ACE345 Adjustable USB Load Current Switch Description The ACE345 is Adjustable USB Load Current Switch Current Limited designed for high-side load switching applications. The internal current-limiting circuit protects the input supply against large output short circuit current which may cause the supply to fall out of regulation. The current limit threshold is programmed with an external resistor from ISET Pin to ground. The quiescent supply current is typically 150μA, 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 and constant current output characteristics if current exceed its current limit Features 2.5 to 5.5V input voltage range Controlled turn-on 0.15-1.5A adjustable current limit +/-6% current limit accuracy 0.1ohm on resistance Fast current limit response time Logic Control Shutdown (IQ<1uA) Thermal shutdown and UVLO Reverse current blocking Application Portable Devices MID, MP4… Set top boxes Notebook and PC mother board USB supplied Devices Absolute Maximum Ratings Parameter Max Unit Max Input Voltage 6 V Max Operating Junction Temperature(TJ) 125 ℃ Ambient Temperature(TA) -40~85 ℃ Maximum Power Dissipation 250 mW Storage Temperature(TS) ESD (HBM) -40~150 ℃ >4000 V Note: Exceed these limits to damage to the device. Exposure to absolute maximum rating conditions may affect device reliability. VER 1.2 1 ACE345 Adjustable USB Load Current Switch Packaging Type SOT-23-5 5 1 4 2 3 SOT-23-5 Description Function 1 VOUT Switch Output, the output of power switch 2 GND 3 ISET 4 ON Ground Current limit setting pin. Connecting a resistor (R_Iset) from this pin to ground will adjust the current limit Control input, enable pin, active high 5 VIN Supply input voltage Ordering information ACE345 XX + H Halogen - free Pb - free BN : SOT-23-5 Recommended Work Conditions Parameter Max Unit Input Voltage Range 5.5 V Operating Junction Temperature (TJ) -20~125 ℃ Typical Application ACE345 VER 1.2 2 ACE345 Adjustable USB Load Current Switch Electrical Characteristics (VIN=5V,TA=25℃.) Parameter Symbol Input Voltage Range Vin Quiescent Current Conditions Min Typ Max Units 2.6 Active, Vfb=0.65, No Switching Iq 5.5 150 Shutdown Switch Rdson Rdson Adjustable current limit Llimit Reverse Voltage Leakage Current Irevlk ON Input High Voltage Vh_on ON Input Low Voltage Vl_on Thermal shutdown Temp Tsd V 300 uA 1 Iout=500mA R_Iset=53K ohm R_Iset=25K ohm R_Iset=17K ohm 100 0.5 1.0 1.5 150 Vout=5V, Vin=0V 0.1 5 mΩ A 1.5 uA V 0.4 V ℃ 155 Setting The Current Limit Threshold RILIM (KΩ) Typical Current Limit (mA) RILIM (KΩ) Typical Current Limit (mA) 200 138 51 520 180 152 43 612 151 179 30 873 100 266 20 1295 82 324 15.1 1705 68 389 VER 1.2 3 ACE345 Adjustable USB Load Current Switch Electrical Performance Tested under TA=25℃, unless otherwise noted VER 1.2 4 ACE345 Adjustable USB Load Current Switch Electrical Performance Tested under TA=25℃, unless otherwise noted VER 1.2 5 ACE345 Adjustable USB Load Current Switch Block Diagram Detailed Description Operation The ACE345 is a current limited switch that protects systems and loads which can be damaged or disrupted by the application of high currents. The core of each device is a 0.10Ω P-channel MOSFET and a controller capable of functioning over a wide input operating range of 2.6-5.5V. The controller protects against system malfunctions through current limiting, undervoltage lockout and thermal shutdown. The current limit is adjustable from 0.15A to 1.5A through the selection of an external resistor. On/Off control The ON pin controls the state of the switch. When ON is high, the switch is in the on state. Activating ON continuously holds the switch in the on state so long as there is no fault. An undervoltage on VIN or a junction temperature in excess of 155°C overrides the ON control to turn off the switch. The ACE345 does not turn off in response to an over current condition but instead remains operating in a constant current mode so long as ON is active and the thermal shutdown or undervoltage lockout have not activated. The ON pin control voltage and VIN pin have independent and recommended operating ranges. The ON pin voltage can be driven by a voltage level higher than the input voltage. VER 1.2 6 ACE345 Adjustable USB Load Current Switch Current limiting The current limit ensures that the current through the switch doesn't exceed a maximum value while not limiting at less than a minimum value. The current at which the parts will limit is adjustable through the selection of an external resistor connected to ISET. Information for selecting the resistor is found in the Application Info section. The ACE345 has no current limit blanking period so it will remain in a constant current state until the ON pin is deactivated or the thermal shutdown turns-off the switch. Thermal Shutdown The thermal shutdown protects the die from internally or externally generated excessive temperatures. During an over-temperature condition the switch is turned-off. The switch automatically turns-on again if temperature of the die drops below the threshold temperature. Packing Information SOT-23-5 VER 1.2 7 ACE345 Adjustable USB Load Current Switch Notes ACE does not assume any responsibility for use as critical components in life support devices or systems without the express written approval of the president and general counsel of ACE Electronics Co., LTD. As sued 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 shoes 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 to the user. 2. A critical component is 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. ACE Technology Co., LTD. http://www.ace-ele.com/ VER 1.2 8