adns-5700 Avago Technologies, adns-5700 Datasheet - Page 2

• Manufacturer Part Number: adns-5700
• Description: Pcb Design Guidelines For Adns-5700 One Chip Usb Led Sensor
• Manufacturer: Avago Technologies

PCB Layout Design and Assembly Recommendations
1. Grounding
2. VDD5
2
A good grounding layout can enhance the EMI, EFT
and ESD performance.
• MUST have a continuous ground plane and unbroken
• MUST NOT use jumper to connect the GND planes.
• Connect USB-GND and USB-Shield planes as a single
• All decoupling capacitors as shown in the application
VDD5 is the 5volts power supply from USB bus to
ADNS-5700 sensor. This VDD5 power line can be layout
as a small plane or a single line with the recommended
value of decoupling capacitors to DGND. The power
line path should be as short as possible and jumper can
be used if necessary. See Figure 5.
plane from USB connector to sensor ground pins 8
and 13. The plane should be as short and thick as
possible.
GND plane should be the largest piece in the
layout.
plane. The sensor grounding pins 9 and 13 are to be
connected to USB-GND directly.
schematic should be connected to their respective
GND plane.
Figure 2. Grounding Layout
GND
GND
3. D+ and D–
• D+ and D– are the USB data lines. Both data lines must
• The D+ and D– MUST be filtered with 33ohm and
be layout in same length with the shortest possible
path and placed as far away from the resonator or
high frequency traces. In addition, avoid using any
jumpers on these data lines. Good layout practice
on data lines can improve on EMI performance. In
addition the parallel D+/– traces can be contained
by ground plane to reduce coupling effects from
high frequency traces.
100pF circuit.
D+/ traces
contained
by GND
Figure 3. Grounding Layout
Figure 4. D+/– circuit
G
N
D
G
N
D