8

Figure 8. Schematic Diagram for USB, PS/2 mouse application with ADNS-3080

Notes

•

Caps for pins 15 and 17 MUST have trace lengths LESS than 5 mm to nearest ground pin.

•

Pins 15 and 17 caps MUST use pin 16 GND.

•

Pin 9, if used, should not be connected to PCB GND to reduce potential RF emissions.

•

The 0.1 uF caps must be ceramic.

•

Caps should have less than 5 nH of self inductance.

•

Caps should have less than 0.2 Ω ESR.

•

NC pins should not be connected to any traces.

•

Surface mount parts are recommended.

•

Care must be taken when interfacing a 5V microcontroller to the ADNS-3080. Serial port inputs on the sensor should be connected to open-

drain outputs from the microcontroller or use an active drive level shifter. NPD and RESET should be connected to 5V microcontroller outputs

through a resistor divider or other level shifting technique.

•

VDD3 and GND should have low impedance connections to the power supply.

•

Capacitors connected to pin 15 and 17 should be connected to pin 16 and then to pin 19.

0.1

uF

14

10

Vcc

Vpp

9

VSS

Ceramic Resonator

Murata

CSALS 24 M 0X 53 -B 0

TDK FCR 24. 0 M 2G

17

5

V DD

LED_CTRL

SURFACE

Internal

Image

Sensor

ADNS

2120

Lens

HLMP-ED80

24 MHz

8

10

OSC_OUT

OSC_IN

15

GND

24

P0.5*

3

P0.4*

4

6

MOSI

RESET

P0.2

23

1.3 K

Ω

16

15

D -

D +

Vreg

11

P1.7

P1.5

P1.4

17

18

7

Vcc

D +

D -

GND

SHLD

6 MHz

12

13

XTALIN

XTALOUT

(Optional)

6

5

P1.2

P1.0

Buttons

L

M

V DD

19

16 GND

REFB

14

P0.3

7

NPD

4

P0.7*

3

SCLK

21

P0.6

2

MISO

22

9

GUARD

11 18

20

P1.1

R

20K

Ω

20K

Ω

1

NCS

LP2950ACZ-3.3

13

REFC

2.2

uF

187

Ω

1/8 W

Vcc

Vo 3.3V

12

OPTP

20

10 K

Ω

10 K

Ω

Vcc

Vcc

QA

QB

ALPS

EC10E

Scroll Wheel

Encoder

1

2

3

20k

Ω

20k

Ω

0.1uF

4.7uF

0.1uF

Vin

Vo

GND

2

4.7uF

+

0.1uF

3

1

BS170

+

+

Notes:

- All capacitors close to chip

- 24MHz and 6MHz oscillators close to chip

- * Outputs configured as open drain