PAW3702DL-TXNT Datasheet, PDF (15/33 Pages) Pixart Imaging Inc. – 3in1 SOC Low Power 2.4GHz Wireless Optical Mouse

PixArt Imaging Inc.
PAR2402QK-RB General Datasheet
2.4GHz Wireless Receiver for USB Dongle
5.0 Design References
5.1 Reference Schematics
The circuit design of PAR2402 is easy as the EBOM is very simple.
16MHz crystal (CL=12pF)
Y1
C3 C4
0.1uF 0.1uF
JP1
U1
USB
C9
4.7uF
R3 4.3R
C10 0.1uF
VDD3V3
C13 0.1uF
VDD3V3
D+
D-
1
VDD_OUT
2
VDD_USB
3
VDD_DIG
4
USB_D+
PAR2402
5
USB_D-
QFN32-5X5
6
NC
7
VPP_OTP (RESETB)
8
NC
24
NC
23
NC
22
ANT
21
NC
20
NC
19
VDD_MTP
18
NC
17
PROG
L2
NC
C1
ANTENNA1
1
0R
Antenna
C1,L2 reserve for
antenna matcing
VDD3V3
Figure 8. PAR2402 Reference Application Circuit
5.2 Design Guidelines
5.2.1 Layout Design
Taking precaution in printed circuit layout is critical in optimizing the design to minimize parasitical capacitance and line
inductance. The following layout guidelines are recommended to achieve optimum performance.
1. Ensure that the RF 50ohm trace comes with GND continuation.
2. Place the ceramic bypass capacitors as near as possible to the input/output pins.
3. All feedback signals must first go through regulator capacitors.
4. Place the crystal closely to the oscillator pins.
5. Ensure that the ground plane under the oscillator and its components are of good quality.
6. Do not route any digital-signal lines on the other side of the PCB that under the RF trace and crystal area.
7. Keep other digital signal lines, especially clock lines and frequently switching signal lines, as far away from
crystal/analog/RF connections as possible.
8. Place at least 9 GND vias directly under IC thermal PAD for good grounding and thermal dissipation.
Version 0.6 | 17 June 2016 | A1003AEN
PixArt Imaging Inc. http://www.pixart.com
All rights reserved. Any portion in this paper shall not be reproduced, copied, or transformed to any other forms without permission.
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