PixArt Imaging Inc.
PAW3504
Pure USB Optical Mouse Sensor Single Chip
6. Referencing Application Circuit
Y1 24Mhz
VDD_5V_10R
U1
ENSW1
VDD_5V
*R3 OPEN
BL
1
2
3
4
5
6
14
13
12
11
10
9
OSCIN
BL
OSCOUT
Z1
Z1
VDD_5V
R1
COM
Z2
+C2
10uF
JP1
C5
0.1uF
D1
LED
*R2 OPEN
LED
Z2
VBUS
GND
Shield
D-
BM
BR
VDDQ
VSS
BM
BR
C4 1uF
VDD_5V_10R
R6 10 ohm
VDD_5V
R4
R5
33 ohm
33 ohm
VDD5V
VDDA
D-
7
8
D+
D+
C1
C3
C6
C7
27pF
USB CABLE
+
PAW3504
0.1uF 1uF
27pF
Note:
1. *R2 is left for PAN3401 with PS/2 interface
2. *R3 is left for PAN3502 RC Oscillator
3. R4,R5,C6,C7 are for EMCimmunity
4. USB cable connector JP1 is suggested to has the pin sequence like this:
VBUS, GND, Shield, D-, D+
Figure 7. Application Circuit for PAW3504
6.2 PCB Layout Guideline
The following guidelines apply to component placement and routing on the PCB. That will get an optimum
EMC solution and tracking performance.
6.2.1 Key Components Placement Rules
1. Place resonator (Y1) near SENSOR pin1 and pin 14.
2. Place bulk capacitor (C2) and bypass (C5) near the USB CABLE.
3. Place C1 and C3 near SENSOR pin 6 and pin 7.
4. The C6/C7 and R4/R5 should be placed as close to the USB CABLE.
6.2.2 Routing Rules
1. Caps for pins 4, 6, 7 trace length must be less than 5 mm.
2. The trace length of OSCOUT, OSCIN must be less than 10 mm.
3. Other general rules refer file”PAW3504DLY PCB Layout Guide”
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10
V1.0 June. 2008
PixArt Imaging Inc.
E-mail: fae_service@pixart.com.tw
PIXART [ PIXART IMAGING INC. ]
