www.fairchildsemi.com FAN1538 Dual Channel 1A Low Dropout Linear Regulator with UVLO and Soft-start Features General Description • • • • • • The FAN1538 provides two output voltages: a fixed 3.3V ouput and either a fixed 2.5V or adjustable output with 1A output current capability. Refer to Ordering Information for details. Two independent outputs Load regulation: 0.05% typical Under-voltage lockout and softstart Over Temperature protection T0-252 DPAK, 5-lead SPAK packages Fixed 3.3V and adjustable or fixed 2.5V output Current limit protects against short circuit currents and on chip over temperature circuitry limits the maximum die temperature. Applications • • • • Hard Disk Drives, CD-Roms Set-top Boxes ADSL line cards Motherboards with multiple supplies Under voltage lockout and softstart circuitry protects against unregulated output voltages when the input voltage is below specification. Block Diagram FAN1538A V1 VIN = 5V + 3.3V at 1.0A VIN 22µF 2.5V at 1.0A V2 NC GND + 22µF + 22µF FAN1538B V1 3.3V at 1.0A V2 1.5V at 1.0A VIN = 5V 22 µF GND FB R1 250 22µF 22µF R2 1250 V2 = VREF (1 + R1/R2) REV. 1.0.2 12/17/03 FAN1538 PRODUCT SPECIFICATION Pin Assignments 4 5 V1 3 V2 2 FB 1 GND 5 VIN 4 V1 NC 3 V2 2 GND 1 V1 4 5 V2 VIN V1 V2 5-Lead SPAK ΘJC=2°C/W FAN1538DB FRONT VIEW FAN1538DA FRONT VIEW VIN 1 2 3 4 5 FB GND 1 2 3 NC GND FAN1538PB FRONT VIEW VIN FAN1538PA FRONT VIEW 5-Lead SPAK ΘJC=2°C/W 5-Lead Plastic TO-252 DPAK ΘJC=3°C/W Tab is GND Pin Descriptions Pin Name SPAK DPAK VIN 1 Input supply voltage NC/FB 2 For V2 fixed, no connect. For V2 adjustable, feedback voltage. V1 4/5 Output #1 V2 5/4 Output #2 GND 3 Pin Function Ground Absolute Maximum Ratings Parameter VIN Storage Temperature Range Min. Max. 10 Units V -65 150 °C 300 °C Lead Soldering Temperature, 10 seconds Recommended Operating Conditions Parameter VIN Ambient Operating Temperature (TA) 2 Conditions Vin to GND Min. Typ. Max. 4.75 5 5.25 V 125 °C 0 Units REV. 1.0.2 12/17/03 PRODUCT SPECIFICATION FAN1538 Electrical Specifications (Operating Conditions: VIN = 5V, TJ=25°C unless otherwise specified) The • denotes specifications which apply over the full operating temperature range. Parameter Conditions V1 Output Voltage 10mA ≤ Iout ≤ 1A 4.50V ≤ VIN ≤ 7V 10mA ≤ Iout ≤ 1A 4.50V ≤ VIN ≤ 7V V2 Output Voltage (FAN1538A) V2 Minimum Output Voltage (FAN1538B) 10mA ≤ Iout ≤ 1A 4.50V ≤ VIN ≤ 7V Reference Voltage (FAN1538B) (FB) 10mA<Iout<1A 4.50V ≤ VIN ≤ 7V FB Pin Bias Current Min. Typ. Max. Units 3.234 3.200 3.300 3.300 3.366 3.400 V • 2.450 2.420 2.500 2.500 2.550 2.580 V • • 1.400 • 1.225 1.210 V 1.250 1.250 • 1.275 1.290 V 1 µA Line Regulation (Both Outputs) 4.50V ≤ VIN ≤ 7V Iout = 10mA • 0.005 0.5 % Load Regulation (Both Outputs) VIN=5.0V 10mA ≤ Iout ≤ 1A • 0.05 0.5 % Current Limit (Both Outputs) VIN = 5V Minimum Load Current (Both Outputs) 4.50V ≤ VIN ≤ 7V • Quiescent Current VIN = 5V • Ripple Rejection (Both Outputs) F = 60Hz, Cout = 22µF VIN = 5V, Iout =100mA 1.1 1.5 A 10 mA 6 15 60 mA dB Under-Voltage Lockout (See Diagram1) VIN Rising threshold • 3.4 3.8 4.2 V VIN Falling threshold • 3.0 3.3 3.6 V V1 & V2 delay start time VIN > UVLO Rising Threshold V1 softstart slew rate V2 softstart slew rate R1 = 1250 & R2 = 250 ohms V1 & V2 VIN < 3.4 150 µs 250 µs/V 550 µs/V • 0.5 V Thermal Shutdown Shut down Temperature 165 °C Thermal hysteresis 40 °C VIN VIN = 3.8V V3.3 Input Voltage VIN = 3.3V V1.5 150µs Time Diagram 1: UVLO and Softstart Timing REV. 1.0.2 12/17/03 3 PRODUCT SPECIFICATION FAN1538 Mechanical Dimensions TO-252 DPAK Package 6.00 MIN A 6.80 6.35 5.64 5.04 1.27 0.50 6.56 MIN 6.30 5.90 6.25 1.02 0.60 3.00 MIN C 1 3 2 1 5 4 1.27 (0.44) 0.57±0.07 1.27 1.00 3.81 0.69±0.15 1.27 0.25 M A M C LAND PATTERN RECOMMENDATION 5.08 B 2.40 2.18 0.60 0.40 (5.09) (4.05) 10.42 9.20 SEE DETAIL A 3 5 4 2 1 0.10 B GAGE PLANE 0.60 0.40 0.51 (1.54) NOTES: UNLESS OTHERWISE SPECIFIED 10° 0° 1.78 1.40 A) ALL DIMENSIONS ARE IN MILLIMETERS. B) THIS PACKAGE CONFORMS TO JEDEC, TO-252, ISSUE C, VARIATION AA, DATED NOV. 1999. 0.13 MAX (2.90) SEATING PLANE DETAIL A (ROTATED 90°) SCALE: 2X REV. 1.0.2 12/17/03 4 PRODUCT SPECIFICATION FAN1538 Mechanical Dimensions (continued) 5-Lead SPAK Inches Symbol Min. Millimeters Max. Min. Max. A B b1 b2 0.350 0.360 0.220 NOM 0.268 0.025 0.031 8.89 9.14 5.59 NOM 6.81 0.63 0.79 C c1 c2 D E e L L1 L2 L3 R α 0.080 0.070 0.040 0.050 0.010 NOM 0.295 NOM 0.365 0.375 0.067 2.03 1.78 1.02 1.27 0.25 NOM 7.49 NOM 9.27 9.52 1.72 0.410 0.031 0.350 10.41 0.79 8.89 0.420 0.041 0.360 0.310 0.320 0.010 NOM 0° 8° Notes: 1. All linear dimensions are in inches (millimeters). 2. This drawing is subject to change without notice. 3. The center lead is in electrical contact with the thermal tab. 4. Dimensions do not include mold protrusions, not to exceed 0.006 (0,15). Notes 10.67 1.04 9.14 7.87 8.13 0.25 NOM 0° 8° E C A c1 B c2 D L3 L 1 L2 Thermal Ta b (See Note 3) 5 Seating Plane b2 e b1 0.004 (0,10) 0.010 (0,25) M 0.005 (0.13) 0.001 (0.03) R L1 Gage Plane 3°–6° REV. 1.0.2 12/17/03 5 FAN1538 PRODUCT SPECIFICATION Ordering Information Part Number Voltage Option Package FAN1538DBX V1 = 3.3V, V2 = adj 5-Lead DPAK in Tape and Reel FAN1538PBX V1 = 3.3V, V2 = adj 5-Lead SPAK in Tape and Reel FAN1538DAX V1 = 3.3V, V2 = 2.5V 5-Lead DPAK in Tape and Reel FAN1538PAX V1 = 3.3V, V2 = 2.5V 5-Lead SPAK in Tape and Reel DISCLAIMER FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUCT OR CIRCUIT DESCRIBED HEREIN; NEITHER DOES IT CONVEY ANY LICENSE UNDER ITS PATENT RIGHTS, NOR THE RIGHTS OF OTHERS. LIFE SUPPORT POLICY FAIRCHILD’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and (c) whose failure to perform when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury of the user. 2. A critical component in any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. www.fairchildsemi.com 12/17/03 0.0m 005 Stock#DS30001538 2003 Fairchild Semiconductor Corporation