Board for the
ADP1715/ADP1716
EVAL-ADP1715/ADP1716
FEATURES
GENERAL DESCRIPTION
Input voltage range: 2.5 V to 5.5 V
Output current range: 0 mA to 500 mA
Output voltage accuracy: ±1%
Operating temperature range: –40°C to +125°C
The ADP1715/ADP1716 evaluation board can be used to demonstrate the functionality of the ADP1715/ADP1716 series of
linear regulators. Depending on the component combinations
used, the evaluation board can be used for ADP1715 fixed output
voltage devices with soft start, ADP1715 adjustable output voltage
devices, and ADP1716 fixed output voltage devices with tracking.
Simple device measurements such as line and load regulation,
dropout, and ground current can be demonstrated with just a
single voltage supply, a voltage meter, a current meter, and load
resistors.
For more details about the ADP1715/ADP1716 linear
regulators, visit www.analog.com.
EVALUATION BOARD
EVAL-ADP1715/ADP1716
GND
GND
U1
C1
C2
C3
J1
R2
R1
GND
VOUT
EN
SS/ADJ/TRK
GND
06309-001
VIN
Figure 1.
Rev. 0
Evaluation boards are only intended for device evaluation and not for production purposes.
Evaluation boards as supplied “as is” and without warranties of any kind, express, implied, or
statutory including, but not limited to, any implied warranty of merchantability or fitness for a
particular purpose. No license is granted by implication or otherwise under any patents or other
intellectual property by application or use of evaluation boards. Information furnished by Analog
Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog
Devices for its use, nor for any infringements of patents or other rights of third parties that may result
from its use. Analog Devices reserves the right to change devices or specifications at any time
without notice. Trademarks and registered trademarks are the property of their respective owners.
Evaluation boards are not authorized to be used in life support devices or systems.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113
©2007 Analog Devices, Inc. All rights reserved.
EVAL-ADP1715/ADP1716
TABLE OF CONTENTS
Features .............................................................................................. 1
Line Regulation..............................................................................5
General Description ......................................................................... 1
Load Regulation ............................................................................6
Evaluation Board .............................................................................. 1
Dropout Voltage ............................................................................6
Revision History ............................................................................... 2
Ground Current Measurements ......................................................7
Evaluation Board Hardware and Schematic ................................. 3
Ground Current Consumption ...................................................7
Evaluation Board Configurations................................................... 4
Ordering Information.......................................................................8
ADP1715 Fixed Output with Soft Start..................................... 4
Bill of Materials..............................................................................8
ADP1715 Adjustable Output ...................................................... 4
Ordering Guide .............................................................................8
ADP1716 Fixed Output with Tracking...................................... 4
ESD Caution...................................................................................8
Output Voltage Measurements ....................................................... 5
REVISION HISTORY
3/07—Revision 0: Initial Version
Rev. 0 | Page 2 of 8
EVAL-ADP1715/ADP1716
EVALUATION BOARD HARDWARE AND SCHEMATIC
GND
GND
VIN
J1
C1
EN
SS/ADJ/TRK
1
EN
GND 8
2
IN
GND 7
3
OUT
GND 6
4
SS/ADJ/TRK
GND 5
U1
C2
C3
R1
GND
GND
06309-002
R2
VOUT
Figure 2. Evaluation Board Schematic
Table 1. Components Listing
Reference
Designator
U1 1
C1
C2
C3 2
R1, R2 3
J1
Function
Linear regulator
Input capacitor
Output capacitor
Soft start capacitor
Output voltage adjust resistors
Jumper
Description
ADP1715/ADP1716 Low Dropout Linear Regulator.
2.2 μF Input Bypass Capacitor.
2.2 μF Output Capacitor. Required for stability and transient performance.
10 nF Soft Start Capacitor. Determines VOUT ramp-up time during startup.
External Resistors. Used to set VOUT with the ADP1715 adjustable version.
Jumper. Connects EN to VIN for automatic startup.
1
Component varies depending on which evaluation board model is ordered.
Component present only on boards with ADP1715 fixed output devices.
3
Components present only on boards with ADP1715 adjustable output devices.
2
Rev. 0 | Page 3 of 8
EVAL-ADP1715/ADP1716
EVALUATION BOARD CONFIGURATIONS
The output voltage is set based on the equation
The ADP1715/ADP1716 evaluation boards come supplied with
different components depending on which version is ordered.
Components common to all versions are C1, C2, and J1.
For example, if R1 = 10 kΩ and R2 = 4.99 kΩ, then VOUT = 2.403 V.
ADP1715 FIXED OUTPUT WITH SOFT START
ADP1716 FIXED OUTPUT WITH TRACKING
Evaluation boards that come supplied with ADP1715 fixed
output voltage option devices have the C3 soft start capacitor
included. This capacitor controls the rise time when the output
voltage starts up. Figure 3 shows the schematic of this evaluation board configuration.
Evaluation boards that come supplied with ADP1716 fixed
output voltage option with tracking devices do not have C3,
R1, or R2 populated. The user can instead connect an external
voltage to the TRK pad of the evaluation board to see how the
track feature works. Figure 5 shows the schematic of this
evaluation board configuration.
ADP1715
J1
1
EN
GND 8
2
IN
GND 7
3
C1
4
OUT
ADP1716
J1
GND 6
SS
VIN
GND 5
C1
06309-003
U1
C2
C3
VOUT
VOUT
ADP1715
ADJUSTABLE
1
EN
GND 8
2
IN
GND 7
3
OUT
GND 6
4
ADJ
GND 5
VOUT
C2
R2
U1
06309-004
R1
GND 8
2
IN
GND 7
3
OUT
GND 6
4
TRK
GND 5
U1
Figure 5. ADP1716 Fixed Output with Tracking
Evaluation boards that come supplied with ADP1715 adjustable
output voltage option devices have the R1 and R2 resistors
included. Figure 4 shows the schematic of this evaluation board
configuration.
C1
EN
TRK
ADP1715 ADJUSTABLE OUTPUT
VIN
1
C2
Figure 3. ADP1715 Fixed Output with Soft Start
J1
(1)
Figure 4. ADP1715 Adjustable Output
Rev. 0 | Page 4 of 8
06309-005
VIN
VOUT = 0.8 V (1 + R1/R2)
EVAL-ADP1715/ADP1716
OUTPUT VOLTAGE MEASUREMENTS
VOLTAGE
SOURCE
GND
EVAL-ADP1715/ADP1716
VOLTAGE
METER
V
GND
U1
–
C1
+
C2
C3
J1
R2
R1
VOUT
VIN
GND
EN
SS/ADJ/TRK
06309-006
LOAD
GND
Figure 6.
1.
2.
3.
4.
5.
Connect the negative terminal (–) of the voltage source to
one of the GND pads on the evaluation board.
Connect the positive terminal (+) of the voltage source to
the VIN pad of the evaluation board.
Connect a load between the VOUT pad and one of the
GND pads.
Connect the negative terminal (–) of the voltage meter to
one of the GND pads and the positive terminal (+) of the
voltage meter to the VOUT pad.
The voltage source can now be turned on. If J1 is inserted
(this connects EN to VIN for automatic startup), then the
regulator powers up.
For line regulation measurements, the regulator output is
monitored while its input is varied. For good line regulation,
the output must change as little as possible with varying input
levels. To ensure the device is not in dropout mode during this
measurement, VIN must be varied between VOUTNOM + 0.5 V
(or 2.5 V, whichever is greater) and VINMAX. For an ADP1715
with a 3.3 V fixed output, this means VIN needs to be varied
between 3.8 V and 5.5 V. This measurement can be repeated
under different load conditions. Figure 7 shows the typical line
regulation performance of an ADP1715 with 3.3 V fixed output.
If large load currents are to be used, the user needs to connect
the voltage meter as close to the output capacitor as possible, to
reduce the effects of IR drops.
3.325
3.315
ILOAD = 100µA
3.305
ILOAD = 10mA
3.295
ILOAD = 100mA
ILOAD = 250mA
3.285
3.265
3.3
ILOAD = 360mA
ILOAD = 500mA
3.275
06309-007
Follow these steps to connect to a voltage source and voltage meter:
LINE REGULATION
VOUT (V)
Figure 6 shows how the evaluation board can be connected to
a voltage source and a voltage meter for basic output voltage
accuracy measurements. A resistor can be used as the load for
the regulator. Ensure the resistor has a power rating adequate
to handle the power expected to be dissipated across it. An electronic load can be used as an alternative. Ensure the voltage source
used can supply adequate current for the expected load levels.
3.8
4.3
4.8
VIN (V)
Figure 7. ADP1715 Line Regulation
Rev. 0 | Page 5 of 8
5.3
EVAL-ADP1715/ADP1716
LOAD REGULATION
DROPOUT VOLTAGE
For load regulation measurements, the regulator output is
monitored while the load is varied. For good load regulation,
the output needs to change as little as possible with varying
loads. The input voltage must be held constant during this
meas-urement. The load current can be varied from 0 mA
to 500 mA. Figure 8 shows the typical load regulation
performance of an ADP1715 with 3.3 V fixed output for
an input voltage of 3.8 V.
Dropout voltage measurements can also be performed using
the configuration shown in Figure 6. Dropout voltage is defined
as the input-to-output voltage differential when the input
voltage is set to the nominal output voltage. This applies only
for output voltages above 2.5 V. Dropout voltage increases with
larger loads. For more accurate measurements, a second voltage
meter can be used to monitor the input voltage across the input
capacitor. The input supply voltage may need to be adjusted to
account for IR drops, especially if large load currents are used.
Figure 9 shows a typical curve of dropout voltage measurements
with different load currents.
3.325
3.315
350
300
3.295
VDROPOUT (mV)
250
3.285
3.275
1
10
100
200
150
100
1000
50
ILOAD (mA)
Figure 8. ADP1715 Load Regulation
0
0.1
06309-009
3.265
0.1
06309-008
VOUT (V)
3.305
1
10
100
ILOAD (mA)
Figure 9. Dropout Voltage vs. Load Current
Rev. 0 | Page 6 of 8
1000
EVAL-ADP1715/ADP1716
GROUND CURRENT MEASUREMENTS
VOLTAGE SOURCE
CURRENT METER
µA
EVAL-ADP1715/ADP1716
U1
GND
GND
C1
LOAD
C2
C3
J1
R2
R1
VOUT
GND
EN
SS/ADJ/TRK
06309-010
VIN
GND
Figure 10.
Figure 10 shows how the evaluation board can be connected to
a voltage source and a current meter for ground current measurements. A resistor can be used as the load for the regulator. Ensure
that the resistor has a power rating adequate to handle the power
expected to be dissipated across it. An electronic load can be
used as an alternative. Ensure the voltage source used can supply
adequate current for the expected load levels.
the regulator consumes maximum current when supplying its
largest load level (500 mA). Figure 11 shows typical ground
current consumption for various load levels.
500
450
400
350
2.
3.
4.
5.
Connect the positive terminal (+) of the voltage source to
the VIN pad on the evaluation board.
Connect the positive terminal (+) of the current meter to
one of the GND pads of the evaluation board.
Connect the negative terminal (–) of the current meter to
the negative terminal (–) of the voltage source.
Connect a load between the VOUT pad of the evaluation
board and the negative terminal (–) of the voltage source.
The voltage source can now be turned on. If J1 is inserted
(this connects EN to VIN for automatic startup), then the
regulator powers up.
GROUND CURRENT CONSUMPTION
Ground current measurements are a way of determining how
much current the regulator internal circuits are consuming
while performing the regulation function. To be efficient, the
regulator must consume as little current as possible. Typically,
300
250
200
150
100
06309-011
1.
IGND (µA)
Follow these steps to connect to a voltage source and current meter:
50
0
0.1
1
10
100
1000
ILOAD (mA)
Figure 11. Ground Current vs. Load Current
When the device is disabled (EN = 0 V), ground current is
reduced to less than 1 μA.
Note that larger ground current levels are observed when using
an evaluation board with R1 and R2 present.
Rev. 0 | Page 7 of 8
EVAL-ADP1715/ADP1716
ORDERING INFORMATION
BILL OF MATERIALS
Table 2.
Qty
Reference Designator
Description
Manufacturer/Vendor
Vendor Part Number
2
1
1
C1, C2
C3
R1
Capacitor, MLCC, 2.2 μF, 16 V, 0805, X5R
Capacitor, MLCC, 10 nF, 100 V, 0805, X7R
Resistor, 10 kΩ, 1%, 0805
Murata or equivalent
Murata or equivalent
Vishay Dale or equivalent
GRM21BR61C225KA88
GRM21BR72A103KA01
CRCW080510K0FKEA
1
1
1
R2
J1
U1
Resistor, 4.99 kΩ, 1%, 0805
Header, single, STR, 2 pins
IC, LDO regulator
Vishay Dale or equivalent
Digi-Key, Corp.
Analog Devices, Inc.
CRCW08054K990FKEA
S1012E-36-ND
ADP1715ARMZ-R7
ADP1715ARMZ-3.3-R7
ADP1715ARMZ-1.8-R7
ADP1716ARMZ-2.5-R7
ORDERING GUIDE
Model
ADP1715-EVALZ1
ADP1715-3.3-EVALZ1
ADP1715-1.8-EVALZ1
ADP1716-2.5-EVALZ1
1
ESD CAUTION
Description
Evaluation Board with
Adjustable Output ADP1715
Evaluation Board with 3.3 V
Fixed Output ADP1715
Evaluation Board with 1.8 V
Fixed Output ADP1715
Evaluation Board with 2.5 V
Fixed Output ADP1716
Z = RoHS Compliant Part.
©2007 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
EB06309-0-3/07(0)
Rev. 0 | Page 8 of 8