MIC2551A-2.5 Micrel, Inc. MIC2551A-2.5 USB Transceiver General Description Features The MIC2551A is a single chip transceiver that complies with the physical layer specifications of the Universal Serial Bus (USB) 2.0. It supports both full speed (12Mbps) and low speed (1.5Mbps) operation and introduces superior edge rate control, producing crisper eye diagrams. This in turn, eases the task of passing USB compliance testing. A unique, patented, dual supply voltage operation allows the MIC2551A to reference the system I/F I/O signals to a supply voltage down to 1.6V while independently powered by the USB VBUS. This reduces system operating current and allows the system to operate at its core voltage without additional buffering logic. MIC2551A-2.5 is differentiated from MIC2551A by a smaller space saving MLF® package (2.5mm × 2.5mm) and ±15kV ESD protection which eliminates the need for separate ESD protection devices on the D+, D- data lines. Data sheets and support documentation can be found on Micrel's web site at www.micrel.com. • ±15kV ESD protection on VBUS, D+ and D• Smaller 2.5mm × 2.5mm MLF® package • USB 1.1 and 2.0 compliant transceiver (full speed 12Mbs and low speed - 1.5Mbps) operation • Separate I/O supply with operation down to 1.6V • Integrated speed select termination supply • Very-low power consumption to meet USB suspend current requirements • No power supply sequencing requirements • Software controlled enumeration Applications • • • • PDAs Palmtops Cell phones PC peripherals Ordering Information Part Number Junction Temp. Range Package - Pb Free -40°C to +85°C 2.5mm×2.5mm MLF® MIC2551AYML25 Typical Application MIC2551A Transceiver V I/O USB Controller GND VIF CON OE# RCV VP VM SPD SUS VTRM VPU VBUS D+ D– 1.0µF 1.5 k VBUS 20Ω 1% 20Ω 1% 10µF D+ D– GND USB Port GND Typical Application Circuit MicroLeadFrame and MLF are registered trademarks of Amkor Technology. Micrel, Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel + 1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com March 2010 1 M9999-030810 MIC2551A-2.5 Micrel, Inc. Pin Configuration SPD VIF VBUS 14 13 12 RCV 1 11 VPU VP 2 10 VTRM VM 3 9 D+ CON 4 8 D- 5 6 7 GND SUS OE# 14-Pin MLF® (ML) Pin Description Pin Number Pin Name I/O Pin Description 1 RCV O Receive Data: Output for USB differential data. 2 VP I/O If OE# = 1, VP = Receive output (+) If OE# = 0, VP = Driver input (+). 3 VM I/O If OE# = 1, VM = Receive output (-) If OE# = 0, VM = Driver input (-). 4 CON I 5 GND 6 SUS I Suspend: Active-High. Turns off internal circuits to reduce supply current. 7 OE# I Output Enable: Active-Low. Enables the transceiver to transmit data onto the bus. When inactive, the trasceiver is in the receive mode. 8 D- 9 D+ 10 CONNECT (Input): Controls state of VPU. Refer to VPU pin description for detail. Ground Reference. I/O Differential data lines conforming to the USB standard. VTRM O 3.3V Reference Supply Output: Requires a minimum 0.1µF decoupling capacitor for stability. A 1µF capacitor is recommended. 11 VPU O Pull-up Supply Voltage Output: Used to connect 1.5kΩ pull-up speed detect resistor. If CON = 1, VPU is high impedance. If CON = 0, VPU = 3.3V. 12 VBUS I USB Bus Supply Voltage: Used to power USB transceiver and internal circuitry. 13 VIF I System Interface Supply Voltage: Used to provide reference supply voltage for system I/O interface signaling. 14 SPD I Edge Rate Control: A logic HIGH operates at edge rates for "full speed" operation. A logic LOW operates edge rates for "low-speed" operation. M9999-030810 2 March 2010 MIC2551A-2.5 Micrel, Inc. SUS OE# D+, D– RCV VP/VM Function 0 0 Driving Active Active Normal transmit mode. 0 1 Receiving Active Active Normal receive mode. 1 0 Hi-Z 0 Not Active 1 1 Hi-Z 0 Active Low power state. Receiving during suspend (low power state) (Note 1) Note 1. During suspend, VP and VM are active in order to detect out-of-band signaling conditions. Table 1. Function Selection OE# = 0: Input Output Result VP VM D+ D– RCV 0 0 0 0 X SE0 0 1 0 1 0 Logic 0 1 0 1 0 1 Logic 1 1 1 1 1 X Undefined D+ D– VP VM RCV 0 0 0 0 X SE0 0 1 0 1 0 Logic 0 1 0 1 0 1 Logic 1 1 1 1 1 X Undefined OE# = 1: Input Output Result X - Undefined Table 2. Truth Table During Normal Mode March 2010 3 M9999-030810 MIC2551A-2.5 Micrel, Inc. Absolute Maximum Ratings (Note 1) Operating Ratings (Note 2) Supply Voltage (VBUS)................................................... 6.5V All Other Inputs................................................–0.5V to 5.5V Ambient Storage Temperature................... –65°C to +150°C Output Current (D+, D–)........................................... ± 50mA Output Current (all others)......................................... ±15mA Input Current............................................................. ±50mA ESD, Note 3 VBUS, D+, D–..........................................................±15KV All other pins.............................................................±2KV Supply Voltage (VBUS)....................................4.0V to 5.25V Ambient Operating Temperature................. –40°C to +85°C Package Thermal Resistance MLF® (θJA)..........................................................59(°C/W) DC Electrical Characteristics (System and USB Interface) (Note 6) VIF = 3.6V, VBUS = 5V unless otherwise noted; TA = 25°C. Bold indicates specifications over temperature, -40°C to 85°C. Symbol Parameter Conditions VBUS USB Supply Voltage VIF System I/F Supply Voltage VIL LOW-Level Input Voltage, Note 4 VIH HIGH-Level Input Voltage, Note 4 VOH HIGH-Level Output Voltage, Note 4 IOH = 20µA VOL LOW-Level Output Voltage, Note 4 IOL = 20µA IIL Input Leakage Current, Note 4 Symbol Parameter IIF IVBUS VIF Supply Current VBUS Supply Current Min Typ Max Units 4.0 5.25 V 1.6 3.6 V VIF-0.3 0.15VIF V 0.85VIF VIF+0.3 V 0.9VIF V 0.1 -5 5 µA Typ Max Units 1 5 µA f = 6MHz CLOAD = 50pF, Note 6 325 650 µA f = 750MHz CLOAD = 600pF, Note 6 40 75 µA Conditions OE# Voltage V Min SPD SUS 1 0 1 1 0 0 0 0 1 0 0 0 0 1 0 1 0 0 0 0 0 1 0 1 800 1100 µA 1 0 0 3000 5000 µA 0 0 1 230 350 µA 0 0 0 400 700 µA 0 1 0 130 200 µA 1 0 0 f = 6MHz CLOAD = 50pF, Note 6 7.3 10 mA 0 0 0 f = 750MHz CLOAD = 600pF, Note 6 3.6 5 mA Typ Max Units VBUS = 5.25V VIF = 3.6V VBUS = 5.25V VIF = 3.6V Symbol Parameter Conditions Load Min IVPULEAK VPU Leakage Current CON = 1, VPU = 0V -5 5 µA IVIFLEAK VIF Leakage Current VIF = 3.6V, VBUS = 0V -5 5 µA VPU Pull-Up Output Voltage ITERM = 200µA, VBUS = 4.0 to 5.25V 3.0 3.6 V RSW Internal Pull-Up Termination ITERM = 10mA, VBUS = 4.0 to 5.25V M9999-030810 4 3.3 10 Ω March 2010 MIC2551A-2.5 Symbol Parameter Micrel, Inc. Conditions Min Typ Max Units ESD Protection IEC-1000-4-2 Air Discharge (D+, D-, VBUS Contact Discharge only) 10 pulses ±15 kV 10 pulses ±15 kV DC Electrical Characteristics (Transceiver) (Note 6) Leakage Current ILO Hi-Z State Data Line Leakage (Suspend Mode) 0V < VIN < 3.3V, SUS = 1 -10 10 µA Input Levels VDI Differential Input Sensitivity |(D+) - (D-)| 0.2 VCM Differential Common Mode Range Includes VDI range 0.8 VSE Single-Ended Receiver Threshold V 2.5 0.8 Receiver Hysteresis 2.0 200 V V mV Output Levels VOL Static Output Low RL = 1.5kΩ to 3.6V VOH Static Output High RL = 1.5kΩ to GND CIN Transceiver Capacitance Pin to GND ZRDV Driver Output Resistance Steady-state drive 2.8 0.3 V 3.6 V Capacitance 10 8 16 pF 24 Ω AC Electrical Characteristics (Notes 5) Driver Characteristics (Low Speed) TR Transition Rise Time CL = 50pF, Figure 2 CL = 600pF 75 TF Transition Fall Time CL = 50pF, Figure 2 CL = 600pF 75 TR, TF Rise/Fall Time Matching (TR, TF) VCRS Output Signal Crossover Voltage 300 300 ns ns 80 125 % 1.3 2.0 V Driver Characteristics (Full Speed) TR Transition Rise Time CL = 50pF, Figure 2 4 20 ns TF Transition Fall Time CL = 50pF, Figure 2 4 20 ns TR, TF Rise/Fall Time Matching (TR, TF) 90 111.11 % VCRS Output Signal Crossover Voltage 1.3 2.0 V Transceiver Timing tPVZ OE# to RCVR Tri-State Delay Figure 1 tPZD Receiver Tri-State to Transmit Delay Figure 1 15 tPDZ OE# to DRVR Tri-State Delay Figure 1 tPZV Driver Tri-State to Receiver Delay Figure 1 tPLH tPHL VP, VM to D+, D- Propagation Delay Figure 4 15 ns tPLH tPHL D+, D- to RCV Propagation Delay Figure 3 15 ns tPLH tPHL D+, D- to VP, VM Propagation Delay Figure 3 8 ns 15 ns ns 15 15 ns ns 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. Specification applies to the following pins: SUS, SPD, CON, RCV, VP, VM, OE#. Note 5. All AC parameters guaranteed by design but not production tested. Note 6. Specification for packaged product only. March 2010 5 M9999-030810 MIC2551A-2.5 Micrel, Inc. Timing Diagrams RECEIVE TRANSMIT OE# tPVZ tPZV VP/VM tPDZ tPZD D+/D– Figure 1. Enable and Disable Times Rise Time Differential Data Lines Fall Time 90% 90% 10% 10% tR tF Figure 2. Rise and Fall Times D+ VCRS D– Differential Data Lines VCRS tPHL tPLH VOH VOL VSS Figure 3. Receiver Propagation Delay VOH VOL D+ tPHL tPLH VCRS D– Differential Data Lines VCRS Figure 4. Driver Propagation Delay Test Circuits D.U.T. 25pF Figure 5. Load for VP, VM, RCV VTRM 1.5k D.U.T. 20 15k CL Figure 6. Load for D+, D– M9999-030810 6 March 2010 MIC2551A-2.5 Micrel, Inc. Functional Diagram To Internal Circuitry LDO Regulator VIF VBUS VTERM VPU CON D+ SPD OE# D– Level Translator RCV VP VM SUS GND MIC2551A Applications Information The MIC2551A is designed to provide USB connectivity in mobile systems where available system supply voltages are not able to satisfy USB requirements. The MIC2551A can operate interface supply voltages as low as 1.6V and still meet the USB physical layer specifications. As shown in the circuit above, the MIC2551A takes advantage of the USB supply voltage, VBUS, to operate the transceiver. The system voltage, VIF, is used to set the reference voltage used by the digital I/O lines interfacing to the system controller. Internal circuitry provides translation between the USB and system voltage domains. VIF will typically be the main supply voltage rail for the controller. March 2010 In addition, a 3.3V, 10% termination supply voltage, (VPU), is provided to support speed selection. VPU can be disabled or enabled under software control via the CON input. This allows for software-controlled connect or disconnect states. A 1.5k resistor is required to be connected between this pin and the D+ or D– lines to respectively specify high speed or low speed operation. 7 M9999-030810 MIC2551A-2.5 Micrel, Inc. Power Supply Configuration The MIC2551A can be set up for different power supply configurations which modify the behavior of the device. Both VBUS and VIF have special thresholds that detect when they are either removed or grounded. Table 1 depicts the behavior under the different power supply configuration scenarios that are explained below. Speed The speed pin (SPD) sets D+/D– output edge rates by increasing or decreasing biasing current sources within the output drivers. For low speed, SPD = 0. For full speed, SPD = 1. By setting SPD = 0 during idle periods, in conjunction with suspend (SUS), the lowest quiescent current can be obtained. However, designers must provide a 300ns delay between changing SPD from 0 to 1 and transmission of data at full speed. This delay ensures the output drivers have arrived at their proper operating conditions. Failure to do so can result in leading edge distortion on the first few data bits transmitted. Non-Multiplexed Bus In order to save pin count for the USB logic controller interface, the MIC2551A was designed with VP and VM as bi-directional pins. To interface the MIC2551A with a non-multiplexed data bus, resistors can be used for low cost isolation, as shown in Figure 8. Normal Mode VBUS is connected to the 5.0V USB bus voltage and VIF is connected to a supply voltage in the range of 1.6V to 3.6V. In this case VTRM supplies a 3.3V voltage for powering the speed select resistor via VPU depending on the state of CON pin. Disconnect Mode VIF is connected to a supply in a range of 1.6V to 3.6V and VBUS is open or grounded. If VBUS is opened while transmitting, the data lines (D+, D–) have sharing capability and may be driven with external devices up to approximately 3.6V if and only if SUSPEND is enabled (SUS = 1). With VBUS ground, D+, D– sharing mode is not permitted. USB Logic Controller (SIE) Disable Mode VP VBUS is connected to the 5.0V USB bus voltage and VIF is open. All logic controlled inputs become high impedances, thus minimal current will be supplied by VIF if the input pins are pulled up to an external source. Alternate Power Supply Configuration Option MIC2551A 10k VP VPO VM 10k VM VMO I/O Interface Using 3.3V Figure 8. MIC2551A Interface to Non-Multiplexed Data Bus In systems where the I/O interface utilizes a 3.3V USB controller, an alternate solution is shown in Figure 7. No extra components are required; however, the load on VTRM must not exceed 10mA. 3.3V MIC2551A VDD USB Controller VIF I/O VBUS VBUS VTRM VP/VM/ RCV/OE# Figure 7. I/O Interface Using 3.3V Signal Amplitude Respective to VIF When operating the MIC2551A, it is necessary to provide input signals which do not exceed VIF + 0.3V. Suspend When the suspend pin (SUS) is high, power consumption is reduced to a minimum. VTRM is not disabled. RCV, VP and VM are still functional to enable the device to detect USB activity. For minimal current consumption in suspend mode, it is recommended that OE# = 1, and SPD = 0. M9999-030810 8 March 2010 MIC2551A-2.5 Configuration Mode Normal Disconnect (D+/Dsharing) Disconnect Disable Mode Unpowered Micrel, Inc. VBUS/VTRM VIF Notes Connected Connected Normal supply configuration and operation. Open Connected VP/VM are HIGH outputs, RCV is LOW. With OE# = 0 and SUS = 1, data lines may be driven with external devices up to 3.6V. With D+, D- floating, IIF draws less than 1µA. Ground Connected VP/VM are HIGH outputs, RCV is LOW. With D+, D- floating, IIF draws less than 1µA. Connected Open Connected Ground Logic controlled input pins are Hi-Z. No communication is possible until interface voltage is restored. Inoperative Table 1. Power Supply Configuration PCB Layout Recommendations Although the USB standard and applications are not based in an impedance-controlled environment, a properly designed PCB layout is recommended for optimal transceiver performance. The suggested PCB layout hints are as follows: • Match signal line traces (VP/VM, D+, D–) to 40ps, approximately one-third inch if possible. FR-4 PCB material propagation is about 150ps/ inch, so to minimize skew try to keep VP/VM, D+/D– traces as short as possible. • For every signal line trace width (w), separate the signal lines by 1.5 – 2 widths. Place all other traces at >2 widths from all signal line traces. • Maintain the same number of vias on each differential trace, keeping traces approximately at same separation distance along the line. • Control signal line impedances to ±10%. • Keep RS as close to the IC as possible, with equal distance between RS and the IC for both D+ and D–. March 2010 9 M9999-030810 MIC2551A-2.5 Micrel, Inc. Package Information 14-Pin MLF® (ML) MICREL INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA tel + 1 (408) 944-0800 fax + 1 (408) 474-1000 web http://www.micrel.com This information furnished by Micrel in this data sheet is believed to be accurate and reliable. However no responsibility is assumed by Micrel for its use. Micrel reserves the right to change circuitry and specifications at any time without notification to the customer. Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A Purchaser's use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser's own risk and Purchaser agrees to fully indemnify Micrel for any damages resulting from such use or sale. © 2005 Micrel Incorporated M9999-030810 10 March 2010