HIT HA12220F Datasheet

HA12220F

CD-ROM Drive Head Amplifier IC

ADE-207-230 (Z)

Target Specification

1st. Edition

April 1997

Functions

• RF amplifier (Built-in equalizer changing cir cuit)

• Focus error amplifier (fc = 60kHz Typ)

• Tracking error amplifier (Built-in cut-off frequency changing circuit fc = 30kHz, 60kHz, 100kHz,

200kHz Typ)

• FOK detection circuit (Built-in Vth changing circuit)

• Mirror detection circuit

• Defect detection circuit

• APC amplifier

• RFAGC amplifier

Features

• Built-in variable resistors (+14 to –16% 2% steps) for adjusting tracking error EF balance

• Built-in variable resistors (–8 to +8dB 4dB steps) for rough adjusting tracking gain

• Built-in variable resistors (–8 to +8dB 4dB steps) for rough adjusting focus gain

• Built-in focus offset insertion cir cuit (–0.7 to +0.7V in 0.1V steps)

• RF amplifier frequency characteristics 30MHz (–3dB) in case of peaking off

• High-speed access support (The mirror circuit internal time constant can be switched between normal, 4× and 8× modes.)

• Support for CD-RW playback

• Few external components

• Available to set the stand-by mode

• FP-28TB package

HA12220F

Block Diagram

RF2

1

RF3

2

RF4

3

GND

28

RF1

27

V

CC

BIAS

EQ

– +

26

RFS

–

+

0.1µ

BYPS

FE

10µ

+

25

+ –

– +

FSA

FVR2

GND 23

VCF RFC

VCB

FOK + –

FA2

+ –

Offset

1µ

+

24

AGC

Gain changing

Gain=12dB Typ

FA

+ –

FVR

0.1µ

AGCF

HD49250

22

AGCO

0.015µ

21

DFH

DEFECT

MIRR

DFT

MIRH

MIRR

FOK

20

HD49250

19

0.033µ

18

HD49250

GND

17

HD49250

TR1

APC

+

+ –

BAL

+ –

–

TR2

LD

7

TVR

TE

8

HD49250

TR1

4

TR2

5

MD

6

Rev.1, Apr. 1997, page 2 of 20

FE

TA

11

+

CO

–

100µ

+ –

XLT

DATA

16

HD49250

15

HD49250

VC

IIL

Interface

12 13 1410

XRST

+

µ-COM

CLK

HD49250

TE

+

TLPF

–

9

CI

µ-COM

ADC

+

TVR2

–

Gain=8dB Typ

BUF

GND

µ-COM

DAC

HA12220F

Pin Description and Equivalent Circuit

Pin No. Pin Name Equivalent Circuit Function

1RF2

28

12k 120k 160k

12k

1

120k 160k

12k

2

120k 160k

12k

3

120k 160k

5p

10p

4k

600k

160k

10p

2 RF3 RF FE FSA amplifier input3 3 RF4 RF FE FSA amplifier input4 28 RF1 RF FE FSA amplifier input1 4TR1

4k

1.2p

RF FE FSA amplifier input2

TR1 amplifier input

5TR2

6MD

7LD

8TE

150k

4k

32k80k

40k 11.4k

1.2p

32k80k

40k 11.4k

4k

1k

40k

TR2 amplifier input

APC amplifier input

APC amplifier output

Tracking error signal output

9 FE Focus error signal output

Rev.1, Apr. 1997, page 3 of 20

HA12220F

Pin Description and Equivalent Circuit (cont)

Pin No. Pin Name Equivalent Circuit Function

10 CI

2.5k

FSA amplifier output monitor

11 CO

12 VC

13 XRST

10k

20k

4k

Setting FOK reference voltage

Reference voltage output

Reset input

14 CLK Serial data synchronous clock

input 15 DATA Serial data input 16 XLT Serial data latch input

V

20k

10k

CC

V

CC

FOK detection signal output

Mirror detection signal output

17 FOK

18 MIRR

19 MIRH

20 DFT

Rev.1, Apr. 1997, page 4 of 20

100k

20k

Mirror envelope hold signal

output

V

CC

Defect detection signal output

Pin Description and Equivalent Circuit (cont)

Pin No. Pin Name Equivalent Circuit Function

21 DFH

Defect envelope hold signal

output

HA12220F

22 AGCO

23 AGCF

24 RFC

25 VCF

26 BYPS

5k 5k

100k 4k

2k 4k

20k

AGC amplifier output

Capacitor connection for AGC

V

CC

40k

4k

40k

GND

V

CC

Capacitor connection for

reference voltage ripple filter

Capacitor connection for ripple

filter

27 V

CC

—V

CC

Rev.1, Apr. 1997, page 5 of 20

HA12220F

Operation

Control by Serial Data

The IC’s internal switches can be operated by sending control data from the HD49250. The signal timing is shown in figure 1, and the control commands are listed in table 1 and 2.

DATA

Pin 15

Pin 14

CLK

01234567

T1

T2

Pin 16

XLT

Item Clock frequency Clock pulse width Delay time Latch pulse width

Symbol f

CLK

T1, T2 T3 T4

T3

Min Typ Max Unit

—

520

—

0.96 1 2

—

T4

kHz

µs µs µs

Figure 1 Timing Diagram for Serial Data Control

Signals from the HD49250 are input at pins 14 to 16. Pin13 is connected to the microcomputer. A low input at the XRST pin resets the IC. Normally this pin should be kept high.

The serial data from the HD49250 switches the followin g settings.

1. Tracking error EF balance

2. Focus offset

3. Tracking gain, Focus gain

4. FOK Vth

5. Mirror circuit, defect circuit normal speed / 4× speed / 8× speed mode

6. Tracking error cut-off frequency

7. APC amplifier ON/OFF

8. RF equalizer

9. Stand-by mode (cleared by setting XRST on)

Rev.1, Apr. 1997, page 6 of 20