50 mA, High Voltage,
Micropower Linear Regulator
ADP1720
Rev. A
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FEATURES
Wide input voltage range: 4 V to 28 V
Maximum output current: 50 mA
Low light load current:
28 μA at 0 μA load
35 μA at 100 μA load
Low shutdown current: 0.7 μA
Low dropout voltage: 275 mV @ 50 mA load
Initial accuracy: ±0.5%
Accuracy over line, load, and temperature: ±2%
Stable with small 1μF ceramic output capacitor
Fixed 3.3 V and 5.0 V output voltage options
Adjustable output voltage option: 1.225 V to 5.0 V
Current limit and thermal overload protection
Logic controlled enable
Space-saving thermally enhanced MSOP package
APPLICATIONS
DC-to-DC post regulation
PCMCIA regulation
Keep-alive power in portable equipment
Industrial applications
TYPICAL APPLICATION CIRCUITS
GND
1 8
GND
2
GND
3
GND
4
7
6
GND
IN
OUT
EN
5
ADP1720
FIXED
V
IN
= 28V
V
OUT
= 5V
1µF
1µF
06111-001
Figure 1. ADP1720 with Fixed Output Voltage, 5.0 V
GND
1
GND
2
GND
3
GND
4
8
7
6
ADJ
IN
OUT
EN
5
ADP1720
ADJUSTABLE
V
IN
= 12V
V
OUT
=
1.225V(1 + R1/R2)
1µF
1µF
R1
R2
06111-002
Figure 2. ADP1720 with Adjustable Output Voltage, 1.225 V to 5.0 V
GENERAL DESCRIPTION
The ADP1720 is a high voltage, micropower, low dropout linear
regulator. Operating over a very wide input voltage range of 4 V
to 28 V, the ADP1720 can provide up to 50 mA of output current.
With just 28 μA of quiescent supply current and a micropower
shutdown mode, this device is ideal for applications that require
low quiescent current.
The ADP1720 is available in fixed output voltages of 3.3 V and
5.0 V. An adjustable version is also available, which allows the
output to be set anywhere between 1.225 V and 5.0 V. An enable
function that allows external circuits to turn on and turn off the
ADP1720 output is available. For automatic startup, the enable
(EN) pin can be connected directly to the input rail.
The ADP1720 is optimized for stable operation with small 1 μF
ceramic output capacitors, allowing for good transient perform-
ance while occupying minimal board space.
The ADP1720 operates from –40°C to +125°C and uses current
limit protection and thermal overload protection circuits to
prevent damage to the device in adverse conditions.
Available in a small thermally enhanced MSOP package, the
ADP1720 provides a compact solution with low thermal resistance.
ADP1720
Rev. A | Page 2 of 16
TABLE OF CONTENTS
Features .............................................................................................. 1
Applications ....................................................................................... 1
Typical Application Circuits ............................................................ 1
General Description ......................................................................... 1
Revision History ............................................................................... 2
Specifications ..................................................................................... 3
Absolute Maximum Ratings ............................................................ 5
Thermal Resistance ...................................................................... 5
ESD Caution .................................................................................. 5
Pin Configurations and Function Descriptions ........................... 6
Typical Performance Characteristics ..............................................7
Theory of Operation ...................................................................... 10
Adjustable Output Voltage (ADP1720 Adjustable) ............... 10
Applications Information .............................................................. 11
Capacitor Selection .................................................................... 11
Current Limit and Thermal Overload Protection ................. 11
Thermal Considerations ............................................................ 12
Printed Circuit Board Layout Considerations ....................... 14
Outline Dimensions ....................................................................... 15
Ordering Guide .......................................................................... 15
REVISION HISTORY
7/07—Rev. 0 to Rev. A
Change to Figure 1 ........................................................................... 1
Changes to Table 1 ............................................................................ 3
Changes to Ordering Guide .......................................................... 15
2/07—Revision 0: Initial Version
ADP1720
Rev. A | Page 3 of 16
SPECIFICATIONS
VIN = 12 V, IOUT = 100 μA, CIN = COUT = 1 μF, TA = 25°C, unless otherwise noted.
Table 1.
Parameter Symbol Conditions Min Typ Max Unit
INPUT VOLTAGE RANGE VIN T
J = –40°C to +125°C 4 28 V
OPERATING SUPPLY CURRENT IGND I
OUT = 0 μA 28 μA
I
OUT = 0 μA,
V
IN =
V
OUT + 0.5
V
or 4
V
(whichever is
greater), TJ = –40°C to +125°C
80 μA
I
OUT = 100 μA 35 μA
IOUT = 100 μA, VIN = VOUT + 0.5 V or 4 V (whichever is
greater), TJ = –40°C to +125°C
120 μA
I
OUT = 1 mA 74 μA
IOUT = 1 mA, VIN = VOUT + 0.5 V or 4 V (whichever is
greater), TJ = –40°C to +125°C
340 μA
I
OUT = 10 mA 300 μA
IOUT = 10 mA, VIN = VOUT + 0.5 V or 4 V (whichever is
greater), TJ = –40°C to +125°C
900 μA
100 μA < IOUT < 50 mA, VIN = VOUT + 0.5 V or 4 V
(whichever is greater), TJ = –40°C to +125°C
1185 2115 μA
SHUTDOWN CURRENT IGND-SD EN = GND 0.7 μA
EN = GND, TJ = –40°C to +125°C 1.5 μA
OUTPUT
Fixed Output VOUT I
OUT = 100 μA –0.5 +0.5 %
Voltage Accuracy 100 μA < IOUT < 50 mA –1 +1 %
100 μA < IOUT < 50 mA, TJ = –40°C to +125°C –2 +2 %
Adjustable Output1
VOUT I
OUT = 100 μA 1.2188 1.2250 1.2311 V
Voltage Accuracy 100 μA < IOUT < 50 mA 1.2127 1.2372 V
100 μA < IOUT < 50 mA, TJ = –40°C to +125°C 1.2005 1.2495 V
Noise (10 Hz to 100 kHz) OUTNOISE VOUT = 1.6 V, COUT = 1 μF 146 μV rms
VOUT = 1.6 V, COUT = 10 μF 124 μV rms
VOUT = 5 V, COUT = 1 μF 340 μV rms
VOUT = 5 V, COUT = 10 μF 266 μV rms
REGULATION
Line Regulation ∆VOUT/∆VIN V
IN = (VOUT + 0.5 V) to 28 V, TJ = –40°C to +125°C –0.02 +0.02 %/ V
Load Regulation2∆VOUT/∆IOUT 1 mA < IOUT < 50 mA 0.001 %/mA
1 mA < IOUT < 50 mA, TJ = –40°C to +125°C 0.005 %/mA
DROPOUT VOLTAGE3
VDROPOUT I
OUT = 10 mA 55 mV
I
OUT = 10 mA, TJ = –40°C to +125°C 105 mV
I
OUT = 50 mA 275 mV
I
OUT = 50 mA, TJ = –40°C to +125°C 480 mV
START-UP TIME4
TSTART-UP 200 μs
CURRENT LIMIT THRESHOLD5
ILIMIT 55 90 140 mA
THERMAL CHARACTERISTICS
Thermal Shutdown
Threshold
TSSD T
J rising 150 °C
Thermal Shutdown
Hysteresis
TSSD-HYS 15 °C
EN CHARACTERISTICS
EN Input
Logic High VIH 4 V ≤ VIN ≤ 28 V 1.8 V
Logic Low VIL 4 V ≤ VIN ≤ 28 V 0.4 V
Leakage Current VI-LEAKAGE EN = GND 0.1 1 μA
EN = IN 0.5 1 μA
ADJ INPUT BIAS CURRENT
(ADP1720 ADJUSTABLE)
ADJI-BIAS 30 100 nA
ADP1720
Rev. A | Page 4 of 16
Parameter Symbol Conditions Min Typ Max Unit
POWER SUPPLY REJECTION RATIO PSRR f = 120 Hz, VIN = 8 V, VOUT = 1.6 V –90 dB
f = 1 kHz, VIN = 8 V, VOUT = 1.6 V –80 dB
f = 10 kHz, VIN = 8 V, VOUT = 1.6 V –60 dB
f = 120 Hz, VIN = 8 V, VOUT = 5 V –83 dB
f = 1 kHz, VIN = 8 V, VOUT = 5 V –70 dB
f = 10 kHz, VIN = 8 V, VOUT = 5 V –50 dB
1 Accuracy when OUT is connected directly to ADJ. When OUT voltage is set by external feedback resistors, absolute accuracy in adjust mode depends on the tolerances
of resistors used.
2 Based on an end-point calculation using 1 mA and 50 mA loads. See Fi for typical load regulation performance for loads less than 1 mA. gure 6
3 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 4 V.
4 Start-up time is defined as the time between the rising edge of EN to OUT being at 95% of its nominal value.
5 Current limit threshold is defined as the current at which the output voltage drops to 90% of the specified typical value. For example, the current limit for a 5.0 V
output voltage is defined as the current that causes the output voltage to drop to 90% of 5.0 V, or 4.5 V.
ADP1720
Rev. A | Page 5 of 16
ABSOLUTE MAXIMUM RATINGS
Table 2.
Parameter Rating
IN to GND –0.3 V to +30 V
OUT to GND –0.3 V to IN or +6 V
(whichever is less)
EN to GND –0.3 V to +30 V
ADJ to GND –0.3 V to +6 V
Storage Temperature Range –65°C to +150°C
Operating Junction
Temperature Range
–40°C to +125°C
Soldering Conditions JEDEC J-STD-020
Stresses above those listed under Absolute Maximum Ratings
may cause permanent damage to the device. This is a stress
rating only; functional operation of the device at these or any
other conditions above those indicated in the operational
section of this specification is not implied. Exposure to absolute
maximum rating conditions for extended periods may affect
device reliability.
THERMAL RESISTANCE
θJA is specified for the worst-case conditions, that is, a device
soldered in a circuit board for surface-mount packages.
Table 3. Thermal Resistance
Package Type θJA θ
JC Unit
8-Lead MSOP 118 57 °C/W
ESD CAUTION
ADP1720
Rev. A | Page 6 of 16
PIN CONFIGURATIONS AND FUNCTION DESCRIPTIONS
06111-003
GND
GND
GND
ADJ
IN
OUT
GND
GND
GND
GND
IN
OUT
GNDEN
1
2
3
4
8
7
6
5
ADP1720
FIXED
GNDEN
1
2
3
8
7
6
TOP VIEW
(No t t o S cale)
4
ADP1720
ADJUSTABLE
TO P VIE W
(No t to S cal e)
5
06111-004
Figure 3. 8-Lead MSOP Figure 4. 8-Lead MSOP
Table 4. Pin Function Descriptions
ADP1720
Fixed
Pin No.
ADP1720
Adjustable
Pin No. Mnemonic Description
1 N/A GND This pin is internally connected to ground.
N/A 1 ADJ Adjust. A resistor divider from OUT to ADJ sets the output voltage.
2 2 IN Regulator Input Supply. Bypass IN to GND with a 1 μF or greater capacitor.
3 3 OUT Regulated Output Voltage. Bypass OUT to GND with a 1 μF or greater capacitor.
4 4 EN Enable Input. Drive EN high to turn on the regulator; drive it low to turn off the regulator. For
automatic startup, connect EN to IN.
5 5 GND Ground.
6 6 GND Ground.
7 7 GND Ground.
8 8 GND Ground.
ADP1720
Rev. A | Page 7 of 16
4.96 –40
TYPICAL PERFORMANCE CHARACTERISTICS
VIN = 12 V, VOUT = 5 V, IOUT = 100 μA, CIN = COUT = 1 μF, TA = 25°C, unless otherwise noted.
5.03
V
OUT
(V)
T
J
(°C)
5.02
5.01
5.00
4.99
4.98
4.97
–5 25 85 125
I
LOAD
= 10µA
I
LOAD
= 100µ A
I
LOAD
= 1mA
I
LOAD
= 10mA
I
LOAD
= 25mA
I
LOAD
= 50mA
06
0.01 100
111-005
Figure 5. Output Voltage vs. Junction Temperature
ILOAD (mA)
VOUT (V)
0.1 1 10
4.9965
4.9970
4.9975
4.9980
4.9985
4.9990
4.9995
5.0000
5.0005
5.0010
5.0015
06
4.990 03
V
IN
(V)
111-006
Figure 6. Output Voltage vs. Load Current
5.010
V
OUT
(V)
0
5.008
5.006
5.004
5.002
5.000
4.998
4.996
4.994
4.992
5 10152025
I
LOAD
= 10µA
I
LOAD
= 100µ A
I
LOAD
= 1mA
I
LOAD
= 10mA
I
LOAD
= 25mA
I
LOAD
= 50mA
06111-007
Figure 7. Output Voltage vs. Input Voltage
1200
0–40
T
J
(°C)
I
GND
(µA)
1000
800
600
400
200
–5 25 85 125
I
LOAD
= 50mA
I
LOAD
= 25mA
I
LOAD
= 10mA
I
LOAD
= 1mA
I
LOAD
= 100µA
I
LOAD
= 10µA
06111-008
Figure 8. Ground Current vs. Junction Temperature
1200
0
0.01 100
I
LOAD
(mA)
I
GND
(µA)
0.1 1 10
1000
800
600
400
200
06111-009
Figure 9. Ground Current vs. Load Current
1400
003
V
IN
(V)
I
GND
(µA)
0
1200
1000
800
600
400
200
5 10152025
I
LOAD
= 50mA
I
LOAD
= 25mA
I
LOAD
= 10mA
I
LOAD
= 1mA
I
LOAD
= 100µ A
I
LOAD
= 10µA
06111-010
Figure 10. Ground Current vs. Input Voltage
ADP1720
Rev. A | Page 8 of 16
0
300
V
DROPOUT
(mV)
11
I
LOAD
(mA)
00
10
250
200
150
100
50
06111-011
4.60
4.9 5.4
V
IN
(V)
Figure 11. Dropout Voltage vs. Load Current
5.05
V
OUT
(V)
5.00
4.95
4.90
4.85
4.80
4.75
4.70
4.65
5.0 5.1 5.2 5.3
I
LOAD
= 50mA
I
LOAD
= 25mA
I
LOAD
= 10mA
I
LOAD
= 1mA
06111-012
Figure 12. Output Voltage vs. Input Voltage (in Dropout)
3.5
0
4.9 5.4
V
IN
(V)
I
GND
(mA)
3.0
2.5
2.0
1.5
1.0
0.5
5.0 5.1 5.2 5.3
I
LOAD
=
50mA
I
LOAD
=
25mA
I
LOAD
=
10mA
I
LOAD
=
1mA
06111-013
Figure 13. Ground Current vs. Input Voltage (in Dropout)
0
–10010 10M
FREQUENCY (Hz )
PSRR (dB)
100 1k 10k 100k 1M
–10
–20
–30
–40
–50
–60
–70
–80
–90
100µA
10mA
1mA
VIN = 8V
VOUT = 1.6V
COUT = 1µF
VRIPPLE = 50mV
06111-014
Figure 14. Power Supply Rejection Ratio vs. Frequency
(1.6 V Adjustable Output)
ADP1720
Rev. A | Page 9 of 16
–10010 10M
PSRR (dB)
0
FREQUENCY (Hz )
100 1k 10k 100k 1M
VIN = 8V
VOUT = 5V
COUT = 1µF
VRIPPLE = 50mV
–10
–20
–30
–40
–50
–60
–70
–80
–90
1mA 10mA
100µA
06111-015
Figure 15. Power Supply Rejection Ratio vs. Frequency
(5.0 V Fixed Output)
TI M E (20µs/ DIV)
10mV/DI
V
1
VIN = 12V
VOUT = 1.6V
CIN = 1µF
COUT = 1µF
LOAD STEP FROM 2.5m A TO 47.5mA
06111-016
VOUT
Figure 16. Load Transient Response
TI ME ( 100µs/DIV)
10mV/DI
V
2
2V/DI
V
1
VOUT = 5V
CIN = 1µF
COUT = 1µF
ILOAD = 50mA
06111-017
VIN STEP FROM 6V TO 7V
VOUT
Figure 17. Line Transient Response
TI M E (40µs/ DIV)
2V/DI
V
2
5V/DI
V
1
VIN = 12V
VOUT = 5V
CIN = 1µF
COUT = 1µF
ILOAD = 50mA
06111-018
EN
VOUT
Figure 18. Start-Up Time
ADP1720
Rev. A | Page 10 of 16
THEORY OF OPERATION
The ADP1720 is a low dropout, BiCDMOS linear regulator that
operates from a 4 V to 28 V input rail and provides up to 50 mA
of output current. Ground current in shutdown mode is typically
700 nA. The ADP1720 is stable and provides high power supply
rejection ratio (PSRR) and excellent line and load transient
response with just a small 1 μF ceramic output capacitor.
REFERENCE
CURRENT LIM IT
THERMAL PROTECT
SHUTDOWN
OUT
GND/ADJ
IN
EN
19
GND
06111-0
Figure 19. Internal Block Diagram
Internally, the ADP1720 consists of a reference, an error ampli-
fier, a feedback voltage divider, and a DMOS pass transistor.
Output current is delivered via the DMOS pass device, which is
controlled by the error amplifier. The error amplifier compares
the reference voltage with the feedback voltage from the output
and amplifies the difference. If the feedback voltage is lower than
the reference voltage, the gate of the DMOS device is pulled
lower, allowing more current to pass and increasing the output
voltage. If the feedback voltage is higher than the reference
voltage, the gate of the PNP device is pulled higher, allowing
less current to pass and decreasing the output voltage.
The ADP1720 is available in two versions, one with fixed output
voltage options (see Figure 1) and one with an adjustable output
voltage (see Figure 2). The fixed output voltage options are set
internally to either 5.0 V or 3.3 V, using an internal feedback
network. The adjustable output voltage can be set to between
1.225 V and 5.0 V by an external voltage divider connected from
OUT to ADJ. The ADP1720 uses the EN pin to enable and
disable the OUT pin under normal operating conditions. When
EN is high, OUT turns on; when EN is low, OUT turns off. For
automatic startup, EN can be tied to IN.
ADJUSTABLE OUTPUT VOLTAGE
(ADP1720 ADJUSTABLE)
The ADP1720 adjustable version can have its output voltage
set over a 1.225 V to 5.0 V range. The output voltage is set by
connecting a resistive voltage divider from OUT to ADJ. The
output voltage is calculated using the equation
VOUT = 1.225 V (1 + R1/R2) (1)
where:
R1 is the resistor from OUT to ADJ.
R2 is the resistor from ADJ to GND.
To make calculation of R1 and R2 easier, Equation 1 can be
rearranged as follows:
R1 = R2 [(VOUT /1.225) – 1] (2)
The maximum bias current into ADJ is 100 nA; therefore,
when less than 0.5% error is due to the bias current, use values
less than 60 kΩ for R2.
ADP1720
Rev. A | Page 11 of 16
APPLICATIONS INFORMATION
CAPACITOR SELECTION
Output Capacitor
The ADP1720 is designed for operation with small, space-saving
ceramic capacitors, but it functionswith most commonly used
capacitors as long as care is taken about the effective series
resistance (ESR) value. The ESR of the output capacitor affects
stability of the LDO control loop. A minimum of 1 μF capacitance
with an ESR of 500 mΩ or less is recommended to ensure sta-
bility of the ADP1720. Transient response to changes in load
current is also affected by output capacitance. Using a larger
value of output capacitance improves the transient response of
the ADP1720 to large changes in load current. Figure 20 and
Figure 21 show the transient responses for output capacitance
values of 1 μF and 10 μF, respectively.
TIME (2µs/DIV)
10mV/DI
V
1
V
IN
= 12V
V
OUT
= 1.6V
C
IN
= 1µF
C
OUT
= 1µF
LOAD STEP FRO M 2.5mA T O 47. 5mA
06111-020
Figure 20. Output Transient Response, 1 μF
TIME (2µs/DIV)
10mV/DI
V
1
V
IN
= 12V
V
OUT
= 1. 6V
C
IN
= 10µ F
C
OUT
= 10µ F
LO AD STE P FROM 2.5mA T O 47.5mA
1-0210611
Figure 21. Output Transient Response, 10 μF
Input Bypass Capacitor
Connecting a 1 μF capacitor from IN to GND reduces the cir-
cuit sensitivity to printed circuit board (PCB) layout, especially
when encountering long input traces or high source impedance.
If greater than 1 μF of output capacitance is required, it is
recommended that the input capacitor be increased to match it.
Input and Output Capacitor Properties
Any good quality ceramic capacitors can be used with the
ADP1720, as long as they meet the minimum capacitance and
maximum ESR requirements. Ceramic capacitors are manufac-
tured with a variety of dielectrics, each with different behavior
over temperature and applied voltage. Capacitors must have a
dielectric adequate to ensure the minimum capacitance over
the necessary temperature range and dc bias conditions. X5R
or X7R dielectrics with a voltage rating of 6.3 V or 10 V are
recommended for the output capacitor. X5R or X7R dielectrics
with a voltage rating of 50 V or higher are recommended for the
input capacitor.
Y5V and Z5U dielectrics are not recommended, due to their
poor temperature and dc bias characteristics.
CURRENT LIMIT AND THERMAL OVERLOAD
PROTECTION
Current limit and thermal overload protection circuits on the
ADP1720 protect the part from damage caused by excessive power
dissipation. The ADP1720 is designed to current limit when
the output load reaches 90 mA (typical). When the output
load exceeds 90 mA, the output voltage is reduced to maintain
a constant current limit.
Thermal overload protection is included, which limits the junction
temperature to a maximum of 150°C (typical). Under extreme
conditions (that is, high ambient temperature and power dissipa-
tion), when the junction temperature starts to rise above 150°C,
the output is turned off, reducing the output current to zero.
When the junction temperature drops below 135°C, the output is
turned on again, and output current is restored to its nominal value.
Consider the case where a hard short from OUT to GND occurs.
At first, the ADP1720 current limits so that only 90 mA is
conducted into the short. If self-heating of the junction is
great enough to cause its temperature to rise above 150°C,
thermal shutdown activates, turning off the output and
reducing the output current to zero. As the junction
temperature cools and drops below 135°C, the output turns on
and conducts 90 mA into the short, again causing the junction
temperature to rise above 150°C. This thermal oscillation
between 135°C and 150°C causes a current oscillation between
90 mA and 0 mA, which continues as long as the short
remains at the output.
Current and thermal limit protections are intended to protect
the device against accidental overload conditions. For reliable
operation, device power dissipation must be externally limited
so that junction temperatures do not exceed 125°C.
ADP1720
Rev. A | Page 12 of 16
THERMAL CONSIDERATIONS
To guarantee reliable operation, the junction temperature of the
ADP1720 must not exceed 125°C. To ensure the junction tem-
perature stays below this maximum value, the user needs to be
aware of the parameters that contribute to junction temperature
changes. These parameters include ambient temperature, power
dissipation in the power device, and thermal resistances between
the junction and ambient air (θJA). The θJA number is dependent
on the package assembly compounds used and the amount of
copper to which the GND pins of the package are soldered on the
PCB. Table 5 shows typical θJA values of the 8-lead MSOP package
for various PCB copper sizes.
Table 5.
Copper Size (mm2) θJA (°C/W)
01 118
50 99
100 77
300 75
500 74
140
0028
V
IN
– V
OUT
(V)
T
J
(°C)
1 Device soldered to minimum size pin traces.
The junction temperature of the ADP1720 can be calculated
from the following equation:
TJ = TA + (PD × θJA) (3)
where:
TA is the ambient temperature.
PD is the power dissipation in the die, given by
PD = [(VIN – VOUT) × ILOAD] + (VIN × IGND) (4)
where:
ILOAD is the load current.
IGND is the ground current.
VIN and VOUT are input and output voltages, respectively.
Power dissipation due to ground current is quite small and
can be ignored. Therefore, the junction temperature equation
simplifies to the following:
TJ = TA + {[(VIN – VOUT) × ILOAD] × θJA} (5)
As shown in Equation 5, for a given ambient temperature,
input-to-output voltage differential, and continuous load
current, there exists a minimum copper size requirement for
the PCB to ensure that the junction temperature does not rise
above 125°C. Figure 22 to Figure 27 show junction temperature
calculations for different ambient temperatures, load currents,
VIN to VOUT differentials, and areas of PCB copper.
120
100
80
60
40
20 1mA
5mA 10mA
20mA 30mA
40mA 50mA
(LOAD CURRENT )
MAX T
J
(DO NO T O PERAT E ABOV E TH I S POINT)
06111-022
4 8 12 16 20 24
Figure 22. 300 mm2 of PCB Copper, TA = 25°C
140
002
V
IN
– V
OUT
(V)
T
J
(°C)
8
120
100
80
60
40
20 1mA
5mA 10mA
20mA 30mA
40mA 50mA
(LOAD CURRENT )
4 8 12 16 20 24
MAX T
J
(DO NO T O PERAT E ABOV E TH I S POINT)
06111-023
Figure 23. 100 mm2 of PCB Copper, TA = 25°C
140
002
V
IN
– V
OUT
(V)
8
(°C)T
J
120
100
80
40
20
60
1mA
5mA 10mA
20mA 30mA
40mA 50mA
(LOAD CURRENT )
4 8 12 16 20 24
MAX T
J
(DO NO T O PERAT E ABOV E TH I S POINT)
1-0240611
Figure 24. 0 mm2 of PCB Copper, TA = 25°C
ADP1720
Rev. A | Page 13 of 16
140
002
V
IN
– V
OUT
(V)
8
T
J
(°C)
120
100
80
60
40
20 1mA
5mA 10mA
20mA 30mA
40mA 50mA
(LOAD CURRENT )
4 8 12 16 20 24
MAX T
J
(DO NO T O PERAT E ABOV E TH I S POINT)
111-02506
Figure 25. 300 mm2 of PCB Copper, TA = 50°C
140
0028
V
IN
– V
OUT
(V)
T
J
(°C)
120
100
80
60
40
20 1mA
5mA 10mA
20mA 30mA
40mA 50mA
(LOAD CURRENT )
4 8 12 16 20 24
MAX T
J
(DO NO T O PERAT E ABOV E TH I S POINT)
06111-026
Figure 26. 100 mm2 of PCB Copper, TA = 50°C
140
002
V
IN
– V
OUT
(V)
T
J
(°C)
8
120
100
80
60
40
20 1mA
5mA 10mA
20mA 30mA
40mA 50mA
(LOAD CURRENT )
4 8 12 16 20 24
MAX T
J
(DO NO T O PERAT E ABOV E TH I S POINT)
06111-027
Figure 27. 0 mm2 of PCB Copper, TA = 50°C
ADP1720
Rev. A | Page 14 of 16
PRINTED CIRCUIT BOARD LAYOUT
CONSIDERATIONS
R1
C2C1
ADP1720
IN OUT
GND (TOP )
R2 EN
GND (BOTTOM )
06111-028
Heat dissipation from the package can be improved by increasing
the amount of copper attached to the pins of the ADP1720. How-
ever, as can be seen from Table 5, a point of diminishing returns
eventually is reached, beyond which an increase in the copper
size does not yield significant heat dissipation benefits.
Place the input capacitor as close as possible to the IN and GND
pins. Place the output capacitor as close as possible to the OUT
and GND pins. Use of 0402 or 0603 size capacitors and resistors
achieves the smallest possible footprint solution on boards
where area is limited.
Figure 28. Example PCB Layout
ADP1720
Rev. A | Page 15 of 16
COMPLIANT TO JEDEC STANDARDS MO-187-AA
OUTLINE DIMENSIONS
0.80
0.60
0.40
8°
0°
4
8
1
5
PIN 1 0.65 BSC
SEATING
PLANE
0.38
0.22
1.10 MAX
3.20
3.00
2.80
COPLANARITY
0.10
0.23
0.08
3.20
3.00
2.80
5.15
4.90
4.65
0.15
0.00
0.95
0.85
0.75
Figure 29. 8-Lead Mini Small Outline Package [MSOP]
(RM-8)
Dimensions shown in millimeters
ORDERING GUIDE
Model Temperature Range
Output
Voltage (V) Package Description Package Option Branding
ADP1720ARMZ-5-R71
–40°C to +125°C 5 8-Lead MSOP RM-8 L30
ADP1720ARMZ-3.3-R71
–40°C to +125°C 3.3 8-Lead MSOP RM-8 L2Z
ADP1720ARMZ-R71
–40°C to +125°C 1.225 to 5 8-Lead MSOP RM-8 L2M
ADP1720-5-EVALZ1
5 Evaluation Board
ADP1720-3.3-EVALZ1
3.3 Evaluation Board
ADP1720-EVALZ1
1.225 to 5 Evaluation Board
1 Z = RoHS Compliant Part.
ADP1720
Rev. A | Page 16 of 16
NOTES
©2007 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D06111-0-7/07(A)
