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.
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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
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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
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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
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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(℃ )
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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
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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
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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.
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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
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