1A Ultra Low Dropout Regulator

Transcription

1 1A Ultra Low Dropout Regulator Description The is a high performance positive voltage regulator designed for use in applications requiring very low input voltage and very low dropout voltage at up to 1A. The provides current limiting and thermal shutdown function which protects the excessive heating due to high current and high junction temperature. The is available in the SOT-3-5 and TDFN- packages. Features 300mV Dropout at 1A current. Power MOSFET Integrated Low Output Voltage Offset Current Limiting Protection Thermal Shutdown Protection Adjusted Output by External Resistors Shutdown for Standby or Suspend Mode RoHS Compliant Applications Motherboard Applications NoteBook PC Applications Set Top Boxes Pin Assignments S5 Package (SOT-3-5) VCNTL VIN Ordering Information TR: Tape/Reel G: Green Package Type S5: SOT-3-5 WD: TDFN-(mmXmm) VOUTGND REFEN WD Package (TDFN- ) (xmm) SOT-3-5 Marking Part Number Product Code S5GTR U8= TDFN-(xmm) Marking Part Number WDGTR Product Code U9G Figure 1. Pin Assignment of (Top View) 1

2 Typical Application Circuit R V D OUT = VREFEN = VIN RU + RD Figure. Typical Application Circuit of Functional Pin Description Pin Name VIN GND VCNTL REFEN Pin Function Power input pin. VIN is the input power supply used to create the external reference voltage for regulating VOUT. VIN sources current to VOUT by upper NMOS. Common ground pin. Power input pin. The VCNTL power supplies the internal control circuitry and gate drive voltage. Chip enable, and input reference voltage pin. VOUT Regulator output pin. VOUT voltage tracks the REFEN voltage.

3 Block Diagram VCNTL VIN REFEN + - Error Amp VOUT Current Limit & Thermal Shutdown GND Absolute Maximum Ratings Figure 3. Block Diagram of VIN to GND V VCNTL to GND V Power (P D ): 1.5W SOT W TDFN- (mxm) W Package Thermal Resistance (θ JA ): SOT /W TDFN-(mXm) /W C Storage Temperature Range C to 150 C Lead Temperature (Soldering, 10sec.) C Note1:Stresses beyond those listed under Absolute Maximum Ratings" may cause permanent damage to the device. Recommended Operating Conditions Input Voltage (V IN ) V to 5.5 V Input Voltage ( ) V to 5.5V Operating Temperature Range (T OPR ) ºC to + 85ºC 3

4 Electrical Characteristics (, V IN =1.5V/1.8V/.5V, V REFEN =0.5*V IN, C OUT =10uF, T A =5 C, unless otherwise specified) Parameter Symbol Test Conditions Min Typ Max Units INPUT Operation Voltage Range V Quiescent Current I CNTL No Load ma Shutdown Current I SD V REFEN <0.V 5 30 ua OUTPUT VOLTAGE Output Offset Voltage V OS No Load, (V REFEN -V OUT ) mv Load Regulation (Note) Δ V LOAD I OUT = 0 to 1A 0 mv Dropout Voltage (Note3) PROTECTION VD, I OUT = 1A (for TDFN package) 300, I OUT = 0.3A 100 Current Limit I LIM.0.5 A mv Thermal Shutdown Temperature (Note) T SD 170 C Δ T SD Hysteresis 35 C SHUTDOWN CONTROL Enable High Level V REF-H 0. V Shutdown Low Level V REF-L 0. V Note:Load regulation and dropout voltage are measured at a constant junction temperature by using a 0ms low duty cycle current pulse. Note3:The dropout voltage is defined as V IN -V OUT, which is measured when V OUT drops % of its normal value with the specified output current. Note:The specification is guaranteed by design, not production tested.

5 Typical Performance Curves Turn-On Threshold Voltage (V) Turn-OFF Threshold Voltage (V) Figure. Turn-On Threshold Voltage vs. 0.0 Figure 5. Turn-Off Threshold Voltage vs. 8 V OUT =1.5V 8 V OUT =0.9V Output Offset V OUT -V REFEN (mv) Output Offset V OUT -V REFEN (mv) Figure. Output offset (V OUT -V REFEN ) vs. -8 Figure 7. Output offset (V OUT -V REFEN ) vs. 5 Sourcing, V IN =.5V V IN =.5V, V REFEN =1.5V Current Limit (A) 3 1, V IN =.5V, V IN =1.8V, V IN =1.8V 0 Juncition Temperature ( 0 C) Figure 8. Current Limit vs. Figure9. Output Short-Circuit Protection 5

6 Outline Information SOT-3-5 Package (Unit: mm) SYMBOLS DIMENSION IN MILLIMETER UNIT MIN MAX A A A B D E E e e L Note:Followed From JEDEC MO-178-C. TDFN- mm mm Package (Unit: mm) SYMBOLS DIMENSION IN MILLIMETER UNIT MIN MAX A A A D E a b e D E Note:Followed From JEDEC MO-9-C Life Support Policy Fitipower s products are not authorized for use as critical components in life support devices or other medical systems.