= Dual, USB 2.0 Full/Standby Power Controller with Supply Steering Preliminary Technical Data ADM1072 GENERAL DESCRIPTION FEATURES 500mA Load Current (100mA in Standby Mode) 135m⍀ On Resistance Switchable Current Limit 50µA Typical Quiescent Current 10nA Typical Shutdown Current 40nA Typical Switch Off Leakage Short-Circuit Protection Thermal Shutdown FLT Outputs Small, 16-Pin QSOP Package The ADM1072 is a logic controlled, dual P-channel switch with low on resistance and a built-in current limiter, capable of sourcing up to 1A from supply voltages between 2.7V and 5.5V. In addition to logic inputs that switch each channel on and off, the device has a standby input that switches the output current limit, making it ideal for use with USB peripherals. In normal operating mode and Standby mode the output current is typically limited to 500mA and 100mA respectively, as outlined by the USB2.0 Specification. This allows the system power supply to be protected against short-circuits and surge currents in peripheral USB devices powered via the ADM1072. Over-current and over-temperature conditions are signalled by a fault output (FLT) for each channel. APPLICATIONS Desktop Computers Palmtop Computers Notebook Computers Hand-Held Instruments Universal Serial Bus (USB) The ADM1072 also offers low quiescent current of typically 50µA and shutdown current of typically 10nA. 1A MAIN FET MAIN_IN (2.7V TO 5.5V) 2 3 1A MIRROR FET 22µF 14 15 STBY_IN (2.7V TO 5.5V) 0.2A MAIN FET 5 1 12 4 0.2A MIRROR FET 4.7µF 120µF MIRROR AMPLIFIER TO CHANNEL 2 O N 1 11 OP1 VPULLUP 0 TO 5.5V CONTROL LOGIC CURRENT LIMIT AMPLIFIER RPULLUP 10k⍀ TO 100k⍀ 1.24V BANDGAP REFERENCE FLT1 UNDERVOLTAGE SENSOR STBY 9 TEMPERATURE SENSOR 6 ADM1072 CURRENT SETTING RESISTOR VPULLUP 0 TO 5.5V OVERTEMP RPULLUP 10k⍀ TO 100k⍀ GND 8 7 TO CHANNEL 2 O N 2 10 TO CHANNEL 2 TO CHANNEL 2 CHANNEL 2 IS IDENTICAL TO CHANNEL 1 FLT2 13 OP2 16 120µF FUNCTIONAL BLOCK DIAGRAM Rev. PrE 1/02 Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781/329-4700 World Wide Web Site: http://www.analog.com Fax: 781/326-8703 © Analog Devices, Inc., 2002 ADM1072–SPECIFICATIONS (Specification for either channel 1 or channel 2, VIN = +5.0V, TA = -40 to +85oC, unless otherwise noted.) Parameter Min Operating Voltage Range +2.7 Typ µA ON1,ON2 = VIN = 5.5V, VOUT = 0V 2.3 2.6 V VSTBY_IN, Rising Edge, 1% Hysteresis ? ? 135 ? m⍀ m⍀ VIN = 4.75V VIN = 3.0V 1.0 200 1.2 240 A mA STBY Low Note 1 STBY High Note 1 0.8 V VIN = 2.7V to 5.5V V VIN = 2.7V to 5.5V ±1 µA VON, VSTBY = 5.5V 0.4 V ISINK = 1mA 1 µA VFAULT = 5.5V 4 4 ms ms VIN = 5V, IOUT = 500mA VIN = 3V, IOUT = 500mA 20 µs VIN = 5V, IOUT = 500mA 0.01 NOMINAL CURRENT-LIMIT Full Power Mode Standby Mode 0.8 160 ON1,ON2, STBY Input Low Voltage, VIL ON1,ON2, STBY Input High Voltage, VIH 2.4 ON1,ON2, STBY Input Leakage 0.01 FLT1,FLT2 Logic Output Low Voltage FLT1,FLT2 Output High Leakage Current 0.05 Turn-On Time Turn-Off Time Volts 2 Shutdown Supply Current (Total Device) On Resistance +5.5 ? Test Conditions/Comments VIN = 5V, ON1,ON2 = GND, IOUT = 0A 50 2.0 Units µA Quiescent Current (Total Device) Undervoltage Lockout Max ? Notes 1 Current limit is specified with VOUT = 4.5V. 2 Guaranteed by design. Derived from the ISET current ratio, current-limit amplifier and internal set resistor accuraciues. 3 Tested with IOUT = 200mA and VSET adjusted until (VIN - VOUT) 艌 0.8V. 4 Specifications to -40oC are guaranteed by design, not tested. –2– Rev. PrE 1/02 ADM1072 ABSOLUTE MAXIMUM RATINGS* (TA = +25°C unless otherwise noted) MAIN_IN to GND . . . . . . . . . . . . . . . . . . . . . . –0.3V to +6V ON1,ON1,FLT1, FLT2 to GND . . . . . . . . . . . –0.3V to +6V OP1,OP2 to GND . . . . . . . . . . . . . . . . +0.3 V to (VIN + 0.3V) Maximum Switch Current Full Power Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1A Standby Power Mode . . . . . . . . . . . . . . . . . . . . . . . . 200mA Continuous Power Dissipation (TA = +70oC) . . . . . 667mW QSOP (derate 8.3mW/oC above +70oC) Operating Temperature Range Industrial (A Version) . . . . . . . . . . . . . . . –40°C to +85°C Storage Temperature Range . . . . . . . . . . . –65°C to +150°C Lead Temperature (Soldering, 10 sec) . . . . . . . . . . . +300°C *This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. O P1 1 16 O P2 M AIN _IN 2 15 M AIN _IN M AIN _IN 3 14 M AIN _IN O P1 4 AD M 10 72 13 O P2 S T BY _IN 5 T O P V IE W (No t to S cale) 12 S T BY _IN F LT 1 6 11 O N 1 F LT 2 7 10 O N 2 G ND 8 9 S T BY Pin Configuration THERMAL CHARACTERISTICS 16-Pin QSOP Package: qJA = 105°C/Watt, qJC = 40°C/Watt ORDERING GUIDE Model Temperature Range Package Description Package Option ADM1072ARQ -40°C to +85°C 16-Pin QSOP RQ-16 Package PIN FUNCTION DESCRIPTION Pin Mnemonic Function 2, 3, 14, 15 MAIN_IN Input to MAIN P-channel MOSFET source (both channels). Bypass MAIN_IN with a 22µF capacitor to ground. 5, 12 STBY_IN Input to Standby P-channel MOSFET source (both channels) and supply to chip circuitry. Bypass STBY_IN with a 4.7µF capacitor to ground. 1, 4 OP1 Output from channel 1, P-channel MOSFET drains. Bypass OP1 with a 120µF capacitor to ground. 13, 16 OP2 Output from channel 2, P-channel MOSFET drains. Bypass OP2 with a 120µF capacitor to ground. 6 FLT1 Open-Drain Digital Output. FLT1 goes low when the channel 1 current limit is exceeded for 10mS or the die temperature exceeds +150oC. During startup, FLT1 remains low for the turn-on time. 7 FLT2 Open-Drain Digital Output. FLT2 goes low when the channel 2 current limit is exceeded for 10mS or the die temperature exceeds +150oC. During startup, FLT2 remains low for the turn-on time. 8 GND Ground pin for all chip circuits. 9 STBY Digital Input. Active high standby mode input. STBY = 0 sets normal operating mode with 500mA current limit. STBY = 1 sets standby mode with 100mA current limit. 10 ON2 Digital Input. Active-low switch enable for channel 2 (logic 0 turns the switch on). 11 ON1 Digital Input. Active-low switch enable for channel 1 (logic 0 turns the switch on). Rev. PrE 1/02 –3– ADM1072 Typical Performance Curves G N I IT A AW A T DA G N I IT A AW A T DA Figure 4. Off-Switch Current vs. Temperature Figure 1. Quiescent Current vs. Input Voltage G N I IT A AW A T DA G N I IT A AW A T DA Figure 5. Normalized On Resistance vs. Temperature Figure 2. Quiescent Current vs. Temperature G N I IT A AW A T DA G N I IT A AW A T DA Figure 6. IOUT/ISET Ratio vs Switch Current Figure 3. Off-Supply Current vs. Temperature –4– Rev. PrE 1/02 ADM1072 Typical Performance Curves G N I IT A AW A T DA G N I IT A AW A T DA Figure 7. Normalized Output Current vs. Output Voltage Figure 10. Fast Current-Limit Response G N I IT A AW A T DA G N I IT A AW A T DA Figure 8. Turn-On Time vs. Temperature Figure 11. Slow Current-Limit Response G N I IT A AW A T DA G N I IT A AW A T DA Figure 9. Turn-Off Time vs. Temperature Rev. PrE 1/02 Figure 12. Load Transient Response –5– ADM1072 Typical Performance Curves G N I IT A AW A T DA G N I IT A AW A T DA Figure 13. Switch Turn-On Time Figure 15. USB Circuit Output Rise Time G N I IT A AW A T DA G N I IT A AW A T DA Figure 14. Switch Turn-Off Time Figure 16 USB Circuit output Fall Time –6– Rev. PrE 1/02 ADM1072 FUNCTIONAL DESCRIPTION SHORT-CIRCUIT PROTECTION The ADM1072 is a dual, logic-controlled P-channel switch. Each channel of the ADM1072 comprises two P-channel switches. The source of one switch is connected to the “MAIN_IN” input pins and can switch up to 1A. The second switch is conected to the “STBY_IN” pins and can switch up to 200mA. The device is rated to provide 500mA continuously in full power mode and 100mA continuously in STBY mode. The STBY_IN inputs also provide the power for the chip circuitry and so must be connected to a supply at all times. When STBY is low the MAIN switch is active and when STBY is high the Standby switch is active. Each channel is individually controlled by an active-low logic input ON1 (pin 11) and ON2 (pin 10). When either ON1 or ON2 is low, the internal circuitry of the ADM1072 is powered up and the output of the corresponding current-limit amplifier is low, providing gate drive to the switching FET, thus turning it on. When both ON inputs are high, the internal circuitry is powered down and the current consumption is typically 10nA. The proportional relationship between the main FET and the mirror FET is only maintained down to an output voltage of about 1.6V. Below this voltage the output current is limited to approximately 1.2 x ILIMIT. In the event of a high dV/dt across the switching FET during a short-circuit, the switch will turn off and disconnect the input from the output. The switch is then turned on slowly with the current limited to the short-circuit value. THERMAL SHUTDOWN The thermal shutdown operates when the die temperature exceeds +150oC, turning off both channels. The thermal shutdown circuit has built-in hysteresis of 10oC, so the switch will not turn on again until the die temperature falls to +140oC. If the fault condition is not removed, the switch will pulse on and off as the temperature cycles between these limits. UNDERVOLTAGE LOCKOUT It should be noted that the ADM1072 is not a bi-directional switch, so VIN must always be higher than VOUT. The undervoltage sensor monitors the input supply voltage (ie) the voltage on STBY_IN. The outputs will not turn on until the supply voltage is sufficient for the chip circuits to operate reliably. Undervoltage lockout occurs at between 2.0 and 2.6V. TABLE 1. Truth Table for ON1, ON2 and STBY ON1 ON2 STBY Channel 1 Channel 2 0 0 0 500mA 500mA FLT OUTPUTS 0 0 1 100mA 100mA 0 1 0 500mA OFF 0 1 1 100mA OFF 1 0 0 OFF 500mA The ADM1072 has active-low fault outputs for each channel, FLT1 (pin 6) and FLT2 (pin 7). If the current limit is exceeded for greater than 10mS, the corresponding FLT output will pull low. If the thermal shutdown is activated, both FLT outputs will pull low. The FLT outputs are open-drain and require a pullup resistor of between 10k⍀ and 100k⍀. Several FLT outputs may be wire-OR’d to form a common interrupt line, as shown in Figure 17 or FLT outputs may be wire-OR’d to an existing interrupt line that has a resistive pullup. 1 0 1 OFF 100mA V P U L LU P 1 1 X BOTH SHUT DOWN RP ULL UP X = don’t care IN T CURRENT LIMIT When either the Main or Standby switch is turned on a smaller mirror switch passes a proportionate current equal to IOUT/ 1000. The mirror amplifier maintains this relationship by keeping the drain of the mirror FET at the same voltage as the main FET, and drives the mirror current through an internal current-limit resistor, which is connected between the noninverting input of the current limit amplifier and ground. An on-chip bandgap reference of 1.24V is connected to the inverting input of the current-limit amplifier. When the load current exceeds the preset limit, the voltage across the currentlimit resistor exceeds 1.24V and the output voltage of the current-limit amplifier rises, reducing the gate drive to the FETs. F LT 1 AD M 1 072 F LT 2 AD M 1 072 F LT 2 F LT 1 AD M 1072 F LT 2 Figure 17. Wire Or’ing FAULT Outputs During startup, the FLT output goes low for the turn-on time. By selecting between the Standby and Main FETs and their associated mirror FETs, the STBY input allows the two different values of current limit specified by USB2.0 to be selected. This feature is particularly useful when driving USB peripherals from a host system such as a PC that can go into a powersaving mode, since it limits the current that the peripherals can attempt to draw from the host power supply. Rev. PrE 1/02 F LT 1 –7– ADM1072 APPLICATIONS INFORMATION INPUT FILTERING To prevent the input voltage being pulled below the minimum operating voltage under transient short-circuit conditions, before the current limit has had time to operate, a reservoir capacitor should be connected from MAIN_IN to GND. This does not need to be large, but should have a low ESR. A value of around 10 - 22µF is suitable. Larger values will reduce the voltage drop still further. The STBY_IN input requires a proportionately smaller value, typically 2.2 to 4.7µF. OUTPUT CAPACITANCE 120µF capacitors should be connected between OP1 and OP2 and GND to prevent the back e.m.f. of parasitic inductance from pulling OP1 and OP2 below ground during turn-off and to provide adequate turn- on current for Universal Serial Bus (USB) applications that are hot plugged to OP! or OP2. This causes the output rise and fall times to be longer, as shown in the typical operating characteristics, but does not affect the turn-off time of the ADM1072 itself. LAYOUT CONSIDERATIONS Printed circuit board tracks to and from the ADM1072 should be as thick and as short as possible to minimise parasitic inductance and take full advantage of the fast response time of the switch. Input and output capacitors should be placed as close to the device as possible (less than 5mm). THERMAL CONSIDERATIONS Under normal operating conditions, the worst-case power dissipation will be 135mW with the 135m⍀ on resistance and 3V supply (W = (1A)2 ⫻ 0.135⍀). The package is capable of handling and dissipating this power, but heat dissipation can further be improved by providing a large area of copper in contact with the device pins, particularly MAIN_IN and OP1,OP2. OUTLINE DIMENSIONS Dimensions shown in inches and (mm). 16-Pin QSOP Package (RQ-16) 0.197 (5.00) 0.189 (4.80) 9 16 0.244 (6.20) 0.157 (3.99) 0.228 (5.79) 0.150 (3.81) 1 8 P IN 1 0.069 (1.75) 0.059 (1.50) M AX 0.010 (0.25) 0.004 (0.10) 0.053 (1.35) 0.025 (0.64) BS C 0.012 (0.30) 0.008 (0.20) S EAT ING P LAN E –8– 0.010 (0.20) 0.007 (0.18) 8& 0& 0.050 (1.27) 0.016 (0.41) Rev. PrE 1/02