Advanced Power Electronics Corp. APE8872 1.6X LINEAR FAN DRIVER WITH VO FULLY ON CONTROL FEATURES DESCRIPTION Low Dropout Voltage: [email protected] VO Follows 1.6 times of VSET FON Pin to Turn VO Fully On Stable with Low ESR Ceramic Capacitors Current-Limit and Thermal Shutdown Protection SOP-8 Pb-Free Package The APE8872 is a low dropout linear regulator which is designed to power a DC fan and delivers up to 500mA output current. The output voltage follows the 1.6 times of VSET voltage and typical dropout voltage is only 150mV (typical) at 500mA output current. The V SET voltage must be larger than 1V to guarantee V O 1.6 times of VSET. A FON pin turns VO output fully on when given low. The features of current limit (with fold back current) and over temperature protection protect the device against current over-loads and over temperature. The APE8872 is available in a SOP-8 package. TYPICAL APPLICATION U1 VIN=5V 2 VSET C1 FON 4 1 2.2uF Vo=1.6 X VSET 3 VO VIN VSET GND FON 5,6,7,8 C2 2.2uF FAN APE8872 PACKAGE ORDERING INFORMATION APE8872X 8872M Y WW SSS Package Type M : SOP-8L Data and specifications subject to change without notice Part number ID code: internal WW: 01~52 Year: 8 : 2008 1 200808284 Advanced Power Electronics Corp. APE8872 ABSOLUTE MAXIMUM RATINGS VIN Supply Voltage (VIN) ……………………………… -0.3 to 7 V FON Input Voltage (VFON) …………………………… -0.3V to VIN VSET Voltage (VSET) …………………………………… -0.3V to VIN Power Dissipation (PD) ……………………………… Internally limited Storage Temperature Range (T ST) ………………… -65 to +150°C Junction Temperature Range (T J) ………………… -40 to 125°C Operating Temperature Range (T OP) ……………… -40 to +85°C Thermal Resistance from Junction to case (R thjc) 20°C/W Thermal Resistance from Junction to ambient (Rthja) 60°C/W Note: Rthja is measured with the PCB copper area approximately 1.5 in 2 (Multi-layer) PACKAGE INFORMATION FON 1 VIN 2 VO 3 VSET 4 ( Top View ) 8 GND APE8872 7 GND 6 GND 5 GND SOP-8L ELECTRICAL SPECIFICATIONS (VSET = 2V, VIN = 5V, Io = 0.5A, CIN=COUT=2.2uF, TA=25°C unless otherwise specified) Parameter SYM VIN Supply Voltage Range VIN Quiescent Current ICCQ Output Voltage/VSET Voltage VO/VSET TEST CONDITION VO=5V, No Load VIN=5.5V, VSET=1V~3.2V MIN UNITS TYP MAX 4.5 - 5.5 V - 1 - mA 1.552 1.6 1.648 V/V Line Regulation VIN=4.5V to 5.5V - 0.2 0.5 % Load Regulation IO=10mA ~ 0.5A - 0.2 0.5 % IO =0.5A, VSET=3.4V - 300 400 mΩ - 1.5 3 A Vo<0.6V - 0.5 3 A - 1 - V nA Output Resistance RDS(ON) Current Limit ILimt Short Circuit Current IShort Minimum VSET Voltage VSET VSET Pin Current FON Pin Logic Threshold Voltage - 80 200 VFON-H ISET Normal Operating 2 - - VFON-L Regulator Fully On - - 0.8 FON Pin Bias Current IFON Thermal shutdown Temp TSD Thermal Shutdown Hysteresis FON=0V V - 1.5 10 uA - 150 - °C - 40 - °C 2 Advanced Power Electronics Corp. APE8872 PIN DESCRIPTIONS PIN SYMBOL PIN DESCRIPTION GND GND pin VIN IC power supply pin VO Output Pin. Its voltage is 1.6 times of VSET This pin sets the output voltage. Its voltage must be larger than 1V to guarantee VSET VO 1.6 times of VSET FON Input. Pulling this pin below 0.4V turns the regulator fully on. Internally pulled high. FON BLOCK DIAGRAM VO VIN Current Limit and Short Protection - + Error Amp Thermal Shutdown FON VO Fully On Logic GND VSET FUNCTION DESCRIPTION Output Voltage Regulation The Output Voltage is set by VSET voltage. VO output voltage follows the 1.6 times of VSET voltage until it reaches VIN voltage. Current-Limit The APE8872 monitors the current via the output PMOS and limits the maximum current to prevent load and APE8872 from damages during overload or short circuit conditions. Short Current Protection When the output voltage drops below 0.6V (typical), which is caused by over load or short circuit, the fold back current limit circuitry limits the output current to 500mA. The fold back current limit is used to reduce the power dissipation during short circuit condition. Thermal Shutdown A thermal shutdown circuit limits the junction temperature of APE8872. When the junction temperature exceeds +150°C, a thermal sensor turns off the output PMOS, allowing the device to cool down. The regulator regulates the output again through initiation of a new soft-start cycle after the junction temperature cools by 40°C, resulting in a pulsed output during continuous thermal overload conditions. 3 Advanced Power Electronics Corp. APE8872 APPLICATION INFORMATION Capacitor Selection Normally, use a 2.2uF capacitor on the input and a 2.2uF capacitor on the output of the APE8872. In order to insure the circuit stability, the proper output capacitor value should be larger than 1uF. With X5R and X7R dielectrics, 2.2uF is sufficient at all operating temperatures. Thermal Considerations The APE8872 series can deliver a current of up to 500mA over the full operating junction temperature range. However, the maximum output current must be dated at higher ambient temperature to ensure the junction temperature does not exceed 125°C. With all possible conditions, the junction temperature must be within the range specified under operating conditions. Power dissipation can be calculated based on the output current and the voltage drop across regulator. PD = (VIN - VO) IO The final operating junction temperature for any set of conditions can be estimated by the following thermal equation: PD (MAX) = (TJ (MAX) - TA) / Rthja Where TJ (MAX) is the maximum junction temperature of the die (125° C) and TA is the maximum ambient temperature. The junction to ambient thermal resistance (Rthja) for SOP-8L package at recommended minimum footprint is 60°C/W. Visit our website in which “Recommended Footprints for Soldering Surface Mount Packages” for detail. PCB Layout 1. Please place the input capacitors close to the VIN 2. Ceramic capacitors for load must be placed near the load as close as possible 3. To place APE8872 and output capacitors near the load is good for performance. 4. Large current paths that VIN and Output lines must have wide tracks. 5. GND connect large copper area can reduced IC temperature. 4 ADVANCED POWER ELECTRONICS CORP. Package Outline : SO-8 D Millimeters 8 7 6 5 E1 1 2 3 4 e B E SYMBOLS MIN NOM MAX A 1.35 1.55 1.75 A1 0.10 0.18 0.25 B 0.33 0.41 0.51 c 0.19 0.22 0.25 D 4.80 4.90 5.00 E 5.80 6.15 6.50 E1 3.80 3.90 4.00 e 1.27 TYP G 0.254 TYP L 0.38 － 0.90 α 0.00 4.00 8.00 A A1 G 1.All Dimension Are In Millimeters. 2.Dimension Does Not Include Mold Protrusions. Part Marking Information & Packing : SO-8 Part Number 8872M YWWSSS Package Code Date Code (YWWSSS) Y：Last Digit Of The Year WW：Week SSS：Sequence 5