UNISONIC TECHNOLOGIES CO., LTD US3X77 CMOS IC POWER DISTRIBUTION SWITCH DESCRIPTION The UTC US3X77 is a power distribution switch and particularly designed for self-powered and bus-powered Universal Serial Bus (USB) applications. The UTC US3X77 incorporates protection circuits including current limiting circuit with foldback function, thermal shutdown circuit designed to prevent catastrophic switch failure due to increasing power dissipation when continuous heavy loads or short circuit occurs. Besides, a built-in charge pump is used to drive the N-channel MOSFET that is free of parasitic body diode to eliminate any reversed current flow across the switch when it is powered off. The RDS(ON) of the MOSFET switch is as low as 100mΩ. OC is open-drain output report over-current or over-temperature event which has deglitch typical 9ms timeout period typically 9ms. The UTC US3X77 is applied in high-side power protection switch, USB power management, USB host and self-powered bubs, USB bus-powered hubs, hot plug-in power supplies, battery-charger circuits. FEATURES * 100mΩ High-Side MOSFET * Supply Current: Switch on : 65μA(Typ) Switch off : 1μA (Max) * Accurate Current Limit with Foldback * Deglitched Open-Drain Over-Current Flag Output (OC) * No Reverse Current when Power Off * Under voltage Lockout * Operating Range:2.7V ~ 5.5V * Output Shutdown Pull-low Resistor ORDERING INFORMATION Ordering Number Lead Free Halogen Free US3X77XL-S08-R US3X77XG-S08-R US3X77XL-S08-T US3X77XG-S08-T Package Packing SOP-8 SOP-8 Tape Reel Tube US3X77XL-SM1-R US3X77XG-SM1-R MSOP-8 Tape Reel US3X77XL-SM1-T US3X77XG-SM1-T MSOP-8 Tube www.unisonic.com.tw Copyright © 2011 Unisonic Technologies Co., Ltd 1 of 10 QW-R502-568.B US3X77 CMOS IC PIN CONFIGURATION 1 8 OUT IN 2 7 OUT IN 3 6 NC EN(EN) 4 5 OC GND PIN DESCRIPTION PIN NO. 1 PIN NAME GND 2, 3 IN 4 5 6 EN(EN) OC NC 7, 8 OUT DESCRIPTION Ground Input Supply: Output MOSFET Drain, which also supplies IC's internal circuitry. Connect to positive supply. Enable: Logic level enable input. Make sure EN pin never floating. Over-Current: Open-Drain OC output. No connection. Switch Output: Output MOSFET Source of switch. Typically connect to switched side of load. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 2 of 10 QW-R502-568.B US3X77 CMOS IC BLOCK DIAGRAM UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 3 of 10 QW-R502-568.B US3X77 CMOS IC ABSOLUTE MAXIMUM RATING (TA = 25°C, unless otherwise specified) PARAMETER SYMBOL RATINGS UNIT Supply Voltage VIN 6 V Output Voltage VOUT 6 V Enable Input VEN -0.3 ~ 6 V Output Current IOUT Internally Limited A Storage Temperature TSTG -65~ +150 ℃ Reflow Temperature (Soldering, 10sec) 260 ℃ ESD Protection 2 kV Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged. Absolute maximum ratings are stress ratings only and functional device operation is not implied. OPERATING RATINGS PARAMETER Supply Voltage Operating Temperature SYMBOL VIN TA RATINGS +3 ~ +5.5 -40 ~ +85 UNIT V °C ELECTRICAL CHARACTERISTICS (VIN = 5V, CIN=1µF, COUT=1µF, RL=10Ω, TA = 25°C, unless otherwise specified) PARAMETER SYMBOL TEST CONDITIONS Input Voltage VIN US3477, IOUT=1.5A US3377, IOUT=1.0A Output MOS RDS(ON) US3277, IOUT=0.5A US3177, IOUT=0.3A Supply Current IIN Output Turn-on Rising Time RL=10Ω, 90% Settling US3477 US3377 Current Limit Threshold ITHD(LIMIT) VOUT=4V US3277 US3177 US3477 VOUT=0V, US3377 Short-Circuit Current ISC 2.7V<VIN<5.5V US3277 US3177 EN Input Threshold Shutdown Supply Current Shutdown Pull Low Resistance Output Leakage Current VIN Under Voltage Lockout VIN Under Voltage Hysteresis Thermal Limit Thermal Limit Hysteresis OC Deglitch OC Output Low Voltage OC Off-State Current MIN 2.7 2 1.6 1.2 0.75 0.2 0.2 0.2 0.2 1 ISHDN IO(LEAK) EN=”0”, VOUT=0V 2.2 OC assertion or deassertion IOC= 5mA VOC = 5V UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 4 TYP MAX UNIT 5.5 V 100 115 65 400 2.5 2 1.5 1 1.7 1.3 1 0.7 1.6 0.1 75 0.5 2.5 200 135 20 9 mΩ µA µs 3.3 2.6 1.9 1.45 2.3 1.7 1.3 0.9 1.8 1 150 1 2.7 15 0.4 1 A A V µA Ω µA V mV ℃ ℃ ms V µA 4 of 10 QW-R502-568.B US3X77 CMOS IC FUNCTIONAL DESCRIPTION OVERCURRENT PROTECTION When the output load exceeds the current-limit threshold, The Over Current Protection will be triggered. The typical current limit value of UTC US3077/US3277/US3377/US3477 is 1A, 1.5A, 2A, 2.5A. There is foldback of current limit when short-circuit being encountered. OC RESPONSE The OC open-drain output is asserted (active low) when an over current or over-temperature shutdown condition is encountered after a 9-ms deglitch timeout. The output remains asserted until the over-current or over-temperature condition is removed. THERMAL SHUTDOWN Thermal shutdown protects UTC US3X77 from excessive power dissipation. If the die temperature exceeds 135°C, the MOSFET switch is shut off. 20°C of hysteresis prevents the switch from turning on until the die temperature drops to 115°C. Thermal shutdown circuit functions only when the switch is enabled. UNDERVOLTAGE LOCKOUT (UVLO) UVLO (under-voltage lockout) prevents the output MOSFET from turning on until IN (input voltage) exceeds 2.5V typically. After the switch turns on, if the voltage drops below 2.3V typically, UVLO shuts off the output MOSFET. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 5 of 10 QW-R502-568.B US3X77 CMOS IC TEST CIRCUITS RFG VIN IN OC UTC US3X77 CI Chip Enable OUT EN GND VFLG S1 A IOUT VOUT CO RL IL Turn-On & Off Response, Flag Response UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 6 of 10 QW-R502-568.B US3X77 CMOS IC TYPICAL APPLICATION CIRCUIT Pull-Up Resistor (10K ~ 100K) RFG Supply Voltage 5V 10K IN OC USB Controller Over Current 0.1µF UTC US3X77 1µF Chip Enable Flag Transient Filtering EN VBUS D+ DGND OUT GND 0.1µF 150µF Ferrite Beades Data Note. A low-ESR 150μF aluminum electrolytic or tantalum between VOUT and GND is strongly recommended to meet the 330mV maximum droop requirement in the hub VBUS. POWER SUPPLY CONSIDERATIONS A 1μF bypass capacitor on IN pins, a high value capacitor and a 0.1uF bypass capacitor on OUT pins， are strongly recommended， because this precaution can reduce a poor risk that an output short may cause sufficient ringing on the input to damage internal control circuitry. Input transients must not exceed the absolute maximum supply voltage (6V) even for a short duration. ENABLE INPUT EN must be driven logic high or logic low for a clearly defined input. Floating the input may cause unpredictable operation. EN should not be allowed to go negative with respect to GND. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 7 of 10 QW-R502-568.B US3X77 CMOS IC TYPICAL CHARACTERISTICS (TA=25°C, VIN= 5V, 3275H, CIN=1μF, COUT=1μF, VEN=0V, unless otherwise specified.) Turn on delay time and rise time Turn off delay time and fall time 8V 8V VIN=5V CL=120μF 6V 6V RL=5Ω 4V 4V 2V 2V 0 0 10V 10V 5V 5V VIN=5V CL=120μF RL=5Ω 0 0 VOC 1A IOUT 0.5A 0 0 5V 5V 0 VIN=5V RL=5Ω 2000 5V VOC VOC 2000 4000 Thermal Shutdown Response 10V VIN=5V CL=47μF RL=1Ω CL=220μF VOUT 1A 0.5A IOUT IOUT VIN=5V RL=5Ω Time (400μs/div) Inrush Current With Different Load Capacitance 0 5V 0 VEN VEN 0 0 4000 Time (400μs/div) 0 CL=120μF 1A 0.5A 0 10 Inrush Current With Different Load Capacitance 0 CL=10μF 5 Time (1ms/div) 5V VEN VOC 0 10V 5V 0 IOUT 4000 Inrush Current With Different Load Capacitance 10V VEN 2000 Time (400μs/div) 0 VIN=5V RL=5Ω 0 5 10 Time (1ms/div) UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 8 of 10 QW-R502-568.B US3X77 CMOS IC TYPICAL CHARACTERISTICS (Cont.) VOUT VIN VIN VOUT Short-circuit current, device enable into short Short circuit response at start up CL=47μF IOUT 2A 0 1A 10V 0 5V VOC IOUT 2A 5V 5V VEN 0 VIN 10V 0 0 500 VIN=5V CIN=47μF CL=47μF 0 0 1000 2000 4000 Time (400ms/div) IOUT IOUT VOUT VIN VOC VIN VOUT Time (100ms/div) UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 9 of 10 QW-R502-568.B US3X77 CMOS IC TYPICAL CHARACTERISTICS (Cont.) IOUT VIN VOC VOUT UTC assumes no responsibility for equipment failures that result from using products at values that exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or other parameters) listed in products specifications of any and all UTC products described or contained herein. UTC products are not designed for use in life support appliances, devices or systems where malfunction of these products can be reasonably expected to result in personal injury. Reproduction in whole or in part is prohibited without the prior written consent of the copyright owner. The information presented in this document does not form part of any quotation or contract, is believed to be accurate and reliable and may be changed without notice. UNISONIC TECHNOLOGIES CO., LTD www.unisonic.com.tw 10 of 10 QW-R502-568.B