19-3463; Rev 1; 2/10 KIT ATION EVALU E L B AVAILA Triple 1.2A USB Switch in 4mm x 4mm Thin QFN The MAX1564 triple, current-limited USB switch comes in a space-saving, 16-pin, 4mm x 4mm thin QFN package. Each channel meets all IEC specifications for USB ports. The device is capable of supplying up to 1.2A from each output. The MAX1564 has multiple protection features, including thermal shutdown to limit junction temperature in case of a prolonged short or overload condition. Reverse-current protection circuitry blocks current flow from output to input regardless of the switch state. The IC has accurate, user-programmable current-limiting circuitry to protect the input supply against overload. Each output of the MAX1564 has short-circuit protection that latches off the switch when the output is shorted for more than 20ms, thereby saving system power. Auto-restart then tests the shorted output with a 25mA current to determine when the short is removed, then automatically restarts the output. Independent opendrain fault signals notify the microprocessor that the internal current limit has been reached. A 20ms faultblanking feature allows momentary faults to be ignored, such as those caused when hot-swapping into a capacitive load. This feature helps avoid issuing false alarms to the host system. Blanking also suppresses errant fault signals when the device is powering up. Applications Features o Tiny 16-Pin 4mm x 4mm Thin QFN Package o Reverse-Current Blocking o Programmable Current Limit o Auto-Restart when Fault Is Removed o 12% Accurate Current Limit o Up to 1.2A Load Current for Each Output o Thermal-Overload Protection o Built-In 20ms Fault Blanking o Compliant with All USB Specifications o 2.7V to 5.5V Input Supply Range o Independent Fault Indicator Outputs o Active-High/Active-Low Select Pin o ±15kV ESD Protection (with Caps) Ordering Information PART MAX1564ETE TEMP RANGE PIN-PACKAGE -40°C to +85°C 16 Thin QFN-EP* 4mm x 4mm *EP = Exposed pad. USB Ports USB Hubs Notebook Computers Pin Configuration Desktop Computers GND OUTB OUTC TOP VIEW OUTA Docking Stations 12 11 10 9 FLTA 13 8 FLTC ONC 14 7 FLTB ONB 15 6 SETI ONA 16 5 SEL 2 3 4 INB INC INA 1 VCC MAX1564 THIN QFN 4mm X 4mm ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.. 1 MAX1564 General Description MAX1564 Triple 1.2A USB Switch in 4mm x 4mm Thin QFN ABSOLUTE MAXIMUM RATINGS IN_, ON_, OUT_, SEL, VCC to GND (Note 1)............-0.3V to +6V FLT_, SETI to GND .....................................-0.3V to (VCC + 0.3V) IN_ to OUT_ (when disabled, Note 2) .........................-6V to +6V IN_ to OUT_ (when enabled, Note 3)....................-1.5A to +2.3A FLT_ Sink Current................................................................20mA Note 1: Note 2: Note 3: Continuous Power Dissipation 16-Pin 4mm x 4mm Thin QFN (derate 16.9mW/°C above +70°C) .............................1349mW Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-65°C to +150°C Lead Temperature (soldering, 10s) ................................+300°C INA, INB, INC, and VCC must be connected together externally. Reverse current (current from OUT_ to IN_) is blocked when disabled. Forward and reverse current are internally limited. Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VIN_= VCC = VSEL = VON_= 5V, RSETI = 26.1kΩ, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 4) PARAMETER CONDITIONS Supply Voltage Range MIN VIN_ = VCC = 5V, TA = +25°C Switch On-Resistance IOUT_ = 0A OUT_ Off-Leakage Current VON_ = 0V, VOUT_ = 0V Undervoltage-Lockout Threshold VIN_ rising, 3% hysteresis Short-Circuit Current Limit (RMS Amps) Short-Circuit/Continuous CurrentLimit Transition Output Voltage Threshold 2 mΩ 100 7.5 VONA = 5V, VONB = VONC = 0V 40 80 VONA = VON0B = 5V, VONC = 0V 55 100 2.2 Continuous Load Current Short-Circuit Current Limit (Peak Amps) V 3 VONA = VONB = VONC = 5V Current-Limit Threshold UNITS 5.50 80 30 VON_ = 0V IN Quiescent Supply Current MAX 60 VIN_ = VCC = 3V, TA = +25°C VIN_ = VCC = 5V, TA = -40°C to +85°C IN Standby Supply Current TYP 2.75 60 120 0.02 10 2.5 2.7 1.2 1.20 1.37 1.54 RSETI = 39.2kΩ 0.79 0.91 1.03 RSETI = 60.4kΩ 0.49 0.59 0.68 1.46 1.8 2.20 VOUT_ = 0V VOUT_ = 0V (Note 5) µA µA V A RSETI = 26.1kΩ RSETI = 26.1kΩ µA RSETI = 39.2kΩ 1.2 RSETI = 60.4kΩ 0.77 RSETI = 26.1kΩ 0.55 RSETI = 39.2kΩ 0.37 RSETI = 60.4kΩ 0.23 1 _______________________________________________________________________________________ A A A(RMS) V Triple 1.2A USB Switch in 4mm x 4mm Thin QFN (VIN_= VCC = VSEL = VON_= 5V, RSETI = 26.1kΩ, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) (Note 4) PARAMETER MIN TYP MAX UNITS From current-limit condition to FLT_ low 10 20 40 ms Turn-On Delay ROUT _= 10Ω, COUT_= 1µF, measured from ON_ high to 10% of VOUT_ 0.5 1.5 4.0 ms Output Rise Time ROUT_= 10Ω, COUT_= 1µF, measured from 10% to 90% of VOUT_ 3.5 Turn-Off Delay Time ROUT_ = 10Ω, COUT_ = 1µF, measured from ON_ low to 90% of VOUT_ 100 Output Fall Time ROUT_= 10Ω, COUT_ = 1µF, measured from 90% to 10% of VOUT_ 4.0 ms Thermal Shutdown Threshold 10°C hysteresis +160 °C Logic-Input High Voltage (ONA, ONB, ONC, SEL) VIN_ = 2.7V to 4.0V 1.6 VIN_ = 4.0V to 5.5V 2.0 Logic-Input Low Voltage (ONA, ONB, ONC, SEL) VIN_ = 2.7V to 4.0V 0.6 VIN_ = 4.0V to 5.5V 0.8 Current-Limit Fault-Blanking Timeout Period CONDITIONS Logic-Input Current FLT_ Output High Leakage Current SETI Output Voltage µs V +1 µA ISINK = 1mA 0.4 V VFLT_ = 5.5V 1 µA 600 SETI External Resistor Range 26.1kΩ sets 1.37A maximum current limit OUT_ Auto-Restart Current In latched-off state, VOUT_ = 0V 10 OUT_ Auto-Restart Threshold In latched-off state, VOUT_ rising 0.4 OUT_ Auto-Restart Delay Time 26 In latched-off state, VOUT_ > 1V 10 20 Reverse Current Detection Threshold Reverse Current Detection Blank Time 1000 V -1 FLT_ Output Low Voltage ms mV 60 kΩ 25 50 mA 0.5 0.6 V 40 ms 0.9 10 20 A 40 ms Note 4: Specifications to -40°C are guaranteed by design and characterization and not production tested. Note 5: The output voltage at which the device transitions from short-circuit current limit to continuous current limit. _______________________________________________________________________________________ 3 MAX1564 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (Circuit of Figure 1, VINA = VINB = VINC = VSEL = VONA = VONB = VONC = 5V, TA = +25°C, unless otherwise noted.) 1.0 0.8 0.6 50 40 30 0.4 20 0.2 10 46 56 1 2 3 4 5 -40 6 -15 10 35 60 RSETI (kΩ) INPUT VOLTAGE (V) TEMPERATURE (°C) STANDBY CURRENT vs. TEMPERATURE SWITCH OFF LEAKAGE CURRENT vs. TEMPERATURE REVERSE BLOCK LEAKAGE CURRENT vs. OUTPUT VOLTAGE 1 LEAKAGE CURRENT (µA) 3.0 2.5 2.0 1.5 1.0 LEAKAGE CURRENT (µA) 0.1 0.01 1 0.001 0 -15 10 35 60 -40 85 -15 10 35 60 TEMPERATURE (°C) TEMPERATURE (°C) NORMALIZED ON-RESISTANCE vs. TEMPERATURE CONTINUOUS CURRENT LIMIT vs. TEMPERATURE 1.45 CURRENT LIMIT (A) 1.00 0.75 0.50 -15 10 35 TEMPERATURE (°C) 60 85 4.1 4.8 5.5 OUTPUT RISE TIME vs. TEMPERATURE 1.35 1.30 1.25 1.20 1.15 VIN = 5.5V, RLOAD = 5Ω VIN = 5V, RLOAD = 5Ω VIN = 4.5V, RLOAD = 5Ω 9 8 7 6 5 VIN = 5V, NO LOAD VIN = 5.5V, NO LOAD VIN = 4.5V, NO LOAD 4 3 1.10 2 1.05 1 1.00 -40 3.4 10 OUTPUT RISE TIME (ms) 1.40 1.25 2.7 OUPUT VOLTAGE (V) 1.50 MAX1564 toc07 1.50 85 MAX1564 toc08 -40 10 VONA = VONB = VONC = 0V VOUT = 0V VONA = VONB = VONC = 0V 0.5 MAX1564 toc06 3.5 85 100 MAX1564 toc05 10 MAX1564 toc04 4.0 INPUT CURRENT (µA) 40 20 0 66 50 MAX1564 toc09 36 26 60 30 0 0 VIN = 4.5V 70 INPUT CURRENT (µA) 60 VIN = 5V VIN = 5.5V MAX1564 toc03 70 INPUT CURRENT (µA) 1.2 80 MAX1564 toc02 1.4 CURRENT LIMIT (A) 80 MAX1564 toc01 1.6 4 QUIESCENT SUPPLY CURRENT vs. TEMPERATURE QUIESCENT SUPPLY CURRENT vs. INPUT VOLTAGE CURRENT LIMIT vs. RSETI NORMALIZED RON MAX1564 Triple 1.2A USB Switch in 4mm x 4mm Thin QFN 0 -40 -15 10 35 TEMPERATURE (°C) 60 85 -40 -15 10 35 TEMPERATURE (°C) ________________________________________________________________________________________ 60 85 Triple 1.2A USB Switch in 4mm x 4mm Thin QFN (Circuit of Figure 1, VINA = VINB = VINC = VSEL = VONA = VONB = VONC = 5V, TA = +25°C, unless otherwise noted.) 3.0 2.8 2.6 2.4 RLOAD = 5Ω 2.2 225 VIN = 5.5V 22 VIN = 5.5V VIN = 5V VFLT_ (mV) 3.2 VIN = 4.5V 23 21 35 60 RPULLUP = 5kΩ 75 -40 85 -15 10 35 60 VIN = 5.5V 25 VIN = 4.5V 15 10 10 35 60 85 AUTO-RESTART CURRENT vs. INPUT VOLTAGE 28 AUTO-RESTART CURRENT (mA) MAX1564 toc13 35 VIN = 5V -15 TEMPERATURE (°C) AUTO-RESTART CURRENT vs. TEMPERATURE 40 20 -40 85 TEMPERATURE (°C) TEMPERATURE (°C) 30 VIN = 4.5V 125 19 MAX1564 toc14 10 VIN = 5V 20 17 -15 175 18 2.0 -40 MAX1564 toc12 24 3.4 275 MAX1564 toc11 VIN = 4.5V FAULT-BLANKING TIME (ms) VIN = 5V 25 MAX1564 toc10 VIN = 5.5V 3.6 AUTO-RESTART CURRENT (mA) OUTPUT FALL TIME (ms) 3.8 FLT_ LOW VOLTAGE vs. TEMPERATURE FAULT-BLANKING TIME vs. TEMPERATURE OUTPUT FALL TIME vs. TEMPERATURE 4.0 26 24 TA = +85°C 22 TA = +25°C 20 TA = -40°C 18 16 5 0 14 -40 -15 10 35 TEMPERATURE (°C) 60 85 2.7 3.4 4.1 4.8 5.5 INPUT VOLTAGE (V) _______________________________________________________________________________________ 5 MAX1564 Typical Operating Characteristics (continued) MAX1564 Triple 1.2A USB Switch in 4mm x 4mm Thin QFN Typical Operating Characteristics (continued) (Circuit of Figure 1, VINA = VINB = VINC = VSEL = VONA = VONB = VONC = 5V, TA = +25°C, unless otherwise noted.) SHORT-CIRCUIT RESPONSE INTO 0Ω OVERLOAD RESPONSE INTO 2.5Ω MAX1564 toc16 MAX1564 toc15 1A/div IOUT_ VOUT_ VFLT_ 5V/div 5V/div VOUT_ 2V/div VIN (AC-COUPLED) VIN (AC-COUPLED) 200mV/div 100mV/div 5V/div VFLT_ IOUT_ 1A/div 10ms/div 4ms/div SWITCH TURN-OFF TIME SWITCH TURN-ON TIME MAX1564 toc18 MAX1564 toc17 2V/div 2V/div VOUT_ VOUT_ 1V/div 1V/div VON_ VON_ RLOAD = 5Ω 1ms/div 6 RLOAD = 5Ω 1ms/div _______________________________________________________________________________________ Triple 1.2A USB Switch in 4mm x 4mm Thin QFN PIN NAME FUNCTION 1 INA Input Power Supply for OUTA. Provides power to OUTA. INA, INB, INC, and VCC must be connected together externally. Bypass with a 0.1µF capacitor to GND. Additional capacitors can be used as required. 2 VCC Input Power Supply for the MAX1564. Provides power to the IC. INA, INB, INC, and VCC must be connected together externally. 3 INB Input Power Supply for OUTB. Provides power to OUTB. INA, INB, INC, and VCC must be connected together externally. 4 INC Input Power Supply for OUTC. Provides power to OUTC. INA, INB, INC, and VCC must be connected together externally. 5 SEL Polarity Control Input. Selects the polarity of ONA, ONB, and ONC. Connect to VCC for active-high ON_ inputs. Connect to GND for active-low ON_ inputs. 6 SETI Current-Limit Program Input. Connect a resistor from SETI to GND in the 26kΩ to 60kΩ range. ILIM = 1.37A x 26.1kΩ / RSETI. 7 FLTB Fault-Indicator Output for Switch B. FLTB is an open-drain output that goes low when INB is below the UVLO threshold, or when switch B is in current limit for greater than 20ms, or when switch B is in thermal shutdown. 8 FLTC Fault Indicator Output for Switch C. FLTC is an open-drain output that goes low when INC is below the UVLO threshold, or when switch C is in current limit for greater than 20ms, or when switch C is in thermal shutdown. 9 OUTC Power Output for Switch C. OUTC is high impedance during shutdown. 10 OUTB Power Output for Switch B. OUTB is high impedance during shutdown. 11 GND Ground. Connect ground to the exposed pad directly under the IC. 12 OUTA Power Output for Switch A. OUTA is high impedance during shutdown. 13 FLTA Fault Indicator Output for Switch A. FLTA is an open-drain output that goes low when INA is below the UVLO threshold, or when switch A is in current limit for greater than 20ms, or when switch A is in thermal shutdown. 14 ONC Control Input for Switch C. ONC is active high when SEL is connected to VCC and active low when SEL is connected to GND. 15 ONB Control Input for Switch B. ONB is active high when SEL is connected to VCC and active low when SEL is connected to GND. 16 ONA Control Input for Switch A. ONA is active high when SEL is connected to VCC and active low when SEL is connected to GND. — EP Exposed Pad. Connect exposed pad to a large ground plane to improve thermal power dissipation. Detailed Description Undervoltage Lockout (UVLO) and Input Voltage Requirements The MAX1564 includes undervoltage-lockout (UVLO) circuitry to prevent erroneous switch operation when the input voltage is low during startup and brownout conditions. The IC is disabled when the input voltage is less than 2.5V (typ). FLT_ asserts low during a UVLO condition. Current-Limit Fault Protection The MAX1564 uses two methods to protect the circuit from overcurrent conditions. During an overcurrent event, the IC senses the switch output voltage and selects either continuous current limiting or short-circuit _______________________________________________________________________________________ 7 MAX1564 Pin Description MAX1564 Triple 1.2A USB Switch in 4mm x 4mm Thin QFN current limiting. When VOUT_ is greater than 1V, the device operates in continuous current-limit mode and limits output current to a user-programmable level. When VOUT_ is less than 1V, the device operates in short-circuit current-limit mode and pulses the output current to levels that are 30% (typ) higher than the selected current limit. When either fault condition persists for 20ms (typ), the output turns off and its fault flag is asserted. The output automatically restarts 20ms after the short or overload is removed. Auto-Restart Mode The MAX1564 detects short-circuit removal by sourcing 25mA from the output and monitoring the output voltage. When the voltage at the output exceeds 0.5V for 20ms, the fault flag resets, the output turns back on, and the 25mA current source turns off. Active loads are not expected to draw measurable current when supplied with less than 0.5V. The MAX1564 can also be reset from a fault by toggling the ON_ input for the offending channel. Reverse Current Blocking The USB specification does not allow an output device to source current back into the USB port. However, the MAX1564 is designed to safely power noncompliant devices. During normal operation with the channel enabled, the IC immediately turns off the switch if the output voltage rises above the input voltage sufficiently to create a reverse current in excess of 0.9A (typ). If the output voltage condition persists for longer than 20ms (typ), the switch remains off and the FLT_ flag is asserted. When any channel is disabled, the output is switched to a high-impedance state, blocking reverse current flow from the output back to the input. • The switch is in current-limit or short-circuit currentlimit mode after the fault-blanking period (20ms typ) expires. • The reverse current condition exists after the faultblanking period expires. The FLT_ output goes high impedance after a 20ms delay once the fault condition is removed. Ensure that the MAX1564 input bypass capacitance prevents glitches from triggering the FLT_ outputs. To differentiate large capacitive loads from short circuits or sustained overloads, the MAX1564 has an independent fault-blanking circuit for each switch. When a load transient causes the output to enter current limit, an internal counter monitors the duration of the fault. For load faults exceeding the 20ms fault-blanking time, the switch turns off, FLT_ asserts low, and the output enters auto-restart mode (see the Current-Limit Fault Protection and Auto-Restart Mode sections). Only current-limit and short-circuit faults are blanked. Thermaloverload faults and input voltages below the UVLO threshold immediately turn off the offending output and assert FLT_ low. Fault blanking allows the MAX1564 to handle USB loads that might not be fully compliant with USB specifications. The MAX1564 successfully powers USB R2 100kΩ 1 INPUT 2.75V TO 5.5V C1 0.1µF Thermal Shutdown Independent thermal shutdown of each channel permits delivering power to normal loads even if one load has a fault condition. The thermal limit does not have the 20ms fault blanking but sets the same fault latch that is used for other faults. Exiting this latched state is described in the Auto-Restart Mode section. 4 2 ACTIVE-HIGH/ ACTIVE-LOW SELECT INPUT Fault Indicators and Fault Blanking The MAX1564 provides an independent open-drain fault output (FLT_) for each switch. Connect FLT_ to IN_ through a 100kΩ pullup resistor for most applications. FLT_ asserts low when any of the following conditions occur: • The input voltage is below the UVLO threshold. • The switch junction temperature exceeds the +160°C thermal-shutdown temperature limit. 3 5 16 15 14 6 R1 26.1kΩ FLTA INA INB 13 R3 100kΩ MAX1564 FLTB INC 7 R4 100kΩ V CC FLTC OUTA SEL 8 12 C2 1µF ONA OUTB ONB 10 C3 1µF ONC SETI GND OUTC 9 11 Figure 1. Typical Application Circuit 8 _______________________________________________________________________________________ C4 1µF USB PORT A USB PORT B USB PORT C Triple 1.2A USB Switch in 4mm x 4mm Thin QFN Applications Information Setting the Current Limit The current limit for the MAX1564 is user programmable using the SETI input. Connect a resistor from SETI to GND (R1) to set the current limit. The value for R1 is calculated as: ILIMIT = 1.37A x 26.1kΩ / R1 R1 must be between 26kΩ and 60kΩ. Input Capacitor To limit the input voltage drop during momentary output load transients, connect a capacitor from IN_ to ground. A 0.1µF ceramic capacitor is required for local decoupling; however, higher capacitor values further reduce the voltage drop at the input. When driving inductive loads, a larger capacitance prevents voltage spikes from exceeding the MAX1564’s absolute maximum ratings. Output Capacitor A capacitor as large as 2000µF may be used on the output to smooth out transients and/or increase rise/fall times. Larger output capacitance may be used, but the resulting output charge time during startup may exceed the fault blanking period, resulting in a FLT_ flag. Driving Inductive Loads A wide variety of devices (mice, keyboards, cameras, and printers) typically connect to the USB port with cables, adding an inductive component to the load. This inductance causes the output voltage at the USB port to oscillate during a load step. The MAX1564 drives inductive loads; however, care must be taken to avoid exceeding the device’s absolute maximum ratings. Usually, the load inductance is relatively small, and the MAX1564’s input includes a substantial bulk capacitance from an upstream regulator, as well as local bypass capacitors, limiting overshoot. If severe ringing occurs because of large load inductance, clamp the MAX1564 outputs below +6V and above -0.3V. Turn-On and Turn-Off Behavior Slow turn-on and turn-off under normal operating conditions minimizes loading transients on the upstream power source. Rapid turn-off under fault conditions (thermal, short circuit, and UVLO) is done for maximum safety. Table 1. SEL/ON_ Inputs SEL ON_ High High OUT_ STATE Enabled High Low Disabled Low High Disabled Low Low Enabled SEL sets the active polarity of the logic inputs of the MAX1564. Connect ON_ to the same voltage as SEL to enable the respective OUT_ switch. Connect ON_ to the opposite voltage as SEL to disable the respective output (see Table 1). The output of a disabled switch enters a high-impedance state. Layout and Thermal Dissipation Keep all input/output traces as short as possible to reduce the effect of undesirable parasitic inductance and optimize the switch response time to output shortcircuit conditions. Place input and output capacitors no more than 5mm from device leads. Connect IN_ and OUT_ to the power bus with short traces. Wide power bus planes at IN_ and OUT_ provide superior heat dissipation as well. An active switch dissipates little power with minimal change in package temperature. Calculate the power dissipation for this condition as follows: P = IOUT_2 x RON At the normal operating current (IOUT_ = 0.5A) and the maximum on-resistance of the switch (100mΩ), the power dissipation is: P = (0.5A)2 x 0.100Ω = 25mW per switch The worst-case power dissipation occurs when the output current is just below the current-limit threshold with an output voltage greater than 1V. In this case, the power dissipated in each switch is the voltage drop across the switch multiplied by the current limit: P = ILIM x (VIN - VOUT) For a 5.5V input and 1V output, the maximum power dissipation per switch is: P = 1.54A x (5.5V - 1V) = 6.9W Because the package power dissipation is 1349mW, the MAX1564 die temperature may exceed the +160°C thermal-shutdown threshold, in which case the switch output shuts down until the junction temperature cools by 10°C. In a continuous overload condition, this causes a cyclical on/off situation. The duty cycle and period of this situation are strong functions of the ambient temperature and the PC board layout (see the Thermal Shutdown section). _______________________________________________________________________________________ 9 MAX1564 loads with additional bypass capacitance and/or large startup currents while protecting the upstream power source. No fault is reported if the output voltage rises nominal within the 20ms blanking period. MAX1564 Triple 1.2A USB Switch in 4mm x 4mm Thin QFN If the output current exceeds the current-limit threshold, or the output voltage is pulled below the short-circuit detect threshold, the MAX1564 enters a fault state after 20ms, at which point auto-restart mode is enabled and 25mA is sourced by the output. For a 5V input, OUT_ short circuited to GND, and auto-restart mode active, the power dissipation is as follows: Chip Information PROCESS: BiCMOS Package Information P = 0.025A x 5V = 0.125W For the latest package outline information and land patterns, go to www.maxim-ic.com/packages. Note that a “+”, “#”, or “-” in the package code indicates RoHS status only. Package drawings may show a different suffix character, but the drawing pertains to the package regardless of RoHS status. 10 PACKAGE TYPE PACKAGE CODE DOCUMENT NO. 16 TQFN-EP T1644-4 21-0139 ______________________________________________________________________________________ Triple 1.2A USB Switch in 4mm x 4mm Thin QFN PAGES CHANGED REVISION NUMBER REVISION DATE 0 4/01 Initial release — 1 2/10 Removed UL Certification Pending bullet from Features section 1 DESCRIPTION Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 11 © 2010 Maxim Integrated Products Maxim is a registered trademark of Maxim Integrated Products, Inc. MAX1564 Revision History