TUSB6015ZQE

SLLS937

REVISION 1.4 SEPTEMBER 12, 2008

External Components

USB PHY Voltage and Current Bias Resistor Pin: R1

This signal must connect to a precision external resistance to set the internal operating reference currents and

cable driver output currents. A resistance of 10.7 k• ± 1% (temperature coefficient ±100ppm/°C) is necessary to

meet requirements set forth in the Universal Serial Bus Revision 2.0 specification.

The side of the resistor not connected to the R1 signal should connect through a low impedance path to the circuit

board ground plane.

USB PHY Voltage and Current Reference Ground: VSSREF

This signal is the reference ground for the voltage and current reference circuitry internal to the Data/Port macro.

This signal must connect to the low impedance circuit board ground plane.

USB PHY Power Connections: VDDCM1P5, VDDA1P5, VDDD1P5, VDDA3P3

Decoupling capacitors are required to suppress high-frequency switching noise and stabilize the supply voltage. A

decoupling capacitor is most effective when it is close to the chip. This minimizes the inductance of the circuit

board wiring and interconnects.

The USB 2.0 PHY Macro has two power rails, 1.5V (VDDCM1P5, VDDD1P5, VDDA1P5) and 3.3V (VDDA3P3).

Each power connection has its own associated ground connection, 1.5V (VSSCM1P5, VSSD1P5, VSSA1P5) and

3.3V (VSSA3P3). Each supply is isolated from the others to provide noise isolation.

A combination of high-frequency capacitors near each terminal is suggested, such as paralleled 1uF, 0.01uF, and

0.001uF capacitors. A lower frequency 10uF filter capacitor is also recommended. A series inductor on the

analog supplies is also recommended. All ground pins must connect through a low impedance path to the circuit

board ground plane. All grounds can be connected to each other.

• VDDCM1P5 (Common Module 1.5V Supply) - (1) 1µf , (1) 0.1µf, 0.01µf, (1) 0.001µf, (1) 10µf

• VSSCM1P5 (Common Module Ground)

• VDDD1P5 (Digital 1.5V Supply) - (1) 0.1µf, (1) 0.001µf, (1) 10µf

• VSSD1P5 (Digital 1.5V Ground)

main supply and the device, the caps between the inductor and the device.

• VSSA1P5 (Analog 1.5V Ground)

• VDDA3P3 (Analog 3.3V Supply) - (1) 0.1µf, (1) 0.001µf, (1) 10µf, with a series inductor between the

main supply and the device, the caps between the inductor and the device.

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