EUP3510

Preliminary EUP3510 Current Limited Load Switch DESCRIPTION The EUP3510 is a Current Limited P-channel MOSFET power switch designed for high-side load-switching applications. An integrated current-limiting circuit protects the input supply against large currents which may cause the supply to fall out of regulation. It can be used to control loads that require up to 1A. In order to fit different application, current limit threshold is programmed with a resistor from SET Pin to ground. The quiescent supply current is typically a low 8µA, making the device ideal for portable battery-operated equipment. In shutdown mode, the supply current decreases to less than 0.1µA. Additional features include thermal shutdown to prevent catastrophic switch failure from high current loads, under-voltage lockout (UVLO) to ensure that the device remains off unless there is a valid input voltage present. The EUP3510 is available in a 5 pin SOT-23 package. FEATURES 2.4V to 5.5V Input voltage range Programmable over current threshold Fast transient response: Low quiescent current - 8µA typical - 1µA max with shutdown 135m typical RDS(ON) Only 1.8V needed for ON/OFF Control Under-Voltage Lockout Thermal shutdown Temp range -40 to 85°C Available in SOT23-5 package RoHS Compliant and 100% Lead(Pb)-Free APPLICATIONS Peripheral ports Notebook computers Personal communication devices Hot swap supplies Typical Application Circuit Figure 1. DS3510 Ver0.1 Mar. 2008 1 Preliminary Block Diagram EUP3510 Figure 2. Pin Configurations Package Type Pin Configurations (Top View) SOT23-5 Pin Description PIN 1 2 3 4 5 NAME VOUT GND SET ENB VIN DESCRIPTION P-type MOSFET Drain, connect 0.47uF capacitor from VOUT to Ground Ground Current-Limit Set Input. A resistor RSET from SET to ground sets the current limit for the switch Enable Input, active-low P-channel MOSFET Source, connect 1uF capacitor from VIN to Ground DS3510 Ver0.1 Mar. 2008 2 Preliminary Ordering Information Order Number EUP3510VIR1 Package Type Marking EUP3510 Operating Temperature Range -40 °C to 85°C SOT23-5 40xxxx EUP3510 □ □□□ Lead Free Code 1: Lead Free 0: Lead Packing R: Tape & Reel Operating temperature range I: Industry Standard Package Type V:SOT23 DS3510 Ver0.1 Mar. 2008 3 Preliminary Absolute Maximum Ratings EUP3510 S upply Voltage (V IN t o GND) --------------------------------------------------- -0.3V to 6V Supply Voltage (ENB to GND) ---------------------------------------------------0.3V to VIN+0.3 Output Voltages (SET,VOUT to GND) --------------------------------------------- -0.3V to VIN+0.3 S torage Temperature ------------------------------------------------------- -65°C to 150°C R eflow Temperature (soldering,10sec) ----------------------------------------------- 2 60°C Thermal Resistance θJA (SOT23-5) ------------------------------------------------------ 220°C/W ESD Rating Human Body Model --------------------------------------------------------------------------------2kV Operating Ratings Supply Voltage (VIN) --------------------------------------------------------------- 2.4V to 5.5V O perating Temperature (T A ) ---------------------------------------------40°C to +85°C Electrical Characteristics Unless otherwise specified, VIN = 5V,CIN=1uF,COUT=0.47uF, TA=-40℃~+85℃. Symbol VIN RDS(ON) ILIM IQ IQ(OFF) VUVLO VUVLO-HYS VON(L) VON(H) ION(SINK) TOFF TON TSD TSD-HYS Parameter Operating Voltage VIN=5V On-Resistance Current Limit Quiescent Current Off Supply Current VIN Under Voltage Lockout VIN Under Voltage Hysteresis ON Input Low Voltage ON Input Hige Voltage ON Input leakage Turn_Off Time Turn_On Time Thermal Shutdown Temp. TSD Hysterisis Conditions EUP3510 Units Min. Typ. Max. 2.40 -135 140 160 750 1035 8.1 0.1 1.22 1.16 1.26 1.55 185 1.30 1.51 0.1 12 20 135 20 1.36 1.55 1 5.50 205 210 240 1225 11.5 1 1.91 V m m m mA uA uA V mV V V uA us us ℃ ℃ VIN=4.5V VIN=3V VOUT=0V,Rset=6.8K VIN=5V, VON=0V, IOUT=0A VIN=5V, VON=5V, IOUT=0A VIN Falling VIN Rising VIN=5V VON=5V VIN=5V, RL=10 VIN=5V, RL=10 DS3510 Ver0.1 Mar. 2008 4 Preliminary Typical Operating Characteristics (unless otherwise noted ,VIN=5V, TA=25°C.) Quiescent Current vs. Temperature 20 EUP3510 Quiescent Current vs. Input Voltage 20 Quiescent Current (uA) 15 Quiescent Current (mA) -40 -20 0 20 40 60 80 100 120 15 10 10 5 5 0 0 0.0 1.0 Temperature(° C) 2.0 3.0 4.0 Input Voltage (V) 5.0 6.0 Output Current vs VOUT 0.6 RDS(ON) vs. Temperature 240 220 200 180 160 140 120 100 80 60 40 20 0 -40 -20 0 Input=3V Output Current (A) RSET=16k Ron (m ) 0.4 Input=5V 0.2 0 0 1 2 3 Vout (V) 4 5 20 40 60 80 100 120 Temperature(℃ ) Off-Supply Current vs. Temperature 1.000 10.00 Off-Supply Current vs. Temperature Off_Supply Current (uA) 0.100 Off-Switch Current (uA) -40 -20 0 20 40 60 80 100 120 1.00 0.010 0.10 0.001 0.01 -40 -20 0 20 40 60 80 100 120 Temperature(℃ ) Temperature(℃ ) DS3510 Ver0.1 Mar. 2008 5 Preliminary Typical Operating Characteristics (unless otherwise noted ,VIN=5V, TA=25°C.) Turn-On vs. Temperature RLOAD=10 , CLOAD=0.47µF 30 VIN=3V Turn-Off Time (uS) Turn-On Time (uS) EUP3510 Turn-On vs. Temperature RLOAD=10 , CLOAD=0.47µF 30 25 20 15 10 5 VIN=5V VIN=3V 20 VIN=5V 10 0 -40 -20 0 20 40 60 80 100 120 Temperature(℃ ) 0 -40 -20 0 20 40 60 80 100 120 Temperature(℃ ) RSET Coefficient vs. ILMT 10 VIH and VIL vs. VIN 2.20 2.00 9 Rset Ilim Product (KV) 8 VIH and VIL (V) 1.80 1.60 1.40 1.20 1.00 0.80 V IH 7 6 V IL 5 0 0.5 1 ILM T (A) 1.5 2 2.5 3.0 3.5 4.0 VIN(V) 4.5 5.0 5.5 RSET vs. ILMT 100 Rset (K ) 10 1 0.1 1 ILMT (A) 10 DS3510 Ver0.1 Mar. 2008 6 Preliminary Typical Operating Characteristics (unless otherwise noted ,VIN=5V, TA=25°C.) Turn-Off RL=10 , CL=0.47µF EUP3510 Turn-On RL=10 , CL=0.47µF ENB ENB VOUT VOUT Short Circuit through 0.3 Output Short-Circuit Response Output Current Input Current Input Voltage Short to 1 Output Voltage Load Output Voltage DS3510 Ver0.1 Mar. 2008 7 Preliminary Detailed Description The EUP3510 limits load current by sampling the pass transistor current and passing that through an external resistor, RSET. The voltage across RSET, VSET, is then compared with an internal reference voltage, VREF. In the event that load current surpasses the set limit current, VSET will exceed VREF causing the pass transistor gate voltage to increase, thereby reducing the gate to source voltage of the PMOS switch and regulating its current back down to ILIMIT. When the device detect VOUT is less than 1V, the limit current will fold-back to about 60% of ILMT. Setting the Current Limit Level Setting the current limit level on the EUP3510 requires some care to ensure the maximum current required by the load will not trigger the current limit circuitry. The minimum current limit threshold should be determined by taking the maximum current required by the load, ILOAD, and adding 25 % headroom. The EUP3510 has a current limit tolerance of 25 %, which is largely a result of process variations from part to part, and also temperature and VIN/VOUT variances. Thus, to ensure that the actual current limit is never below the desired current limit a 1/0.75 = 1.33 coefficient needs to be added to the calculations. Knowing the maximum load current required, the value of RSET is calculated as follows. EUP3510 The maximum power dissipation in any application is dependant on the maximum junction temperature, TJ(MAX)=125°C, the junction-to-ambient thermal resistance for the SOT23-5 package, θJA=220 °C/W, and the ambient temperature, TA, which may be formulaically expressed as: P (max) = TJ (max) − TA θ JA = 125 − TA 220 It then follows that assuming an ambient temperature of 60°C, the maximum power dissipation will be limited to about 295 mW. Reverse Voltage The EUP3510 is designed to control current flowing from IN to OUT. If the voltage on OUT is raised higher than IN current will flow from OUT to IN but the current limit function will not be available, as can be inferred from the block diagram in Figure 2. Thus, in applications were OUT is used to charge IN, careful considerations must be taken to limit current through the device and protect it from becoming damaged. R SET = R SET cofficient / I LIMIT where ILIMIT = (ILOAD × 1.33) × 1.25 and RSET coefficient is 7500 for a 1A current limit. For typical RSET coefficient values given a limit current refer to the "Typical Characteristics" section. Operating at Current Limit and Thermal Shutdown In the event that a load higher than ILIMIT is demanded of the EUP3510, the load current will stay fixed at the current limit established by RSET. However, since the required current is not supplied, the voltage at OUT will drop. The increase in VIN -VOUT will cause the chip to dissipate more heat. The power dissipation for the EUP3510 can be expressed as P = I L OAD × (VIN − VOUT ) Once this exceeds the maximum power dissipation of the package, the die temperature will rise. When the die temperature exceeds an over-temperature limit of 135 °C, the EUP3510 will shut down until it has cooled down to 115°C, before starting up again. As can be seen in the figure below, the EUP3510 will continue to cycle on and off until the load is reduced or the part is turned off. DS3510 Ver0.1 Mar. 2008 8 Preliminary Packaging Information SOT23-5 EUP3510 SYMBOLS A A1 D E1 E L b e MILLIMETERS MIN. MAX. 1.30 0.00 0.15 2.90 1.60 2.60 3.00 0.30 0.60 0.30 0.50 0.95 INCHES MIN. 0.000 0.114 0.063 0.102 0.012 0.012 0.037 0.118 0.024 0.020 MAX. 0.052 0.006 DS3510 Ver0.1 Mar. 2008 9