USB High-Side Power Switch

Transcription

1 SP2525A USB High-Side Power Switch FEATURES +3.0V to +5.5V Input Voltage Range 500mA Continuous Load Current per Channel 2.6V Undervoltage Lockout.25A Short Circuit Current Limit 00mΩ Maximum On-Resistance 75µA On-State Supply Current µa Shutdown Current Output can be Forced Higher than Input (Off-State) Thermal Shutdown Slow Turn On and Fast Turn Off Now Available in Lead Free Packaging Active-High Version: SP2525A- Active-Low Version: SP2525A-2 APPLICATIONS USB Power Management Hot Plug-In Power Supplies Battery Charger Circuit DESCRIPTION The SP2525A device is an integrated high-side power switch ideal for self-powered and buspowered Universal Serial Bus (USB) applications. The high-side switches are MOSFETs with 70mΩ RDS(ON), which meets USB voltage drop requirements for maximum transmission wire length. Multi-purpose open-drain fault flag output indicates over-current limiting, thermal shutdown, or undervoltage lockout. Output current is typically limited to 0.85A below the 5A safety requirement, and the thermal shutdown function shuts the switch off to prevent damage under overcurrent conditions. Guaranteed minimum output rise time limits inrush current during hot plug-in, minimizing EMI and preventing the voltage at the upstream port from dropping excessively. TYPICAL APPLICATION CIRCUIT EN FLG 2 3 SP2525A 8 Pin NSOIC NC 4 5 VCC 5.0V 33µF 4.50V TO 5.25V UPSTREAM VBUS 00mA MAX 0K USB CONTROLLER VBUS D+ D- + µf Cin DATA SPX52 ON/OFF EN V SP2525A OVERCURRENT FLG + 0µF Cout NC + Ferrite Bead 33µF Ferrite Bead 0.0 µf VBUS D+ D- 33µF, 6V Tantalum, or 00µF, 0V Electrolytic Bold line indicate high-current traces 0.0 µf DATA One Port Self Powered Hub

2 ABSOLUTE MAXIMUM RATGS These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. Supply Voltage(V )...7.0V Fault Flag Voltage ( )...7.0V Fault Flag Current (I FLG )...50mA Enable Input (V EN ) V to 5V Operating Temperature Range C to +85 C Storage Temperature Range C to +50 C Power Dissipation Per Package 8-pin NSOIC (derate 6.4mW/ O C above +70 O C)...500mW Unless otherwise noted, the following specifications apply for V = +5.0V, T A = 25 C. ELECTRICAL CHARACTERISTICS PARAMETER M. TYP. MAX. UNITS CONDITIONS Supply Current µa V EN = Logic "0" = Open V EN = Logic "" = Open Enable Input Voltage V V EN = Logic "0" V EN = Logic "" Enable Input Current µa V EN = Logic "0" V EN = Logic "" Enable Input Capacitance pf Output Mosfet Resistance mω Output Turn-On Delay 00 µs RL=0Ω each output Output Turn-On Rise Time µs RL=0Ω each output Output Turn-Off Delay µs RL=0Ω each output Output Turn-Off Fall Time µs RL=0Ω each output Output Leakage Current 0 µa Current Limit Threshold A Over-Temperature Shutdown 35 OC Threshold 25 T J increasing T J decreasing Error Flag Output Resistance Ω V = 5V,IL = 0mA V = 3.3V,I L = 0mA Error Flag Off Current 0.0 µa V FLAG = 5V UVLO Threshold V V increasing V decreasing 2

3 P DESCRIPTION Pin Number Pin Name Description E N Enable Input Active High for SP2525A- and Active Low for SP2525A-2. 2 FLG An active-low and open-drained fault flag output for power switch. It can indicate current limit if CTL is active. In normal mode operation, it also can indicate thermal shutdown or undervoltage. 3 G ND Chip power ground. 4 N C Not internally connected. 5, 7 I N Power supply input. 6, 8 O UT MOSFET switch output. 0K V CC +5V TEST CIRCUIT OFF ON SP2525A EN FLG 0Ω NC 0.µF BLOCK DIAGRAM FLG EN Charge Pump Driver Current Limit CS Power N-MOSFET Thermal Shutdown UVLO 3

4 APPLICATION FORMATION Error Flag The Error Flag is an open-drained output of an N-channel MOSFET, the FLG output is pulled low to signal the following fault conditions: input undervoltage, output current limit, and thermal shutdown. Current Limit The current limit threshold is preset internally. It protects the output MOSFET switches from damage resulting from undesirable short circuit conditions or excess inrush current, which is often encountered during hot plug-in. The low limit of the current limit threshold of the SP2525A allows a minimum current of 0.5A through the MOSFET switches. A current limit condition will signal the Error Flag. Thermal Shutdown When the temperature of the SP2525A exceeds 35ºC for any reasons, the thermal shutdown function turns off the MOSFET switch and signals the Error Flag. A hysteresis of 0ºC prevents the MOSFETs from turning back on until the chip temperature drops below 25ºC. Supply Filtering A 0.µF to µf bypass capacitor from to, located near the device, is strongly recommended to control supply transients. Without a bypass capacitor, an output short may cause ringing on the input (from supply lead inductance) which can damage internal control circuitry. Transient Requirements USB supports dynamic attachment (hot plugin) of peripherals. A current surge is caused by the input capacitance of a downstream device. Ferrite beads are recommended in series with all power and ground connector pins. Ferrite beads reduce EMI and limit the inrush current during hot-attachment by filtering high-frequency signals. Short Circuit Transient Bulk capacitance provides the short-term transient current needed during a hot-attachment event. A 33 µf/6v tantalum or a 00µF/ 0V electrolytic capacitor mounted close to the downstream connector at each port should provide sufficient transient drop protection. Printed Circuit Layout The Power circuitry of USB printed circuit boards requires a customized layout to maximize thermal dissipation and to minimize voltage drop and EMI. Input and Output The independent solid state switch connects the pin to the pin when enabled by a logic signal at EN. The pin is the power supply connection to the internal circuitry and the drain of the output MOSFET. The pin is the source for the MOSFET. Typically, the current in USB application will flow through the switch from to towards the load. If V is greater than V when a switch is enabled, the current will flow from to the pin because the MOSFET channels are bidirectional when switched on. The output source is allowed to be externally forced to a higher voltage than its input without causing unwanted current flow when the output is disabled. 4

5 V = +5.0V, T AMB = +25 O C unless otherwise noted. TYPICAL PERFORMANCE CHARACTERISTICS 70 Output On-Resistance vs. Supply Voltage 90 On-Resistance vs. Temperature Switch-ON Resistance (mω) ON Resistance (mω) Temperature ( C) Output On-Resistance vs. Supply Voltage 2.8 UVLO Threshold Voltage vs. Temperature Output On-Resistance vs. Temperature 00 ON-State Supply Current vs. Supply Voltage UVLO Threshold Voltage (V) Falling Rising Switch-ON Supply Current (µa) Temperature (ºC) UVLO Threshold Voltage vs. Temperature On-state Supply Current vs. Supply Voltage 00 ON-State Supply Current vs. Supply Voltage 0.0 OFF State Supply Current vs. Supply Voltage Switch-ON Supply Current (µa) Supply Current (µa) On-state Supply Current vs. Temperature Off-state Supply Current vs. Supply Voltage 5

6 V = +5.0V, T AMB = +25 O C unless otherwise noted. TYPICAL PERFORMANCE CHARACTERISTICS CTL Threshold Voltage vs. Supply Voltage Current Limit Threshold vs. Temperature Threshold Voltage (V) CTL Rising CTL Falling Output Threshold (A) Control Threshold vs. Supply Voltage Temperature ( C) Current Limit Threshold vs. Temperature Output Rise Time vs. Temperature Output Fall Time vs. Temperature Turn-ON Resistance (ms) Turn-off Fall Time (µs) Temperature ( C) Output Rise Time vs. Temperature Temperature ( C) Output Fall Time vs. Temperature V V EN V EN= R L=35Ω C L=5uF R L=35Ω C L=5uF 200mA/div 00mA/div Input Voltage Response 6 Turn-On, Turn-Off Characteristics

7 V = +5.0V, T AMB = +25 O C unless otherwise noted. TYPICAL PERFORMANCE CHARACTERISTICS V EN V EN R L =35Ω C L =33uF R L=35Ω C L=50uF 00mA/div 00mA/div Turn-On, Turn-Off Characteristics Turn-On, Turn-Off Characteristics V EN 5A/div A/div Short Circuit Response (Short Applied to Output) Short Circuit Response (Enable to Short Circuit) 5A/div A/div Short Circuit Transient Response (Short Applied to Output) 7 Current Limit Response (Ramped Load)

8 PACKAGE: 8 Pin NSOIC D/2 D SIDE VIEW E E/ E/2 E A A A2 Seating Plane Pin Designator to be within this DEX AREA (D/2 x E/2) e TOP VIEW 2 3 b 4 (L) FRONT VIEW Gauge Plane h h ø ø2 R R ø L2 L Seating Plane ø c SYMBOL 8 Pin NSOIC JEDEC MS-02 Variation AA Dimensions in Millimeters: Controlling Dimension M NOM MAX M NOM MAX A A A b c E E e h BSC 3.90 BSC.27 BSC BSC 0.54 BSC BSC L L L2 R REF 0.25 BSC REF 0.00 BSC - - R ø 0º - 8º 0º - 8º ø 5º - 5º 5º - 5º ø2 0º - - 0º - - D 4.90 BSC 0.93 BSC SIPEX Pkg Signoff Date/Rev: Dimensions in Inches Conversion Factor: Inch = mm JL Aug6-05 / Rev A 8

9 ORDERG FORMATION Part Number Temperature Range Package Types SP2525A-EN C to +85 C... 8-pin NSOIC SP2525A-EN/TR C to +85 C... 8-pin NSOIC SP2525A-2EN C to +85 C... 8-pin NSOIC SP2525A-2EN/TR C to +85 C... 8-pin NSOIC Available in lead free packaging. To order add -L suffix to part number. Example: SP2525A-EN/TR = standard; SP2525A-EN-L/TR = lead free /TR = Tape and Reel Pack quantity is 2,500 for 8 pin NSOIC. Solved by SipexTM Sipex Corporation Headquarters and Sales Office 233 South Hillview Drive Milpitas, CA TEL: (408) FAX: (408) Sipex Corporation reserves the right to make changes to any products described herein. Sipex does not assume any liability arising out of the application or use of any product or circuit described herein; neither does it convey any license under its patent rights nor the rights of others. 9