IMP IMP37

IMP3 7
POWER MANAGEMENT
Low Dropout Positive
Voltage Regulators
Key Features
◆ Low Dropout Voltage
– 0.8V maximum at 100mA
– 0.95V maximum at 800mA
– 20% lower dropout voltage than “1117”
LDO regulators
◆ Guaranteed Low Dropout Voltage at Multiple
Current Levels
◆ 1% Trimmed 2.5V, 3.0V and 3.3V Outputs
◆ Reduced Quiescent Current: 75µA Maximum
◆ Short Circuit and Thermal Protection
◆ Space Saving SOT-223 Surface Mount Package
◆ “1117” Pin Compatible
– 800mA
– 2.5V, 3.0V and 3.3V Output
The IMP37 series of Low Dropout (LDO) three-terminal voltage regulators feature guaranteed low dropout voltages at currents up to 0.8A. The
IMP37 regulator family dropout voltage is guaranteed to be 0.95V or
lower at 0.8A. At 100mA, the maximum dropout voltage is 0.8V.
Compared with “1117” type LDOs, the IMP37 has a 20% lower dropout
voltage.
Three fixed output voltages are offered: 2.5V, 3.0V and 3.3V. Output voltages are factory trimmed to within 1% of the nominal value.
In addition to low dropout voltages, the IMP37 family features greatly
reduced quiescent operating current. The 75µA maximum specification
represents an over 100 times improvement over competitive devices.
Applications
Devices are short circuit protected, and a thermal protection circuit shuts
the regulator off should the junction temperature exceed 165°C.
◆
◆
◆
◆
◆
◆
The IMP37 is available in low-profile plastic SOT-223 and TO-263
packages and are pin compatible with fixed “1117” devices.
High-efficiency linear power supplies
Post regulator for switching supplies
5V to 3.3V linear regulators
USB hubs
Battery chargers
Routers, ISDN/DSL modems
Block Diagram
Input
3
RCS
2
Out
(Tab)
IMP37
Error
Amp
+
+
–
Current
Limit
–
Thermal
Protection
+
Ref
–
1
GND
© 1999 IMP, Inc.
408-432-9100/www.impweb.com
37_01.eps
1
IMP3 7
Pin Configuration
SOT-223
TO-263
INPUT
3
IMP37
TAB IS VOUT
2
OUT
1
GND
IMP37
TAB IS VOUT
3
INPUT
2
OUT
1
GND
37_04.eps
37_05.eps
Front View
Front View
Pin Descriptions
Package Marking Code
Pin Number
Name
Function
1
GND
Ground Pin
2
OUT
Output Voltage
IMP37-25JST
SOT-223
3725
Input Voltage
IMP37-30JST
SOT-223
3730
IMP37-33JST
SOT-223
3733
IMP37-25JCM
TO-263
3725JCM
IMP37-30JCM
TO-263
3730JCM
IMP37-33JCM
TO-263
3733JCM
3
INPUT
TAB
TAB
Part Number
Output Voltage
37_Table03.eps
Package
Device
Marking
37_Table05.eps
Ordering Information
Output Options
Part Ordering Number
Voltage
Maximum
Quiescent Current
Dropout Voltage at
800mA
SOT-223
Package
TO-263
Package
2.5V
75µA
0.95V
IMP37-25JST
IMP37-25JCM
3.0V
75µA
0.95V
IMP37-30JST
IMP37-30JCM
3.3V
75µA
0.95V
IMP37-33JST
IMP37-33JCM
37_t06.eps
Note: Tape and reel shipping is available for the SOT-223 and TO-263 packages. Append the TAPE AND REEL designation “/T” to the ordering
part number for tape and reel devices. For example, the IMP37-25JST/T is a 2.5V SOT-223 packaged device shipped in reels.
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© 1999 IMP, Inc.
IMP3 7
Absolute Maximum Ratings
Input Voltage . . . . . . . . . . . . . . . . . . . . . . . . . 7V
Operating Junction Temperature . . . . . . . . . 0°C to 150°C
Storage Temperature Range . . . . . . . . . . . . . –65°C to +150°C
Lead Temperature (Soldering) . . . . . . . . . . . . . 300°C for 10 seconds
These are stress ratings only and functional operation is not implied.
Exposure to absolute maximum ratings for prolonged time periods may
affect device reliability. All voltages are with respect to ground.
Electrical Characteristics
Specifications apply over the junction operating temperature range of TJ = 0°C to +125°C unless otherwise noted.
Parameter
Output Voltage
Symbol Suffix Conditions
VOUT
Line Regulation
(Note 1)
Line Regulation
(Note 1)
Min
Typ
Max
Units
IOUT = 10mA, VIN = 4.85V, TJ = 25°C
10mA ≤ IOUT ≤ IMAX, 4.25V ≤ VIN ≤ 5.5V
2.475
2.5
2.525
V
2.45
2.5
2.55
–30
IOUT = 10mA, VIN = 5V, TJ = 25°C
2.97
3.00
3.03
2.94
3.00
3.06
–33
10mA ≤ IOUT ≤ IMAX, 4.75V ≤ VIN ≤ 5.5V
IOUT = 10mA, VIN = 5V, TJ = 25°C
3.267
3.30
3.333
3.235
3.30
3.365
–25
10mA ≤ IOUT ≤ IMAX, 4.75V ≤ VIN ≤ 5.5V
IOUT = 10mA, 4.25V ≤ (VIN) ≤ 5.5V
12
19
–25
–30
IOUT = 10mA, 4.5V ≤ VIN ≤ 5.5V
12
19
–33
IOUT = 10mA, 4.5V ≤ VIN ≤ 5.5V
IOUT = 10mA, 4.25V ≤ (VIN) ≤ 5.5V, TA = 25°C
12
19
2.8
4.3
TA = 25°C
2.8
4.3
TA = 25°C
2.8
4.3
VIN = 4.25V, 5mA ≤ IOUT ≤ 800mA
VIN = 4.75V, 5mA ≤ IOUT ≤ 800mA
25
30
25
30
VIN = 4.75V, 5mA ≤ IOUT ≤ 800mA
IOUT = 100mA
25
30
–25
–30
–33
Load Regulation
(Note 1)
–25
–30
–33
Dropout Voltage
(Note 2)
Current Limit
–xx
IOUT(MAX)
–xx
TJ = 25°C
IQ
–xx
800
VIN ≤ 6V
TA = 25°C, 30ms Pulse
Ripple Rejection
fRIPPLE = 120Hz, VIN = 5V, TA = 25°C
VRIPPLE = 1Vp-p, ILOAD= 10mA
Temperature Stability
Long Term Stability
TA = 125°C, 1000 Hrs
RMS Output Noise
(% of VOUT), 10Hz ≤ f ≤ 10kHz, TJ = 25°C
Junction-to-Case at TAB (TO-223)
Junction-to-Case at TAB (TO-263)
950
408-432-9100/www.impweb.com
mV
V
1200
mA
5.0
mA
36
75
µA
0.01
0.1
%/W
51
54
dB
0.5
%
0.3
%
0.003
%
15
°C/W
10
Notes: 1. See thermal regulation specification for changes in output voltage due to heating effects. Load regulation and line regulation
are measured with low duty cycle pulse testing to maintain a constant junction temperature.
2. Dropout voltage is specified over the full output current range. Dropout voltage is defined as the minimum input/output
differential measured at the specified output current.
3. Minimum load current is defined as the minimum output current required to maintain regulation.
© 1999 IMP, Inc.
mV
0.95
–xx
Thermal Regulation
Thermal Resistance
0.8
IOUT = 800mA
Minimum Load Current
Quiescent Current
IOUT = 10mA, 4.5V ≤ VIN ≤ 5.5V,
IOUT = 10mA, 4.5V ≤ VIN ≤ 5.5V,
mV
37_t07.eps
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IMP3 7
Application Information
The IMP37 voltage regulator ICs offer self-protection features
which include short-circuit current protection and automatic thermal
shutdown (for junction temperature above 165°C).
Circuit Stability
Like all regulators, an output filter capacitor is required for circuit stability. Besides smoothing the output, the output capacitor
“completes” the regulator’s frequency compensation. The ESR of the
output capacitor should be less than 0.5Ω. Low ESR capacitors are
preferred.
Table 1 shows recommended minimum capacitance values for both
aluminum and tantalum capacitors. Larger values of output capacitance do not cause stability problems.
Table 1. Recommended Output Bypass Capacitors
Thermal Management
The maximum operating junction temperature for the IMP37 devices
is 150°C. The junction temperature can be calculated when the
power dissipation and ambient temperature are known with this
equation: TJ = TA + (PD x ΘJA).
The thermal resistance from juntion-to-ambient (ΘJA) is the sum of
the three thermal resistances:
ΘJA = ΘJT + ΘTS + ΘSA
Where ΘJT = Junction-to-Tab thermal resistance
ΘTS = Tab-to-Heat Sink thermal resistance
ΘSA = Heat Sink-to-Air thermal resistance
Table 2. Thermal Resistance of Packages
Output Bypass Capacitor (ESR < 0.5Ω)
10µF Tantalum, 100µF Aluminum
Thermal Resistance
Package Type
An input bypass capacitor is recommended. A 10µF or larger tantalum capacitor is suitable for most applications.
Junction to Tab, ΘJT
SOT-223
15°C/W
TO-263
10°C/W
The IMP37 series devices have thermal limiting circuitry to protect
the device from over current. For continuous operation, the maximum junction temperature rating must not be exceeded.
IMP37
IN
VIN
*
+
3.3V
OUT
GND
+
**
* Min. 15µF Tantalum or 100µF Aluminum.
Capacitor May Be Increased Without Limit.
** 10µF Tantalum or 100µF Aluminum
37_02.eps
Figure 1. Fixed 3.3V Regulator
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© 1999 IMP, Inc.
IMP3 7
Package Dimensions
Plastic SOT-223 (4-Pin)
Inches
Min
B
Millimeters
Max
Min
Max
Plastic SOT-223 (4-Pin)*
E
H
e
S
Q1
D
Q
A
B1
A1
Q2
e1
C
SOT-223 (4-Pin).eps
A
C2
L2
D
L
L1
0° - 8°
B2
e
B
0.067
0.060
0.004
0.0008
0.124
0.116
0.033
0.026
0.014
0.010
0.264
0.248
0.0905 NOM
0.181 NOM
0.146
0.130
0.287
0.264
0.041
0.033
0.051
0.043
10° MAX
16°
10°
16°
10°
1.70
0.10
3.15
0.85
0.35
6.70
1.50
0.02
2.95
0.65
0.25
6.30
2.30 NOM
4.50 NOM
3.70
7.30
1.05
1.30
3.30
6.70
0.85
1.10
10° MAX
16°
16°
10°
10°
TO-263 (3-Pin)**
TO-263 (3-Pin)
E
A
A1
B
B1
C
D
e
e1
E
h
S
t
Q
Q1
Q2
C
TO-263 (3-Pin).eps
A
0.160
0.190
B
0.020
0.039
B2
0.045
0.055
C
0.018
0.029
C2
0.045
0.055
D
0.340
0.380
E
0.380
0.405
e
0.100 BSC
L
0.575
0.625
L1
0.090
0.110
L2
———
0.055
* JEDEC Drawing TO-261AA
** JEDEC Drawing TO-263AA
♦
Add /T to Part Number for Tape and Reel.
37_Table04.eps
© 1999 IMP, Inc.
408-432-9100/www.impweb.com
5
IMP3 7
IMP, Inc.
Corporate Headquarters
2830 N. First Street
San Jose, CA 95134-2071
Tel: 408-432-9100
Tel: 800-438-3722
Fax: 408-434-0335
Fax-on-Demand: 1-800-249-1614 (USA)
Fax-on-Demand: 1-303-575-6156 (International)
e-mail: [email protected]
http://www.impweb.com
The IMP logo is a registered trademark of IMP, Inc.
All other company and product names are trademarks of their respective owners.
© 1999 IMP, Inc.
Printed in USA
Publication #: 8002
Revision:
C
Issue Date:
07/22/99
Type:
Preliminary