NJW4710

- 1 -

Ver.1

4ch Laser Diode Driver for Blue Laser Diode

GENERAL DESCRIPTION

PACKAGE OUTLINE

NJW4710 is a laser diode driver for the operation of a grounded

blue laser diode. It is suited to drive a blue laser diode, because it is
operated by split power supply. It includes 4 channels current amplifiers
for 4 different optical power levels. An on-chip RF oscillator is provided
to reduce laser mode noise during read mode. Oscillation frequency
and oscillation amplitude are defined by two external resistors

FEATURE

Operating Voltage Vcc1=4.5V to 5.5V, Vcc2=8.0 to 10.0V

Internal Oscillator Circuit 200MHz to 500MHz

Rise Time / Fall Time 0.8ns typ.

Maximum Output Current 250mA typ.

Bi-CMOS Technology

Package Outline SSOP24-E1

PIN CONFIGURATION

BLOCK DIAGRAM

1:GND
2:IinR
3:GND
4:Iin2
5:Rfreq
6:Iin3
7:Iin4
8:Vcc1
9:OUTEN2
10:OUTEN3
11:OUTEN4
12:GND

13:GND
14:Vcc2
15:Vcc2
16:OSCEN
17:ENABLE
18:Ramp
19:GND
20:Iout
21:Iout
22:Vcc2
23:Vcc2
24:GND

Vcc1

INR

GND

Iout

OSCEN

ENABLE

BIAS

Ramp

OSC

Rfreq

OUTEN2

OUTEN3

OUTEN4

Vcc2

IN2

IN3

IN4

CH-R

CH-2

CH-3

CH-4

NJW4710VE1

NJW4710

- 2 -

Ver.1

ABSOLUTE MAXIMUM RATINGS(Ta=25

PARAMETER SYMBOL

RATINGS UNIT

Supply Voltage 1

Vcc1

6.0

Supply Voltage 2

Vcc2

11.0

Input Voltage

Vin

6.0

Power Dissipation

700

Operating Temperature Range

Topr

-40 to +85

Storage Temperature Range

Tstg

-40 to +150

RECOMMENDED OPEARATING CONDITION(Ta=25

PARAMETER SYMBOL

TEST

CONDITION

MIN.

TYP.

MAX.

UNIT

Operating

Voltage1

Vopr1

4.5 5.0 5.5 V

Operating Voltage2

Vopr2

8.0

9.0

10.0

ELECTRICAL CHARACTERISTICS

DC CHARACTERISTICS(Vcc1=5V,Vcc2=9V,ENABLE=H,OUTEN=H,OSCEN=L H:5V,L:GND, Ta=25

PARAMETER SYMBOL

TEST

CONDITION

MIN.

TYP.

MAX.

UNIT

Supply Current 1

ENABLE

0.5V

- 0 10

Supply Current 2

2 IINR/2/3/4=0uA,Rfeq=OPEN,Ramp=OPEN

19 24 mA

Supply Current 3

OSCEN=H, Rfreq=3.6k

,Ramp=5k

- 33 40

Supply Current 4

4 OUTEN=H,

IIN/2/3/4=500uA

62 76 mA

Supply Current 5

5 OUTEN=H,

IINR/2/3/4=500uA

- 120 140 mA

High Level Input Voltage

VIH

OUTEN, OSCEN

Low Level Input Voltage

VIL

OUTEN, OSCEN

1.3

ENABLE High Level
Input Voltage

EVIH ENABLE

ENABLE Low Level
Input Voltage

EVIL ENABLE

1.5 V

OUTEN High Level
Input Current

DIIH OUTEN=5V

10 uA

OUTEN Low Level
Input Current

DIIL OUTEN=0V

-300 -

0 uA

ENABLE High Level
Input Current

EIIH ENABLE=5V

- 500 uA

ENABLE Low Level
Input Current

EIIL ENABLE=0V

-10 -

0 uA

OSCEN High Level
Input Current

OIIH OSCEN=5V

- 450

OSCEN Low Level
Input Current

OIIL OSCEN=0V

-10 -

1 Shut-Down Voltage

Vshut

3.40

3.75

NJW4710

- 3 -

Ver.1

Laser Amplifier DC CHARACTERISTICS(Vcc1=5V, Vcc2=9V ENABLE=H,H:5V,L:GND,Ta=25

PARAMETER SYMBOL

TEST

CONDITION

MIN.

TYP.

MAX.

UNIT

Current Gain

CHR/2/3/4, Vo=5V *1

110

140

/mA

Output Offset Current

Ios

CHR/2/3/4, Vo=5V *1

-5

Output Current Linearity

Iiin

CHR/2/3/4, Vo=5V *1

-3

Input Current Range 1

Iin1

CHR

Input Current Range 2

Iin2

CH2/3/4

3.5

Maximum Output Current 1

Iomax1 CHR

100

Maximum Output Current 2

Iomax2 CH2/3/4

100

200

Iout

Series

Resintance

Iout=200mA

- 10 -

Input Resistance 1

Rin1

CHR

1.62

2.5

3.38

Input Resistance 2

Rin2

CH2/3/4

325

500

675

Output OFF Current 1

Ioff1 ENABLE=L

5 MA

Output OFF Current 2

Ioff2

OUTEN=H, Total for All Channels

Output OFF Current 3

Ioff2 OUTEN=L,

=0uA,Total for All Channels

Output Current
Supply Sensitivity 1

Vc1

1=5V

10%, V

2=10V

10%,Iout=40mA

-1 2 4

%/V

Output Current
Supply Sensitivity 2

Vc2

1=5V

10%, V

2=10V

10%,Iout=80mA

-1 2 4

%/V

Output Current
Temperature Sensitivity 1

TC1

Iout=40mA,CHR

only

- 400 -

ppm/

Output Current
Temperature Sensitivity 2

TC2

Iout=80mA,40mARead+40mA,Write

- 400 -

ppm/

*1 The amplifier linearity is calculated using best fit method at three points. The output currents chosen 20 mA,

40mA,and, 60mA.The transfer function for Iout is defined as follows: Iout =(I

+GAIN)+IOS

Laser Amplifier AC CHARACTERISTICS (Vcc1=5V, Vcc2=9V,Iout=40mA DC with 40mA PULSE, Ta=25

PARAMETER SYMBOL

TEST

CONDITION

MIN.

TYP.

MAX.

UNIT

Rise Time

Iout= 40mA(Read)+40mA(10-90%)

0.8

Fall

Time

Tf Iout=

40mA(Read)+40mA(10-90%)

- 0.8 - ns

Over Shoot

Iout ON Time

Ton

OUTEN 50% H

L to Iout 50%

- 1 - ns

Iout OFF Time

Toff

OUTEN 50% H

L to Iout 50%

- 1 - ns

Disable Time

Tdis

ENABLE 50%H

L to Iout 50%

- 20 - ns

Enable Time

Ten

ENABLE 50%L

H to Iout 50%,

- 150 - ns

HFM Disable Time

Tdiso OSCEN H

L to Iout 50%

- 10 - ns

HFM Enable Time

Teno

OSCEN L

H to Iout 50%,

- 10 - ns

Oscillator Frequency

fOSC Rfreq=3.6k

280 350 420

MHz

Oscillator Temperature
Coefficient

TcOSC Rfreq=3.6k

- -300 - ppm/

Output Current Noise

Ino

Iout=40mA,CHR only

0.9

nA/

NJW4710

- 4 -

Ver.1

Iout Control

ENABLE OUTEN2 OUTEN3 OUTEN4

Iout

L/OPEN X

OFF

H/OPEN H/OPEN H/OPEN

Iout=

INR

*120

H L

H/OPEN

H/OPEN Iout=(I

INR

IN2

)*120

H L L

H/OPEN

Iout=(I

INR

IN2

IN3

)*120

H L L L Iout=(I

INR

IN2

IN3

IN4

)*120

Oscillator Control

ENABLE OSCEN OUTEN2 OUTEN3

OUTEN4

OSCILLATOR

L/OPEN X

X X

OFF

H L/OPEN X

X X

OFF

H H X X

Timing Diagram

Ten

Ton Toff

Tdis

Ton Toff

Iout

OUTEN4

OUTEN3

OUTEN2

ENABLE

NJW4710

- 6 -

Ver.1

TERMINAL EXPLANATION

Pin No.

Pin Name

Function

1
3

12
13
19
24

GND GND

2 IinR

Input of constant current output circuit for Read Channel.
Output current value is set up by input current or input voltage.

4 Iin2

Input of constant current output circuit for Erase, Write Channel.
Output current value is setup by input current or input voltage.

5 Rfreq

Set up for oscillator frequency.
Resistance is connected to GND and a setup in optional frequency.

6 Iin3

Input of constant current output circuit for Erase, Write Channel.
Output current value is setup by input current or input voltage.

7 Iin4

Input of constant current output circuit for Erase, Write Channel.
Output current value is setup by input current or input voltage.

Vcc1

Supply voltage for amplifier circuit: Vcc1=5V

9 OUTEN2

Output current control for channel 2
High(<2V) or OPEN: Non-Output
Low(>1.3V): Output

10 OUTEN3

Output current control for channel 3
High(<2V) or OPEN: Non-Output
Low(>1.3V): Output

11 OUTEN4

Output current control for channel 4
High(<2V) or OPEN: Non-Output
Low(>1.3V): Output

14
15
22
23

Vcc2

Supply voltage for output circuit: Vcc2=9V

16 OSCEN

Output control for oscillator.
High(<2V): Oscillation superposition
Low(>1.3V) or OPEN: Non-Output

17 ENABLE

Control for IC.
High(<3V): Output
Low(>1.5V) or OPEN: Non-Output

18 Ranp

Setup for oscillation superposition.
Resistance is connected to GND and a setup in optional oscillation superposition.

20
21

Iout

Output current terminal.
Please connect cathode common type laser or floating type laser to GND.

*Please set up Low voltage not less than GND-0.3V ,and High voltage of each control terminal (ENABLE,
OUTEN 2, 3, and 4, OSCEN) does not exceed Vcc1+0.3V.

NJW4710

- 7 -

Ver.1

Iin

Rex

Rin

Vin

Rex

Rin

Iin

APPLICATION

Set up for operating voltage

Recommended operating voltage of NJW4710 is Vcc=5V,Vcc=9V.
Vcc2=9V is set up in consideration of the forward voltage [VF] (6V max.) of a Blue Laser Diode.
Therefore, in the case of a Red Laser Diode or Blue Laser Diode with low forward voltage, please set up the

power supply voltage of Vcc2 above the following.

Operating voltage of Vcc2 = forward voltage(MAX) of laser diode + 3V

Set up for output current

Current gains of each channels of all are 120mA/mA typ.
Set up of the output current value in current input and voltage input is below.

In the case of current input

Please input current to IC. Output current is the following.

Iout=120*Iin [mA]

In the case of current input

Output current is the following.

Iout=120*Vin/(Rex+Rin) [mA]

Output current can be set up by Rex=0ohm.
However, to reduce input noise,
please add a capacitor between Rex and GND.
(Refer to TEST CIRCUIT).
Rin(input resistance of IC) is CH-R:2.5kohm,CH-2/3/4:500ohm.

Set up for internal Oscillator

NJW4710 contained in the oscillator for the light power change reduction by the return light noise of laser.
The quality of reading improves by operating oscillator and output it.
In this oscillator, oscillation frequency can be set up by connect resistance with a Rfreq(5pin) between GND.
Moreover, set up of the amount of oscillation superposition can be performed by connect resistance with a
Ramp(18pin) between GND.
Oscillation frequency is 150MHz to 600MHz. It can adjust to 10mApp to 100mApp (Refer to TYPCAL
CHARACTERISTICS) in the amount of high frequency superposition.
Output of this oscillator is PUSH-PULL circuit. Therefore, the output of the oscillator for high frequency
superposition is overlapped focusing on the output current value set up in the constant current output circuit.

Fig.2 In the case of current input

Fig.3 In the case of voltage input

NJW4710

- 8 -

Ver.1

100

200

300

400

500

600

700

800

100

120

140

160

Frequency/Amplitude vs Ramp

Rfreq=3.8K

e
qency

(

z
)

i
t
ude (

pp)

Ramp (K ohm)

Frequency

Amplitude

Oscillation frequency/Amplitude

vs. Resistance for set up frequency

Oscillation frequency/Amplitude

vs. Resistance for set up overlap

100

200

300

400

500

600

700

800

100

120

140

160

Frequency/Amplitude vs. Rfreq

Ramp=5K

eque

y (

z
)

Am
pl

i
t
ude (

App

)

Rfreq (K ohm)

Frequency

Amplitude

NJW4710

- 9 -

Ver.1

PACKAGE OUTLINE

SSOP24-E1

0. 15

0.10

0. 12

0
.
1

0
.
0

0 ~ 10°

- 0. 05

+ 0.1

0. 22 - 0.05

+ 0.1

0. 65

0.375TYP

7. 9 ± 0. 2

[CAUTION]

The specifications on this databook are only

given for information , without any

guarantee

as regards either mistakes or omissions. The
application circuits in this databook are

described only to show representative usages

of the product and not intended for the

guarantee or permission of any right

Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: NJW4710

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: NJW4710