MIC2012 Micrel MIC2012/MIC2072 USB Power Controller Advance Information General Description Features The MIC2012 is a dual channel USB power switch designed to support the power distribution requirements for USB Wakeup from the ACPI S3 state. The MIC2012 will directly switch its two outputs between a 5V main supply and a 5V auxiliary supply normally provided in ATX style power supplies. The MIC2012 will adjust its current-limit threshold according to the ACPI state it is in. In the normal active S0 state the current-limit is set at 500mA minimum per channel satisfying the USB continuous output current specification. In the S3 state the current-limit can be reduced to only 100mA per channel to minimize the current that is supplied by the auxiliary supply thereby ensuring that voltage regulation is maintained even during fault conditions. The MIC2012 provides make-before-break switching to ensure glitch-free transitions between the S3 and S0 states. Each channel is also thermally isolated from the other so that a fault in one channel does not effect the other. FAULT status output signals are also provided indicating overcurrent and thermal shutdown conditions. The MIC2072 option latches the output off upon detecting an overcurrent condition for more than 5ms minimum. The output can be reset by either toggling the EN inputs of the MIC2072-1, -2 or by removing the load. Latching the output off provides a circuit breaker mode of operation which reduces power consumption during fault conditions. • Compliant to USB power distribution specifications • Two completely independent switches • Integrated switching matrix supports ACPI S0/S3 state transitions without external FET circuits • Make-before-break switching ensures glitch-free transitions • No back-feed of auxiliary supply onto main supply during standby mode • Bi-level current-limit preserves auxiliary supply voltage regulation in standby mode • Thermally isolated channels • Thermal shutdown protection • Fault status outputs with filter prevents false assertions during hot-plug events • Latched thermal shutdown options with auto-reset (MIC2072) • Undervoltage lockout Applications • • • • • Desktop PCs Notebook PCs Notebook Docking stations LAN Servers PC Motherboards Typical Application ATX Power Supply 5V MAIN VBUS 5V STANDBY D+ MIC2012P MAIN AUX S3 Control D– OUT1 OUT2 Downstream USB Port 1 GND 100µF S3# FAULT1# VBUS D+ FAULT2# GND 100µF 82801AA or Equivalent D– Downstream USB Port 2 GND SLP S3# SLP S5# OC0 OC1 Overcurrent Port 1 Overcurrent Port 1 Figure 1. USB Wakeup with Control Input Micrel, Inc. • 1849 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 944-0970 • http://www.micrel.com September 2000 1 MIC2012/2072 MIC2012 Micrel Ordering Information Part Number Enable Fault Output MIC2012CM n/a MIC2012PCM* Circuit Breaker Function Temperature Range Package Open-Drain 0°C to +70°C 8-lead SOIC n/a Internal Pull-Up 0°C to +70°C 8-lead SOIC MIC2012-1CQS* Active High Open-Drain 0°C to +70°C 16-lead QSOP MIC2012-1PCQS* Active High Internal Pull-Up 0°C to +70°C 16-lead QSOP MIC2012-2CQS* Active Low Open-Drain 0°C to +70°C 16-lead QSOP MIC2012-2PCQS* Active Low Internal Pull-Up 0°C to +70°C 16-lead QSOP MIC2072CM* n/a Open-Drain ✓ 0°C to +70°C 8-lead SOIC MIC2072PCM* n/a Internal Pull-Up ✓ 0°C to +70°C 8-lead SOIC MIC2072-1CQS* Active High Open-Drain ✓ 0°C to +70°C 16-lead QSOP MIC2072-1PCQS* Active High Internal Pull-Up ✓ 0°C to +70°C 16-lead QSOP MIC2072-2CQS Active Low Open-Drain ✓ 0°C to +70°C 16-lead QSOP MIC2072-2PCQS* Active Low Internal Pull-Up ✓ 0°C to +70°C 16-lead QSOP * Contact factory for availability. Pin Configuration FAULT1 1 FAULT1 1 8 FAULT2 S3# 2 7 OUT1 AUX 3 6 MAIN GND 4 5 OUT2 8-Pin SOIC (M) 16 FAULT2 EN1 2 15 EN2 S3# 3 14 OUT1 NC 4 13 OUT1 AUX 5 12 MAIN NC 6 11 MAIN NC 7 10 OUT2 GND 8 9 OUT2 16-Pin QSOP (QS) MIC2012/2072 2 September 2000 MIC2012 Micrel Pin Description Pin Number (MIC2012) Pin Number (MIC2012-1, -2) Pin Name 1 1 FAULT1 n/a 2 EN1 Enable (Input): Channel 1, active-high (–1) or active-low (–2). Toggling this input also resets the latched output of the MIC2072. 2 3 S3# Control (Input): When this input is HIGH, the MAIN inputs are connected to OUT1 and OUT2 via 100mΩ MOSFET switches. When this input is LOW the AUX inputs are connected to OUT1 and OUT2 via 500mΩ MOSFET switches. 3 5 AUX Auxiliary 5V Supply (Input): Also used as power supply for internal circuitry. n/a 4, 6, 7 NC No Connection: This pin may be connected to other pins without restriction. 4 8 GND Ground 5 9, 10 OUT2 Channel 2 (Output): For MIC2012-1, -2 both pins must be externally connected together. 6 11, 12 MAIN 5V Main Supply (Input): All MAIN inputs must be connected together externally. 7 13, 14 OUT1 Channel 1 (Output): For MIC2012-1, -2 both pins must be externally connected together. n/a 15 EN2 Enable (Input): Channel 2, active-high (–1) or active-low (–2). Toggling this input also resets the latched output of the MIC2072. 8 16 FAULT2 Fault Status (Output): Internal pull-up or open-drain. Asserted LOW when Channel 2 is in a thermal shutdown state or overcurrent condition for more than 5ms. MIC2072 latches this output in its asserted state upon an overcurrent condition. Toggling EN2 or removing the load will reset the circuit breaker latch and deassert FAULT2. September 2000 Pin Function Fault Status (Output): Internal pull-up or open-drain. Asserted LOW when Channel is in a thermal shutdown state or overcurrent condition for more than 5ms. MIC2072 latches this output in its asserted state upon an overcurrent condition. Toggling EN1 or removing the load will reset the circuit breaker latch and deassert FAULT1. 3 MIC2012/2072 MIC2012 Micrel Absolute Maximum Ratings (Note 1, Note 4) Operating Ratings (Note 2) Supply Voltage (VIN, VMAIN, VAUX) ................... –0.3V to 6V EN1, EN2, S3# Input Pins ................................ –0.3V to 6V FAULT#, OUT1, OUT2 Output Pins ................. –0.3V to 6V FAULT Output Current ............................................... 25mA ESD Rating, Note 3 ...................................................... 2kV Supply Voltage (VMAIN, VAUX) ..................... +4.5V to +5.5V Ambient Temperature (TA) ........................... –0°C to +70°C Junction Temperature (TJ) ....................... Internally Limited Package Thermal Resistance QSOP (θJA) ....................................................... 163°C/W SOIC (θJA) ......................................................... 160°C/W Electrical Characteristics VMAIN = 5V; AUX = 5V; TA = 25°C; unless noted Symbol Parameter VMAIN MAIN Supply Voltage IMAIN (ON) MAIN Supply Current Switches On Note 5 IMAIN (OFF) MAIN Supply Current Switches Off S3# = 1, no load Note 5, (MIC20x2-1, MIC20x2-2 only) ILEAK MAIN Reverse Leakage Current, VAUX AUX Supply Voltage IAUX ON AUX Supply Current, both switches on, Note 5 No load S3# = 0 IAUX OFF AUX Supply Current, switches off. (MIC20x2-1, MIC20x2-2 only) No load S3# = 0 VUV/AUX AUX Undervoltage Lockout Threshold VAUX increasing VAUX decreasing VHYS AUX Undervoltage Lockout Hysteresis RDSMAIN MAIN On-Resistance, Each Output S3# = 1, IOUT = 500mA 100 140 mΩ RDSAUX AUX On-Resistance, Each Output S3# = 0, IOUT = 100mA 500 700 mΩ ILIMIT(MAIN) MAIN Current-Limit Threshold S3# = 1, VOUT = 4.0V, ramped load 0.5 1.25 A MAIN Short-Circuit Current-Limit VOUT = 0V 0.5 1.25 A AUXCurrent-Limit Threshold S3# = 0, VOUT = 4.0V, ramped load 105 195 mA AUX Short-Circuit Current-Limit VOUT = 0V, COUT = 100µF S3#, EN1, EN2. Input Threshold Voltage (EN1, EN2, for MIC20x2-x only) High-to-Low transition ILIMIT(AUX) VTH Condition Min Typ Max Units 4.5 5.0 5.5 V 16 22 µA 5 µA +10 µA 5.0 5.5 V .6 1 mA 5 µA 4.0 3.8 V V S3# = 1, no load S3# = 0, both switches ON, VMAIN = 0V –10 4.5 3.5 3.3 3.7 3.5 200 .8 Low-to-High transition 150 mV 80 mA 1.5 V 1.7 2.0 V VHYS EN1, EN2 and S3# Input Hysteresis (EN1, EN2, for MIC20x2-x only) IIN S3#, EN1, EN2 Input Current (EN1, EN2, for MIC20x2-x only) VS3/EN = 5V, 0V –1 1 µA IOFF OUT1, OUT2 Leakage Current (MIC2012-x, MIC2072-x only) Outputs are off, VOUT = 0 –10 10 µA Pull-Up Current During Latched Output State (MIC2072-1, -2) Outputs latched off MIC2012/2072 200 4 1 mV mA September 2000 MIC2012 Micrel Symbol Parameter Condition VTH LATCH Latch Reset Threshold (MIC2072, MIC2072-x only) VOUT Rising Min Minimum Output Slew Rate to Reset Latch (MIC2072, MIC2072-x only), Note 6 Typ Max Units 1.95 V .4 V/s 140 120 160 150 °C °C °C °C Overtemperature Threshold TJ increasing, single channel TJ decreasing, single channel TJ increasing, both channels TJ decreasing, both channels VOL FAULT Output Low Voltage IFAULT = 5mA VOH FAULT Output High Voltage (MIC2012-1P,-2P),(MIC2072-1P,-2P) IFAULT = –20µA FAULT Output Off Current (Not Applicable to 'P' Options) VFAULT = 5V TH MAIN to S3# Hold Time, Note 6 Figure 5 5 ms TS MAIN to S3# Set-up Time, Note 6 Figure 5 0 ms tDLY FAULT Delay Filter Response Time (Overcurrent only), Note 7 Output shorted to ground, Figure 4 5 tOC Overcurrent Response Time Output shorted to ground, Figure 4 MAIN output AUX output 2 2 µs µs 0.2 4 V V .2 10 10 20 µA ms tON(MAIN) MAIN Output Turn-On Time RL = 10Ω, CL = 1µF, Figure 3 2 ms tOFF(MAIN) MAIN Output Turn-Off Time (MIC20x2-x only) RL = 10Ω, CL = 1µF, Figure 3 35 µs tr(MAIN) MAIN Output Rise Time RL = 10Ω, CL = 1µF, Figure 3 2 ms tf(MAIN) MAIN Output Fall Time (MIC20x2-x only) RL = 10Ω, CL = 1µF, Figure 3 32 µs tON(AUX) AUX Output Turn-On Time RL = 50Ω, CL = 1µF, Figure 3 0.6 ms tOFF(AUX) AUX Output Turn-Off Time (MIC20x2-x only) RL = 50Ω, CL = 1µF, Figure 3 120 µs tr(AUX) AUX Output Rise Time RL = 50Ω, CL = 1µF, Figure 3 0.5 ms tf(AUX) AUX Output Fall Time (MIC20x2-x only) RL = 50Ω, CL = 1µF, Figure 3 115 µs tXMA MAIN to AUX Cross Conduction Time, Note 8 S3# transition to 0 5 7.5 ms tXAM AUX to MAIN Cross Conduction Time, Note 8 S3# transition to 1 5 7.5 ms Note 1. Exceeding the absolute maximum rating may damage the device. Note 2. The device is not guaranteed to function outside its operating rating. Note 3. Devices are ESD sensitive. Handling precautions recommended. Human body model, 1.5k in series with 100pF. Note 4. All voltages are referenced to ground. Note 5. For MIC20x2-1(P) OFF occurs when VEN < 0.8V and ON occurs when VEN > 2.4V. For MIC20x2-2(P) OFF occurs when VEN > 2.4V and ON occurs when VEN < 0.8V. Note 6. Guaranteed by design. Not production tested. Note 7. Assumes only one channel in current-limit. Delay circuitry is shared among channels so it is possible for tDLY to be 40ms max if one channel enters current-limit as the other is about to time-out. Note 8. Cross conduction time is the duration in which both MAIN and AUX internal switches are on subsequent to S3# transitioning. September 2000 5 MIC2012/2072 MIC2012 Micrel Test Circuit VOUT Device Under OUT Test IOUT RL CL tr tf 90% VOUT 10% MIC2012/2072 90% 10% 6 September 2000 MIC2012 Micrel Timing Diagrams 50% VEN tOFF tON 90% VOUT 10% Figure 2. MIC2012/72-1 50% VEN tOFF tON 90% VOUT 10% Figure 3. MIC2012/72-2 Output shorted to ground VOUT IOUT ILIMIT tOC FAULT# tDLY Figure 4. Overcurrent Response Timing tH tS MAIN S3# 1.5V 1.5V Figure 5. MAIN to S3# Timing September 2000 7 MIC2012/2072 MIC2012 Micrel Functional Diagram MAIN Current Limit MAIN FET Charge Pump + Gate Control EN OUT AUX FET AUX S3# Current Limit Thermal Sense AUX * 'P' options only Latch 10ms Timer * /FAULT *MIC2070-1/2 Only To Other Channel TJ = junction temperature TA = ambient temperature θJA = is the thermal resistance of the package Current Sensing and Limiting The current-limit thresholds are preset internally for each state. The preset level prevents damage to the device and external load but still allows a minimum current of 100mA or 500mA to be delivered to the load depending on the state of the device according to the S3# input. When S3# is LOW the current-limit is set at 100mA minimum. When S3# is HIGH the current-limit is set at 500mA minimum. Should an over-current condition last longer than tDLY, the MIC2072 will latch the faulty output off. The output will remain off until either the load is removed or the EN signal (MIC20721, -2) is toggled. When the MIC2072 enters a latched output condition a 1mA pull-up current source is activated. This provides a way to automatically reset the output once the load is removed without the need to toggle the enable input such as in the MIC2072. Please refer to Figure 7 for timing details. The MIC2012 will automatically reset its output when the die temperature cools down to 120°C. The MIC2012 output and FAULT signal will continue to cycle on and off until the device is disabled or the fault is removed. Figure 6 depicts typical timing. Depending on PCB layout, package, ambient temperature, etc., it may take several hundred milliseconds from the incidence of the fault to the output MOSFET being shut off. This time duration will be shortest in the case of a dead short on the output. Functional Description The MIC2012/2072 are designed to support the power distribution requirements for USB wakeup from the ACPI S3 state. It integrates two independent channels under control of input S3#. When S3# is asserted LOW (S3 state) the MIC2012/ 2072 will switch a 500mΩ, 100mA MOSFET switch from the AUX input to each of its two outputs. Conversely when the S3# input is HIGH (S0 state) the MIC2012/72 will switch a 100mΩ, 500mA MOSFET switch from the MAIN input to each of its two outputs. The lower current limit during the ACPI S3 state helps to ensure that the standby supply maintains regulation even during fault conditions. Thermal Shutdown Thermal shutdown is employed to protect the device from damage should the die temperature exceed safe margins due mainly to short circuit faults. Thermal shutdown shuts off the output MOSFET and asserts the FAULT output if the die temperature reaches 140°C and the overheated channel is in current limit. The other channel is not affected. If, however, the die temperature exceeds 160°C, both channels will be shut off even if neither channel is in current limit. Power Dissipation The device’s junction temperature depends on several factors such as the load, PCB layout, ambient temperature and package type. The power dissipated in each channel is PD = RDS(on) × IOUT2 where RDS(on) is the on-resistance of the internal MOSFETs and IOUT is the continuous output current. Total power dissipation of the device will be the summation of PD for both channels. To relate this to junction temperature, the following equation can be used: TJ = PD × θJA + TA where: MIC2012/2072 8 September 2000 MIC2012 Micrel Fault Status Output The FAULT signal is an active-low output with an open-drain or weak pull-up configuration. FAULT is asserted (active-low) when either an overcurrent or thermal shutdown condition occurs. In the case of an overcurrent condition, FAULT will be asserted only after the flag response delay time, tDLY, has elapsed. This ensures that FAULT is asserted only upon valid overcurrent conditions and that erroneous error reporting is eliminated. For example, false overcurrent conditions can occur during hot-plug events when a highly capacitive load is connected and causes a high transient inrush current that exceeds the current-limit threshold. The FAULT response delay time tDLY is typically 10ms. Undervoltage Lockout Undervoltage lockout (UVLO) prevents the output MOSFET from turning on until the AUX input exceeds approximately 3.5V. UVLO ensures that the output MOSFETs remain off to prevent high transient inrush current due to stray or bulk load capacitance. This helps to ensure that the power supply voltage regulation is preserved and also prevents possible damage to sensitive components. Overcurrent Fault EN (MIC2010-2) VOUT FAULT Thermal Shutdown Reached Figure 6. MIC2012 System Timing Overcurrent Fault EN (MIC2070-2) VOUT FAULT Load Removed– Output Reset Figure 7. MIC2072 System Timing— Output Resets When Load is Removed September 2000 9 MIC2012/2072 MIC2012 Micrel Package Information PIN 1 DIMENSIONS: INCHES (MM) 0.157 (3.99) 0.150 (3.81) 0.009 (0.2286) REF 0.025 (0.635) BSC 0.0098 (0.249) 0.0040 (0.102) 0.012 (0.30) 0.008 (0.20) 0.0098 (0.249) 0.0075 (0.190) 0.196 (4.98) 0.189 (4.80) SEATING 0.0688 (1.748) PLANE 0.0532 (1.351) 45° 8° 0° 0.050 (1.27) 0.016 (0.40) 0.2284 (5.801) 0.2240 (5.690) 16-Pin QSOP (QS) 0.026 (0.65) MAX) PIN 1 0.157 (3.99) 0.150 (3.81) DIMENSIONS: INCHES (MM) 0.020 (0.51) 0.013 (0.33) 0.050 (1.27) TYP 0.064 (1.63) 0.045 (1.14) 45° 0.0098 (0.249) 0.0040 (0.102) 0.197 (5.0) 0.189 (4.8) 0°–8° SEATING PLANE 0.010 (0.25) 0.007 (0.18) 0.050 (1.27) 0.016 (0.40) 0.244 (6.20) 0.228 (5.79) 8-Pin SOIC (M) MICREL INC. 1849 FORTUNE DRIVE SAN JOSE, CA 95131 TEL + 1 (408) 944-0800 FAX + 1 (408) 944-0970 WEB USA http://www.micrel.com This information is believed to be accurate and reliable, however no responsibility is assumed by Micrel for its use nor for any infringement of patents or other rights of third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent right of Micrel Inc. © 2000 Micrel Incorporated MIC2012/2072 10 September 2000