– 6 –

CXA2610AN

Notes on Operation

• Locate the external resistors connected to the IINR, IIN2 and IIN3 pins close to the IC package to prevent the

effect from other signal lines.

• Make the wiring distance between the output LD0 pin and the laser diode as short as possible.

If this wiring is longer, the output waveform characteristics show that the rise and fall times (Tr and Tf)

become slower as the ringing becomes larger.

• The external resistor connected to Pin 10 (OSCGA) should be within the range from 12

Ω to 2kΩ.

In addition, this resistance value should be set in consideration of the laser diode Ith so that the oscillation

level at IINR = 0V does not exceed the read power.

• Temperature assurance

The junction temperature for the CXA2610AN laser driver should not exceed 150°C. In addition, the power

lowered thermal resistance (

θj-a) for board mounting so that normal operation is possible at the maximum

operating temperature of 70°C.

Widening the GND area on the set board and other heat radiation countermeasures within the set are

necessary in order to lower

θj-a.

This is because the CXA2610AN thermal resistance (

θj-a) differs according to the board, and the power

Obtain the thermal resistance (

or, the power consumption can also be obtained as follows.

Thermal resistance (

θj-a) when mounted on a board

The diode temperature coefficient is –2.27mV/°C

thermally balanced state = V3

The change in current consumption between (1) and (2)

This

(

reference.

The voltage fall coefficient (VR) used to correct this

Using VR to apply correction to V3 yields the equation:

(

From this,

θj-a

• Maximum operating temperature 70 °C

(150°C –

∆Tj) ≥ 70°C

Thus, if

θj-a can be lowered from these two conditions, the maximum operating temperature can also

be raised.

10

11

5V

5V

5V

10V

1M

Ω

Diode measurement point

ENABLE

9

Thermal Resistance Measurement Circuit