Bay Linear Inspire the Linear Power B2526 Dual USB High Side Power Switch Description Features • • • • • • • • • The Bay Linear B2526 is a dual high-side power switch recommended for self-powered and bus-powdered universal serial for bus (USB) application conforming to USB requirements. USB voltage drop requirements, fault current limited to 750mA, flag output to indicate fault connections to the local USB controller are features that meet USB requirements. Additional features such as thermal shutdown to prevent catastrophic switch failure from excessively high current loads, under voltage lockout (UVLO) to ensure that the device remains off unless there is a valid input voltage present, and 3.3V or 5V logic compatible enable inputs. Two versions of the enable pin, Active High or Active Low are available in 8pin Dip and 8-pin SOIC packages. Package Information 3.0V to 5.5V Input 110µ µA Typical on-State Supply Current 1µ µA Typical off-State Supply Current 500mA Minimum Continuous Load Current 1.25A Maximum Current Limit 2.4V Typical Under Voltage Lockout (UVLO) Open-Drain Fault Flag Pin Thermal Shutdown Available with Active-High or Active-Low Enable Applications • • • • • USB Host and self-Powered Hubs USB Power Management Battery-Charger Circuits Hot Plug-In Power Supplies Bus-Powered Hubs Ordering Information Package Active High B2526-1M B2526-1P SO-8 8 DIP EN (A) FLG (A) SO-8 EN (A) 1 8 FLAG (A) 2 FLAG (B) 3 BAY 7 B2526 6 EN (B) 4 5 1 2 Logic Charge Pump 3 4 Logic Charge Pump VOUT (A) VIN GND FLB (B) EN (B) Active Low B2526-2M B2526-2P 8 Out (A) 7 IN 5 Out (B) VOUT (B) Top View Bay Linear, Inc Enable 2418Armstrong St., Livermore CA USA 94550 6 GND Tel: (925) 606-5950, Fax: (925) 940-9556 www.baylinear.com B2526 ABSOLUTE MAXIMUM RATINGS OPERATING RATING Supply Voltage…………………………………...6V Fault Flag Voltage………………………………..6V Fault Flag Current……………………………..50mA Output Voltage……………………………………6V Output Current……………………Internally Limited Enable Input……………………………-0.3V to 12V Storage Temperature………………-65°C to +150°C Lead Temperature (Soldering 5 sec.)………….260°C Supply Voltage ..................................................+3V to +5.5V Ambient Operating Temperature.................... -40°C to +85°C Thermal Resistance SOIC .................................................................. 120°C/W DIP..................................................................... 130°C/W ELECTRICAL CHARACTERISTICS at VIN = 5V, Ta=25°C, unless otherwise specified. (Note 1) Units Parameters Conditions Typ Supply Current (Note1) Switch Off, OUT = Open (Note1) Switch On, OUT = Open Low to High Transition High to Low Transition, (Note1) VEN = 0V to 5.5V 0.75 110 2.1 1.9 ± 0.01 1 100 140 0.5 1 1 1 Min Enable Input Threshold Enable Input Current Enable Input Capacitance Switch Resistance Output Turn-On Delay Output Turn-On Rise Time Output Turn-Off Delay Output Turn-Off Fall Time Output Leakage Current Continuous Load Current Short Circuit Current Limit Current Limit Threshold Over temperature Shutdown Threshold Error Flag Output Resistance Error Flag Off Current UVLO Threshold VIN = 5V IOUT = 500mA, Each Switch VIN = 3.3V IOUT = 500mA, Each Switch RL = 10Ω RL = 10Ω RL = 10Ω RL = 10Ω Each output (output disabled) Each output Each output (enable into load), VOUT = 4.0V Ramped Load applied to enable output, VOUT ≤ 4.0V TJ Increasing TJ Decreasing VIN = 5.0V, IL = 10mA VIN = 3.3V, IL = 10mA VFLAG = 5V VIN = Increasing VIN = Decreasing 0.8 -1 Max 5 160 µA 2.4 V 1 µA pF 140 180 mΩ 20 20 10 0.5 0.5 0.75 1.6 135 125 10 15 0.01 2.5 2.3 1.25 2.2 ms ms µs µs µA A A A °C Ω 1 µA V General Note: Devices are ESD protected, however, handling precautions recommended. Note 1: Off is ≤ 0.8V and is ≥ 2.4V for the B2526-1. Off is ≥ 2.4V and on is ≤ 0.8V for the B2526-2. The Enable input has approximately 200mV of hysteresis. TEST CIRCUIT (Only 1 Output Shown) 5V 0.1µ µF Ferrite Bead 10K B2526 EN (A) FLG (A) FLG (B) EN (B) Out (A) IN IOUT RL CL + GND ILOAD (for Current Limit Response) Out (B) Functional Characteristics Test Circuit Bay Linear, Inc 2418Armstrong St., Livermore CA USA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556 www.baylinear.com B2526 PIN DESCRIPTION Pin No. Pin Name 1&4 EN (A)/(B) 2&3 FLAG (A)/(B) 6 GND 7 VIN 8&5 VOUT (A)/(B) Pin Function Enable (Input): Logic-compatible enables input. High input > 2.1V typical. Low input < 1.9V typical (B2526-1 active high, B2526 -2 active low). Fault Flag (Output): Active-low, open-drain output. Indicates over current, UVLO and thermal shutdown. Ground: Supply return. Supply Input: Output MOSFET drain. Also supplies IC’s internal circuitry. Connect to positive supply. Switch Output: Output MOSFET source. Typically connect to switched side of load. DETAILED DESCRIPITION Power Switch The power switch is an N-Channel MOSFET with a maximum on-state resistance of 140mΩ (VIN = 5V). the power switch supplies a minimum of 500mA per switch. Enable The Logic enable disables the power switch and the bias for the charge pump, driver and other circuitry to reduce the supply current to less than 5µA when a logic high is present on the EN pin for B2526-2 or a logic low is present on EN for B2526-1. The enable input is compatible with both TTL and CMOS logic levels. Driver The driver controls the gate voltage of the power switch. To Limit large current surges the driver incorporates circuitry that controls the rise and fall times of the output voltage. Charge Pump An internal charge pump supplies power to the driver circuit and provides the necessary voltages to pull the gate of the MOSFET above the source. Fault Flag FLG (A)/(B) FLG is a N-Channel, open drain MOSFET output. The fault flag is active (low) for one or more of the following conditions: undervoltage (while 2V < VIN < 2.7V), current limit or thermal shutdown. The flag output MOSFET is capable of sinking a 10mA load to typically 100mV above ground. Multiple FLG pins may be “wired NORed” to a common pull-up resistor. Thermal Shutdown An internal thermal sense circuit shuts off the power switch when the junction temperature rises to approximately 150°C. Hysteresis is built into the thermal sense circuit. Current Sense A sense FET monitors the current supplied to the load. When an overload or short circuit is encountered, the current sense circuitry sends a control signal to the driver. The driver in turn reduces the gate voltage and sends the power FET into its saturation region, which switches the output into a constant current mode. The 2526 current-limit profile exhibits a small foldback effect of approximately 500mA. Once this current-limit threshold is exceeded the device enters constant current mode. The constant current is specified as the short circuit current limit in the “Electrical Characteristics" table. It is important to note that the 2526 will deliver load current up to the current-limit Threshold which is typically 1.6A (2.2Amax)." Under-Voltage Lockout (UVLO) UVLO prevents the output MOSFET form turning on until VIN exceeds 2.5V. In the under-voltage state, the FLG will be low. After the switch turns on, if the voltage drops below approximately 2.3V, UVLO shuts off the output MOSFET and signals fault flag. Under-voltage detection functions only when at least one switch is enabled. Bay Linear, Inc 2418Armstrong St., Livermore CA USA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556 www.baylinear.com B2526 Bay Linear, Inc 2418Armstrong St., Livermore CA USA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556 www.baylinear.com B2526 B4300 B2526 Two-Port Self Powered Hub (Using B2526 & B4300) Bay Linear, Inc 2418Armstrong St., Livermore CA USA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556 www.baylinear.com B2526 BLOCK DIAGRAM TYPICAL APPLICATION VCC 5V 10K 100K 10K 100K 3.3V USB Controller B2526-2 VIN µF 0.1µ ON/OFF EN (A) VBUS D+ FLG (A) IN Over-Current FLG (B) GND D- + Out (A) Over-Current ON/OFF Ferrite Beads 47µF 47µ USB Port 1 GND µF 0.1µ EN (B) VBUS Out (B) D+ D- + USB Port 2 GND 47µF 47µ Data (Two Pair to USB Controller) 2 Port USB Self-Powered Hub Bay Linear, Inc 2418Armstrong St., Livermore CA USA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556 www.baylinear.com Advance Information- These data sheets contain descriptions of products that are in development. The specifications are based on the engineering calculations, computer simulations and/ or initial prototype evaluation. Preliminary Information- These data sheets contain minimum and maximum specifications that are based on the initial device characterizations. These limits are subject to change upon the completion of the full characterization over the specified temperature and supply voltage ranges. The application circuit examples are only to explain the representative applications of the devices and are not intended to guarantee any circuit design or permit any industrial property right to other rights to execute. Bay Linear takes no responsibility for any problems related to any industrial property right resulting from the use of the contents shown in the data book. Typical parameters can and do vary in different applications. Customer’s technical experts must validate all operating parameters including “ Typical” for each customer application. LIFE SUPPORT AND NUCLEAR POLICY Bay Linear products are not authorized for and should not be used within life support systems which are intended for surgical implants into the body to support or sustain life, in aircraft, space equipment, submarine, or nuclear facility applications without the specific written consent of Bay Linear President. Bay Linear, Inc 2418Armstrong St., Livermore CA USA 94550 Tel: (925) 606-5950, Fax: (925) 940-9556 www.baylinear.com