Preliminary
RT9172
3A Fixed Output Voltage LDO Regulator
General Description
The RT9172 series of low-dropout linear regulators
operate from a +2.25V to +6.0V input supply. A wide
range of preset output voltage options is available.
These low dropout linear regulators respond very
fast to step changes in load, which are suitable for
low
voltage
microprocessor
applications.
The
RT9172 uses an internal PMOS as the pass device,
which does not cause extra GND current in heavy
load and dropout condition. The shutdown mode of
low operation current makes the IC suitable for
power-saving systems. The other features include
current limiting and over temperature protection.
Features
Low Dropout Voltage
Low Ground Pin Current
Load Regulation of 0.4% at 3A
0.5µA Quiescent Current in Shutdown Mode
µ
Guaranteed Output Current of 3A DC
Available in TO-263 and TO-220 Packages
Output Voltage Accuracy
±
1.5%
Error Flag Indicates Output Status
Sense Option Improves Better Load Regulation
Extremely Low Output Capacitor Requirements
Over-temperature/Over-current Protection
Ordering Information
RT9172 -
Package type
T5 : TO-220-5
M5 : TO-263-5
T : TO-220
M : TO-263
G : SOT-223
Operating temperature range
C: Commercial standard
Output voltage
15 : 1.5V
16 : 1.6V
:
32 : 3.2V
33 : 3.3V
S: Pin out exchange
N : Pin 5 bond sense
F : Pin 5 bond flg
Applications
Microprocessor Power Supplies
GTL, GTL+, BTL, and SSTL Bus Terminators
Power Supplies for DSPs
SCSI Terminator
Post Regulators
High Efficiency Linear Regulators
Battery Chargers
Other Battery Powered Applications
Pin Configurations
Part Number
RT9172-
CT
Pin Configurations
TOP VIEW
1. VIN
2. GND (TAB)
3. VOUT
1 2 3
(Plastic TO-220)
RT9172-
CM
TOP VIEW
1. VIN
2. GND (TAB)
3. VOUT
1
2
3
(Plastic TO-263)
RT9172-
CG
1
2
3
TOP VIEW
1. VIN
2. GND (TAB)
3. VOUT
(Plastic SOT-223)
To be continued
DS9172-03 April 2002
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1
RT9172
Absolute Maximum Ratings
Input Voltage
Power Dissipation
ESD Rating
Storage Temperature Range
Lead Temperature (Soldering, 5 sec.)
Package Thermal Resistance
TO-263,
θ
JC
TO-263,
θ
JA
TO-220,
θ
JC
TO-220,
θ
JA
SOT-223,
θ
JC
SOT-223,
θ
JA
Junction Temperature Range
Preliminary
6V
Internally Limited
3 kV
−65°C
to 150°C
260°C
8°C/W
19.4°C/W
8°C/W
62°C/W
15°C/W
60°C/W
-40°C to +125°C
Electrical Characteristics
(Limits in standard typeface are for T
A
= 25°C, unless otherwise specified: V
IN
= V
O(NOM)
+ 1.0V, I
L
= 10mA, C
OUT
=
10µF (Ceramic), V
EN
= V
IN
)
Parameter
Output Voltage Tolerance
Input Voltage Range
Line Regulation
Load Regulation
Dropout Voltage
Quiescent Current
Shutdown Supply Current
Peak Output Current
Short Circuit Protection
Current Limit
Over Temperature Protection
Shutdown Threshold
Thermal Shutdown Hysteresis
Shutdown Function
EN Pin Shutdown Threshold
EN Input Current
FLG Pin Leakage Current
FLG Pin Sink Current
I
LEAKAGE
V
FLG
= 0.5V
V
EN
Output = High
Output = Low
V
EN
= V
IN
1.2
--
--
--
2
V
IN
0
0.1
1
--
--
0.4
--
--
--
V
nA
nA
mA
T
SD
Guaranteed by design
Guaranteed by design
--
--
170
10
--
--
°C
°C
I
LIMIT
3.5
5
--
A
V
IN
∆V
LINE
∆V
LOAD
V
DROP
I
Q
I
GSD
I
O(PEAK)
V
EN
= 0V
V
OUT
+ 0.4V
<
V
IN
<
6.0V
Note 1
Note 2
I
L
= 300mA
I
L
= 3A
Symbol
Test Conditions
Min
-1.5
2.25
--
--
--
--
--
--
--
3.5
Typ
0
--
0.35
0.4
0.1
50
400
1.2
0.5
5
Max
+1.5
6
0.8
1
0.3
70
700
3
5
--
Units
%
V
%
%
mV
mA
µA
A
Note 1: RT9172-CX, RT9172F-XXCX5, 10mA < I
L
< 3A
Note 2: RT9172S-XXCX5, RT9172N-XXCX5, 10mA < I
L
< 3A
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4