IMP37 IMP37

IMP377
IMP3
Data PCommunications
OWER M ANAGEMENT
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
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IMP3 7
Pin Configuration
SOT-223
TO-263
3
INPUT
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
3
INPUT
TAB
TAB
Part Number
IMP37-25JST
Package
Device
Marking
SOT-223
3725
Input Voltage
IMP37-30JST
SOT-223
3730
Output Voltage
IMP37-33JST
SOT-223
3733
IMP37-25JCM
TO-263
3725JCM
IMP37-30JCM
TO-263
3730JCM
IMP37-33JCM
TO-263
3733JCM
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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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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
–25
–30
–33
Line Regulation
(Note 1)
–25
Line Regulation
(Note 1)
Load Regulation
(Note 1)
Dropout Voltage
(Note 2)
Current Limit
IOUT(MAX)
Minimum Load Current
Quiescent Current
Min
Typ
Max
Units
IOUT = 10mA, VIN = 4.85V, TJ = 25°C
2.475
2.5
2.525
V
10mA ≤ IOUT ≤ IMAX, 4.25V ≤ VIN ≤ 5.5V
2.45
2.5
2.55
IOUT = 10mA, VIN = 5V, TJ = 25°C
2.97
3.00
3.03
10mA ≤ IOUT ≤ IMAX, 4.75V ≤ VIN ≤ 5.5V
2.94
3.00
3.06
IOUT = 10mA, VIN = 5V, TJ = 25°C
3.267
3.30
3.333
10mA ≤ IOUT ≤ IMAX, 4.75V ≤ VIN ≤ 5.5V
3.235
3.30
3.365
IOUT = 10mA, 4.25V ≤ (VIN) ≤ 5.5V
12
19
–30
IOUT = 10mA, 4.5V ≤ VIN ≤ 5.5V
12
19
–33
IOUT = 10mA, 4.5V ≤ VIN ≤ 5.5V
12
19
–25
IOUT = 10mA, 4.25V ≤ (VIN) ≤ 5.5V, TA = 25°C
2.8
4.3
–30
IOUT = 10mA, 4.5V ≤ VIN ≤ 5.5V, TA = 25°C
2.8
4.3
–33
IOUT = 10mA, 4.5V ≤ VIN ≤ 5.5V, TA = 25°C
2.8
4.3
–25
VIN = 4.25V, 5mA ≤ IOUT ≤ 800mA
25
30
–30
VIN = 4.75V, 5mA ≤ IOUT ≤ 800mA
25
30
–33
VIN = 4.75V, 5mA ≤ IOUT ≤ 800mA
25
30
–xx
IOUT = 100mA
0.8
IOUT = 800mA
0.95
–xx
800
TJ = 25°C
–xx
VIN ≤ 6V
Thermal Regulation
TA = 25°C, 30ms Pulse
Ripple Rejection
fRIPPLE = 120Hz, VIN = 5V, TA = 25°C
VRIPPLE = 1Vp-p, ILOAD= 10mA
Temperature Stability
51
V
5.0
mA
36
75
µA
0.01
0.1
%/W
54
dB
0.5
%
0.3
%
0.003
%
°C/W
Long Term Stability
TA = 125°C, 1000 Hrs
RMS Output Noise
(% of VOUT), 10Hz ≤ f ≤ 10kHz, TJ = 25°C
Thermal Resistance
Junction-to-Case at TAB (TO-223)
15
Junction-to-Case at TAB (TO-263)
10
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mV
mA
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.
b
mV
1200
950
–xx
IQ
mV
Low Dropout Voltage Regulators
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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.
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 1. Recommended Output Bypass Capacitors
Table 2. Thermal Resistance of Packages
Output Bypass Capacitor (ESR < 0.5Ω)
Thermal Resistance
10µF Tantalum, 100µF Aluminum
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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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
0.060
0.067
0.0008
0.004
0.116
0.124
0.033
0.026
0.014
0.010
0.264
0.248
0.0905 NOM
0.181 NOM
0.130
0.146
0.287
0.264
0.041
0.033
0.043
0.051
10° MAX
16°
10°
16°
10°
1.50
0.02
2.95
0.65
0.25
6.30
1.70
0.10
3.15
0.85
0.35
6.70
2.30 NOM
4.50 NOM
3.30
6.70
0.85
1.10
3.70
7.30
1.05
1.30
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
0.055
0.045
B2
0.029
0.018
C
C2
0.045
0.055
D
0.340
0.380
0.405
0.380
E
0.100 BSC
e
L
0.575
0.625
L1
0.090
0.110
0.055
———
L2
* JEDEC Drawing TO-261AA
** JEDEC Drawing TO-263AA
♦
Add /T to Part Number for Tape and Reel.
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© Daily Silver IMP
Low Dropout Voltage Regulators
5
IMP3 7
Daily Silver IMP Microelectronics Co.,Ltd
7 keda Road , Hi-Tech Park,
NingBo,Zhejiang, P.R.C.
Post Code : 315040
Tel:(086)-574-87906358
Fax:(086)-574-87908866
e-mail:[email protected]
Website:www.ds-imp.com.cn
b
The IMP logo is a registered trademark of Daily Silver IMP.
All other company and product names are trademarks of their respective owners.
2005 Daily Silver IMP
Revision : A
Issue Date: 08/08/05
Type: Product