MAX4999 USB 2.0 Hi-Speed Differential 8:1 Multiplexer
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USB 2.0 Hi-Speed Differential 8:1 Multiplexer General Description The MAX4999 differential Hi-Speed USB analog multiplexer features low on-capacitance (CON) switching, making it an ideal solution for the USB server/mass storage market. The MAX4999 is designed for USB 2.0 low-/full-/Hi-Speed applications with capability of supporting data rates up to 480Mbps. The MAX4999 is a differential 8:1 multiplexer. The MAX4999 features three digital inputs to control the signal path. Typical applications include switching a USB connector between eight USB hosts and a USB device. An enable input (EN) is provided to disable all channels and place the device into a high-impedance state (standby mode), shutting off the charge pump for minimum power consumption. • Increased Flexibility and Performance • Multiplexer Supports USB 2.0 Standard • -3dB Bandwidth: 1200MHz (typ) The MAX4999 operates from a +3.0V to +3.6V powersupply voltage and is specified over the -40°C to +85°C extended temperature range. The MAX4999 is available in a 5mm x 5mm, 32-pin TQFN package. Applications Keyboard, Video, Mouse (KVM) Servers/RAID Mass Storage Workstations • Low On-Resistance and Power Management Features Minimize System Losses • 6.5Ω (typ) On-Resistance (RON) • Single +3.0V to +3.6V Power-Supply Voltage • Enable Input Puts All Channels in High-Impedance State (Standby Mode) • Low Operating Current (1µA) and Ultra-Low Quiescent Current (30nA) in Standby Mode • Reduce Component Count and Design Complexity • Low Threshold Eliminates the Need for Translators in 1.8V Low-Voltage Systems • Saves Board Space • 32-Pin, 5mm x 5mm, TQFN Package Ordering Information PART TEMP RANGE +Denotes a lead(Pb)-free/RoHS-compliant package. *EP = Exposed pad. TQFN 5mm x 5mm *CONNECT EXPOSED PAD TO GND.

USB 2.0 Hi-Speed Differential 8:1 Multiplexer Note 1: Signals exceeding GND are clamped by internal diodes. Limit forward-diode current to maximum current rating. 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 (VCC = +3.0V...

USB 2.0 Hi-Speed Differential 8:1 Multiplexer Electrical Characteristics (continued) (VCC = +3.0V to +3.6V, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VCC = +3.3V and TA = +25°C.) (Note 3) PARAMETER Turn-Off Time Output Skew Same Port Skew between any D_ _0, D_ _1 line, same port 45Ω unbalanced I/O, f = 240MHz (Figure 2) Input Logic High SWITCH LOGIC Input Logic Hysteresis Input Leakage Current Human Body Model Note 3: All units are 100% production tested at TA = +85°C. Limits over the operating temperature range are guaranteed by design and not production tested....

Electrical Characteristicsest Circuits/Timing Diagrams (continued) -0UT+ RISE-TIME PROPAGATION DELAY = tPLH. FALL-TIME PROPAGATION DELAY = tpHL Figure 2. Propagation Delay and Skew

USB 2.0 Hi-Speed Differential 8:1 Multiplexer Electrical CharacteristicsTest Circuits/Timing Diagrams (continued) VCC 0.1μF VOUT VIN VOUT VIN VOUT VIN MEASUREMENTS ARE STANDARDIZED AGAINST SHORT AT SOCKET TERMINALS. OFF-ISOLATION IS MEASURED BETWEEN COM_ AND "OFF" USB_ TERMINAL ON EACH SWITCH. ON-LOSS IS MEASURED BETWEEN COM_ AND "ON" USB_ TERMINAL ON EACH SWITCH. CROSSTALK IS MEASURED FROM ONE USB_ CHANNEL TO ANOTHER USB_ CHANNEL. SIGNAL DIRECTION THROUGH SWITCH IS REVERSED; WORST VALUES ARE RECORDED. Figure 3. Off-Isolation, On-Loss, and Crosstalk

USB 2.0 Hi-Speed Differential 8:1 Multiplexer Typical Operating Characteristics (VCC = +3.3V, TA = +25°C, unless otherwise noted.) LOGIC THRESHOLD vs. SUPPLY VOLTAGE FREQUENCY RESPONSE QUIESCENT SUPPLY CURRENT vs. TEMPERATURE QUIESCENT SUPPLY CURRENT (µA) LEAKAGE CURRENT vs. TEMPERATURE

USB 2.0 Hi-Speed Differential 8:1 Multiplexer Power-Supply Input. Bypass VCC to GND with a 0.1µF capacitor placed as close to VCC as possible. Enable Input Control Input 0 Control Input 1 Analog Switch 0 D- Terminal Analog Switch 0 D+ Terminal Analog Switch 1 D- Terminal Analog Switch 1 D+ Terminal Analog Switch 2 D- Terminal Analog Switch 2 D+ Terminal Analog Switch 3 D- Terminal Analog Switch 3 D+ Terminal Analog Switch 4 D+ Terminal Analog Switch 4 D- Terminal Analog Switch 5 D+ Terminal Analog Switch 5 D- Terminal Analog Switch 6 D+ Terminal Analog Switch 6 D- Terminal Analog Switch 7...

USB 2.0 Hi-Speed Differential 8:1 Multiplexer Functional Diagram/Truth Table Applications Information Increasing USB Channels The MAX4999 features an enable input that allows two MAX4999s to be connected, allowing multiplexing between 16 USB channels. Figure 4 shows the typical application with a single USB common terminal multiplexed to eight channels (8:1). See the Eye Diagram Single graph in the Typical Operating Characteristics. Figure 5 shows two MAX4999 devices configured with the USB common terminal multiplexed to 16 USB channels (16:1). See the Eye Diagram - Double graph in the...

USB 2.0 Hi-Speed Differential 8:1 Multiplexer Figure 4. The MAX4999 Multiplexes Between Eight Differential Channels (8:1) USB D+, D- MUST BE REVERSED IF DEVICES ARE CONNECTED AS SHOWN, THIS IS TRUE OF D0_ _ TO D7_ _. C0, C1, C2 ARE CONNECTED IN PARALLEL. EN0 AND EN1 ARE USED TO SELECT BETWEEN DEVICE 0 AND DEVICE 1. Figure 5. Combining Two MAX4999 Devices for 16:1 USB Connections

USB 2.0 Hi-Speed Differential 8:1 Multiplexer Chip Information Package Information PROCESS: CMOS For the latest package outline information and land patterns (footprints), go to www.maximintegrated.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. PACKAGE TYPE