Document
RT9176
1.5A Fixed and Adjustable Low Dropout Positive Voltage Regulators
General D escription
The RT9176 series of high perf ormance positive voltage regulators is designed or fa pplication s requiring low dropout performance at fully rated current. Additionally, the R T9176 series provides excellent regulation over variations in line and loa d. Outsta nding feature s include low dropout performance at rated current, fa st tra nsient re sponse, internal current-li miting, and thermal-shutdown prote ction of the output device. The RT9176 series of three terminal regulators of fers f ixed a nd a djustable voltage option s available in spa ce-saving SOT -223, TO-252, and TO-263 packages.
Feature s
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Low Dropout Performance, 1.5V Max. Full Current Rating Over Line a nd Temperature Fast Transient Response ± 2% Output Voltage Accuracy 1.5V, 1.8V, 2.5V, 2.85V, 3.3V, a nd 3.5V Fixed a nd Adjustable Output Voltage SOT-223, TO-252, and TO-263 Packages RoHS Compliant and 100% Lead (Pb)-Free
Applications
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Active SCSITermination Low Voltage Microcontrollers Switching Power Supply Post-Regulator
Ordering Information
RT9176Package Type G : SOT-223 L: TO-252 M : TO-263
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Pin ConFiguration s
(TOP VIEW)
3 2 1 VIN VOUT (TAB) ADJ/GND
Operating Temperature Range C : Commercial Standard P : Pb Free with Commercial Standard Output Voltage Default : Adjustable 15 : 1.5V 18 : 1.8V 25 : 2.5V 28 : 2.85V 33 : 3.3V 35 : 3.5V
Note : RichTek Pb-free products are : −RoHS compliant and compatible with the current requirements of IPC/JEDEC J-ST D-020. −Suitable for use in SnPb or Pb-free soldering processes. −100%matte tin (Sn) plating.
SOT-223
3 2 1
VIN VOUT (TAB) ADJ/GND
TO-252
3 2 1
VIN VOUT (TAB) ADJ/GND
TO-263
DS9176-09 March 2005
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http://www.Datasheet4U.com/
RT9176
Typical Application Circuit
RT9176 VIN = 5V + C1 10uF VIN ADJ VOUT VREF IADJ R1 133 1% R2 232 1% + VOUT = 3.45V
C2 10uF
Tantalum
V OUT = V REF (1+ (1) C1 needed if device is far from filter capacitors. (2) C2 required for stability.
R2 R1
) + I ADJ R 2
Figure 1. Adjustable Voltage Regulator
VIN = 5V +
GND
+
VIN
RT9176-33 VOUT GND +
VOUT 3.3V C2 10uF Tantalum
C1 10uF IQ
(1) C1 needed if device is far from filter capacitors. (2) C2 required for stability.
Figure 2. Active SCSI Bus Terminator
RT9176-28 VIN VOUT
18 - 27 Lines
+
10uF IQ
22uF
Figure 3. Fixed Voltage Regulator
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DS9176-09 March 2005
http://www.Datasheet4U.com/
RT9176
Function Block Diagram
VIN
S.O.A. Current Limiting Amplifier LIMIT VOUT SENSE Thermal Overload
Voltage Regulation Amplifer
VREF
ADJ/GND
Functional Pin Description
Pin Name ADJ/GND VOUT VIN Power Pin Function Adjust Output Voltage or GND Output Voltage Input
DS9176-09 March 2005
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http://www.Datasheet4U.com/
RT9176
Absolute Maximum Ratings
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(Note 1)
Supply Input Voltage --------------------------------------------------------------------------------------------------15V Power Dissipation, PD @ TA = 25°C SOT-223 -----------------------------------------------------------------------------------------------------------------0.740W TO-252-------------------------------------------------------------------------------------------------------------------1.471W TO-263-------------------------------------------------------------------------------------------------------------------2.222W Package Thermal Resistance (Note 6) SOT-223, θJA ------------------------------------------------------------------------------------------------------------135°C/W SOT-223, θJC -----------------------------------------------------------------------------------------------------------19°C/W TO-252, θJA -------------------------------------------------------------------------------------------------------------68° C/W TO-252, θJC -------------------------------------------------------------------------------------------------------------7.5° C/W TO-263, θJA -------------------------------------------------------------------------------------------------------------45° C/W TO-263, θJC -------------------------------------------------------------------------------------------------------------7.8° C/W Lead Temperature (Soldering, 10 se c.) ---------------------------------------------------------------------------260° C Junction T emperature-------------------------------------------------------------------------------------------------150°C Storage T emperatureRange ----------------------------------------------------------------------------------------−65°C to 150°C ESD Susceptibility (Note 2) HBM (Human Body Mode) ------------------------------------------------------------------------------------------8kV MM (Machine Mode)--------------------------------------------------------------------------------------------------750V (Note 3)
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Recommended Operating Condition s
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Supply Input Voltage -------------------------------------------------------.