Philips TDA1300TT, TDA1300T Datasheet

INTEGRATED CIRCUITS

DATA SH EET

TDA1300T; TDA1300TT

Photodetector amplifiers and laser
supplies

Preliminary specification
Supersedes data of 1995 Nov 16
File under Integrated Circuits, IC01

1997 Jul 15

Philips Semiconductors Preliminary specification

Photodetector amplifiers and laser
supplies

FEATURES

• Six input buffer amplifiers with low-pass filtering with
virtually no offset

• HF data amplifier with a high or low gain mode

• Two built-in equalizers for single or double speed mode

ensuring high playability in both modes

• Full automatic laser control including stabilization and
an on/off switch and containing a separate supply V
for power reduction

• Applicable with N-sub laser with N-sub or P-sub monitor
diode

• Adjustable laser bandwidth and laser switch-on current
slope

• Protection circuit preventing laser damage due to supply
voltage dip

• Optimized interconnect between pick-up detector and
TDA1301

• Wide supply voltage range

• Wide temperature range

• Low power consumption.

DDL

TDA1300T; TDA1300TT

GENERAL DESCRIPTION

The TDA1300 is an integrated data amplifier and laser
supply for three beam pick-up detectors applied in a wide
range of mechanisms for Compact Disc (CD) and read
only optical systems. It offers 6 amplifiers which amplify
and filter the focus and radial diode signals adequately and
provides an equalized RF signal for single or double speed
mode which can be switched by means of the speed
control pin.

The device can handle astigmatic, single Foucault and
double Foucault detectors and is applicable with all N-sub
lasers and N-sub or P-sub monitor diode units.

After a single initial adjustment the circuit keeps control
over the laser diode current resulting in a constant light
output power independent of ageing. The chip is mounted
in a small SO24 or TSSOP24 package enabling mounting
close to the laser pick-up unit on the sledge.

QUICK REFERENCE DATA

SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT

V

DD

supply voltage 3 − 5.5 V

Diode current amplifiers (n = 1 to 6)

G

d(n)

I

O(d)

B 3 dB bandwidth I

diode current gain 1.43 1.55 1.67
diode offset current −−100 nA

= 1.67 µA50−−kHz

i(d)

RFE amplifier (built-in equalizer)

t

d(eq)

t

d(f)

equalization delay fi= 0.3 MHz − 320 − ns
flatness delay double speed − 5 − ns

Laser supply

I

o(L)

output current V

=3V −−−100 mA

DDL

ORDERING INFORMATION

TYPE

NUMBER

NAME DESCRIPTION VERSION

PACKAGE

TDA1300T SO24 plastic small outline package; 24 leads; body width 7.5 mm SOT137-1
TDA1300TT TSSOP24 plastic thin shrink small outline package; 24 leads; body width 4.4 mm SOT355-1

1997 Jul 15 2

Philips Semiconductors Preliminary specification

Photodetector amplifiers and laser
supplies

BLOCK DIAGRAM

handbook, full pagewidth

I6

23 2

in

I6

20

I5

24

I4

22

I3

19

I2

6

I5

in

5

I4

in

4

I3

in

3

I2

in

2

1.5x

1.5x

1.5x

1.5x

1.5x

TDA1300T; TDA1300TT

Id6

Id5

Id4

Id3

Id2

out

out

out

out

out

O6

5

O5

1

O4

3

O3

6

O2

HG

LS

ADJ

V

DD

GND

I1

in

21

I1

11
12

14

17

MI

18
15

V
I

ADJ

V

I

mon

DD

mon

1

I

i(central)

(N-sub) or
(P-sub)

(N-sub) or

(P-sub)

SUPPLY

1.5x

95, 120, 134 or
240 kΩ

I/V

V

gap

OTA

−4

13

CL

Id1

TDA1300T

ILO

ON/OFF

out

10

16

MBG474

4

O1

9

RFE

RF

8

V

DDL

LO

7

LDON

Fig.1 Block diagram.

1997 Jul 15 3

Philips Semiconductors Preliminary specification

Photodetector amplifiers and laser
supplies

PINNING

SYMBOL PIN DESCRIPTION

O4 1 current amplifier 4 output
O6 2 current amplifier 6 output
O3 3 current amplifier 3 output
O1 4 current amplifier 1 output
O5 5 current amplifier 5 output
O2 6 current amplifier 2 output
LDON 7 control pin for switching the laser on

and off

V

DDL

RFE 9 equalized output voltage of sum signal

RF 10 unequalized output
HG 11 control pin for gain switch
LS 12 control pin for speed switch
CL 13 external capacitor
ADJ 14 P-sub monitor (if connected via

GND 15 ground (substrate connection)
LO 16 laser output; current output
MI 17 monitor diode input (laser)
V

DD

I2 19 photo detector input 2 (central)
I5 20 photo detector input 5 (satellite)
I1 21 photo detector input 1 (central)
I3 22 photo detector input 3 (central)
I6 23 photo detector input 6 (satellite)
I4 24 photo detector input 4 (central)

8 laser supply voltage

of amplifiers 1 to 4

resistor to GND);
N-sub monitor (if connected to V

18 supply

DD

TDA1300T; TDA1300TT

andbook, halfpage

)

1

O4

2

O6

3

O3

4

O1

5

O5

6

O2

TDA1300T

7

LDON

8

V

DDL

9

RFE

10

RF

11

HG

12

LS

MBG472

Fig.2 Pin configuration.

24

I4

23

I6

22

I3

21

I1

20

I5

19

I2

18

V

DD

17

MI

16

LO

15

GND

14

ADJ

13

CL

1997 Jul 15 4

Philips Semiconductors Preliminary specification

Photodetector amplifiers and laser
supplies

FUNCTIONAL DESCRIPTION

The TDA1300T; TDA1300TT can be divided into two main
sections:

• Laser control circuit section

• Photo diode signal filter and amplification section.

Laser control circuit section

The main function of the laser control circuit is to control
the laser diode current in order to achieve a constant light
output power. This is done by monitoring the monitor
diode. There is a fixed relation between light output power
of the laser and the current of the monitor diode. The circuit
can handle P-sub or N-sub monitor diodes.

N-sub

MONITOR

In this event pin 14 (ADJ) must be connected to the
positive supply voltage VDD to select the N-sub mode. With
an adjustable resistor (R
current can be adjusted (and so the laser light output
power) if one knows that the control circuit keeps the
monitor voltage V

at a constant level of

mon

approximately 150 mV.

) across the diode the monitor

ADJn

TDA1300T; TDA1300TT

R

ADJn

KG

B

----------------

N

× 8709–×10×≅

C

L

ext

in case of N-sub monitor, where
G

represents the AC gain of an extra loop amplifier,

ext

if applied, and K = ∆I
the laser/monitor unit. I

/∆IL which is determined by

mon

mon

(pin 17) at typical light emission power of the laser
diode.

• The third part is the power output stage, its input being
the integrator output signal. This stage has a separate
supply voltage (V

), thereby offering the possibility of

DDL

reduced power consumption by supplying this pin with
the minimum voltage necessary.

It also has a laser diode protection circuit which comes into
action just before the driving output transistor will get
saturated due to a large voltage dip on V
will result in a lower current of the laser diode, which
normally is followed immediately by an increment of the
voltage of the external capacitor CL. This could cause
damage to the laser diode at the end of the dip.
The protection circuit prevents an increment of the
capacitor voltage and thus offers full protection to the laser
diode under these circumstances.

(Hz)

is the average current

. Saturation

DDL

P-sub

MONITOR

In this event pin 14 (ADJ) is connected via resistor R

ADJp

to ground. The P-sub mode is selected and pin 14 (ADJ)
acts as reference band gap voltage, providing together
with R
circuit keeps the monitor current at a level which is 10l

an adjustable current l

ADJp

. Now the control

ADJ

ADJ

The circuit is built up in three parts:

• The first part is the input stage which is able to switch
between both modes (N-sub or P-sub).

• The second part is the integrator part which makes use
of an external capacitor CL. This capacitor has two
different functions:

– During switch-on of the laser current, it provides a

current slope of typically:

≅

10

----------­C

6–

(A/s)

L

∆I

o(L)

------------- ­t∆

– After switch-on it ensures that the bandwidth equals

KG

× 909–×10×

≅

B

P

ext

------------------------------------------------- -

×

C

LImon

(Hz)

in case of P-sub monitor or

Photo diode signal filter and amplification section

This section has 6 identical current amplifiers.
Amplifiers 1 to 4 are designed to amplify the focus photo
diode signals. Each amplifier has two outputs: an
LF output and an internal RF output. Amplifiers 5 and 6

.

are used for the radial photo diode currents and only have
an LF output. All 6 output signals are low-pass filtered with
a corner frequency at 69 kHz. The internal RF output
signals are summed together and converted to a voltage
afterwards by means of a selectable transresistance.

This transresistance R

can be changed between 140 kΩ

RF

(3.3 V application) or 240 kΩ (5 V application) in
combination with the P-sub monitor. In the event of the
N-sub monitor selection, RRF can be changed between
70 kΩ (3.3 V application) and 120 kΩ (5 V application).
The RF signal is available directly at pin 10 but there is
also an unfiltered signal available at pin 9.

The used equalization filter has 2 different filter curves:

• One for single-speed mode

• One for double-speed mode.

1997 Jul 15 5

Philips Semiconductors Preliminary specification

Photodetector amplifiers and laser
supplies

Table 1 Gain and monitor modes

PIN

HG ADJ

0R

connected

ADJp

to ground

0 1 N-sub 70

(1)

1

R

ADJp

connected

to ground

(1)

1

1 N-sub 120

Note

1. Logic 1 or not connected.

Table 2 Speed and laser modes; note 1

PIN

DEFAULT

VALUE

(2)

LS 1 1 0 X

LDON 1 X

MONITOR MODE R

P-sub 140

P-sub 240

SINGLE DOUBLE on off

(3)

TDA1300T; TDA1300TT

(kΩ) INTENDED APPLICATION AREA

RF

3.3 V

5V

MODE

SPEED LASER

(3)

(3)

X

10

(3)

X

Notes

1. 1 = HIGH voltage (V

); 0 = LOW voltage (GND); X = don’t care.

DD

2. If not connected.

3. X = don’t care.

LIMITING VALUES

In accordance with the Absolute Maximum Rating System (IEC 134).

SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT

V

DD

P

max

T

stg

T

amb

supply voltage − 8V
maximum power dissipation − 300 mW
storage temperature −65 +150 °C
operating ambient temperature

TDA1300T −40 +85 °C
TDA1300TT −40 +70 °C

(1)

V

es

electrostatic handling pin 16 note 2 −2+2kV
electrostatic handling (all other pins) −3+3kV

Notes

1. Classification A: human body model; C = 100 pF; R = 1500 Ω; V

= ±2000 V.

es

Charge device model: C = 200 pF; L = 2.5 µH; R = 0 Ω; Ves= 250 V.

2. Equivalent to discharging a 100 pF capacitor through a 1.5 kΩ series resistor.

1997 Jul 15 6