Block Diagram and Pin Configuration

--1--

E93717-TE

Read/Write Amplifier (with Built-in Filters) for FDDs

32 pin QFP (Plastic)

CXA1720Q

· Supply voltage detection circuit prohibits error

writing during power ON/OFF or abnormal voltage.

· Power consumption is kept down to 115 mW (typ.)

and this IC is suitable for use with battery-driven

FDDs.

· Built in Time constant capacitors for monostable

multivibrator Nos. 1 and 2. (The pulse width for

monostable multivibrator No. 2 is fixed.)

· Power saving function reduces power consumption

when the IC is not in use. When in power saving

mode (5 mW typ.), only the power supply ON/OFF

detector functions.

· The Write driver has a built-in reset circuit. When

the mode is switched from Read mode to Write

mode, the Write current flows from head 0A if head

side 0 is selected and from head 1A if head side 1

is selected.

Description

The CXA1720Q is an IC for use with floppy disk

drives, and contains a Read circuit (with built-in

filters), Write circuit, Erase circuit, and supply

voltage detection circuit, all into a single chip.

Features

· Single 5 V power supply.

· Filter system can be switched among four modes:

1M/2M, and inner track/outer track. This allows for

a significant reduction in the number of external

parts such as differentiator constants, low-pass

filters, and switches. (Compared with conventional

Sony products, the number of parts has been

reduced by one-half.)

· Filter characteristics can be customized.

· Low pre-amplifier input conversion noise voltage of

2.0 nV/

Hz (typ.) keeps Read data output jitter to

a minimum. The pre-amplifier voltage gain can be

selected as either 100

or 200

· The monostable multivibrator No. 1 pulse width

switching function for the time domain filter permits

switching between 1M and 2M mode.

· Write current switching function permits switching

of the Write current among four modes: 1M/2M

and inner track/outer track. (Filter inner track/outer

track switching is separate.)

FILTER

OUT B

COMP

IN B

COMP

IN A

A.GND

MMVA

FILTER

SET

Vcc

HIGH
DENSITY

POWER

WRITE

DATA

READ DATA

WRITE

CURRENT

WRITE

GATE

ERASE

GATE

SIDE 1

FILTER

CONTROL

W/C 1

SET

W/C 1

COMP

W/C 2

SET

W/C 2

COMP

ERASE

OUT 0

ERASE

OUT 1

HEAD 0A

HEAD 0B

HEAD 1A

HEAD 1B

PREAMP OUT

VREF

FILTER OUT A

WRITE

DRIVER

ERASE

DRIVER

POWER

MONITOR

CONTROL

LOGIC

TIME

DOMAIN

FILTER

COMP

FILTER

DIFF+LPF

(BPF)

HIGH

GAIN

D.GND

POWER

SAVE

PREAMP

Sony reserves the right to change products and specifications without prior notice. This information does not convey any license by
any implication or otherwise under any patents or other right. Application circuits shown, if any, are typical examples illustrating the
operation of the devices. Sony cannot assume responsibility for any problems arising out of the use of these circuits.

For the availability of this product, please contact the sales office.

--2--

CXA1720Q

Structure

Bipolar silicon monolithic IC

Absolute Maximum Ratings (Ta=25 °C)

· Supply voltage

· Digital signal input pin (note) input voltage

0.5 to V

+0.3

· Power ON output applied voltage

+0.3

· Erase output applied voltage

+0.3

· Head 0A, 0B, 1A, 1B applied voltage

· Power ON output sink current

· Erase output sink current

· Operating temperature

Topr

20 to +75

°C

· Storage temperature

Tstg

65 to +150

°C

· Allowable power dissipation

500

Supply Voltage Range

4.4 to 6.0

Note) WRITE DATA, WRITE CURRENT, WRITE GATE, ERASE GATE

SIDE1, FILTER CONTROL, HIGH DENSITY, HIGH GAIN, POWER SAVE

--3--

CXA1720Q

Pin Description

(Ta=25 °C, V

=5 V)

Vcc

A.GND

2.3V

Vcc

D.GND

140

Vcc

A.GND

100k

2.1V

Symbol

Pin voltage

Equivalent circuit

Description

No.

POWER ON

WRITE

DATA

READ

DATA

WRITE

CURRENT

WRITE

GATE

ERASE

GATE

SIDE1

FILTER

CONTROL

HIGH

DENSITY

HIGH

GAIN

Vcc

A.GND

100k

Reduced voltage detection output.

This is an open collector that outputs a low signal

when V

is below the specified value.

Write data input.

This pin is a Schmitt-type input and is triggered

when the logical voltage goes from high to low.

Read data output.

This pin is active when the logical voltage of the

Write gate signal and the Erase gate signal is high.

Write current control. The Write current is

increased when the logical voltage is low.

Write gate signal input. The Write system is active

when the logical voltage is low.

Erase gate signal input. The Erase system is

active when the logical voltage is low.

Head side switching signal input. The HEAD1

system is active when the logical voltage is low,

and the HEAD0 system is active when the logical

voltage is high, but only when the logical voltage

for the Write gate and the Erase gate is high.

Filter inner track/outer track mode control. Inner

track mode is selected when the logical voltage is

low.

Filter, time domain filter and Write current 1M/2M

mode control. 2M mode is selected when the

logical voltage is low.

Pre-amplifier voltage gain selection. Gain of 100x

is selected when the logical voltage is high; gain of

200x is selected when the logical voltage is low.

--4--

CXA1720Q

Vcc

A.GND

147

1.2V

Vcc

A.GND

147

10k

16k

60µ

Vcc

A.GND

140

500µ

140

500µ

Symbol

Pin voltage

Equivalent circuit

Description

No.

FILTER

SET

MMVA

A. GND

COMP IN A

COMP IN B

FILTER

OUT B

FILTER

OUT A

3.8 V

0.5 V

3.3 V

Vcc

A.GND

147

1.2V

Power supply (5 V) connection.

Connection for filter cut-off frequency setting

resistor. Connect the filter cut-off frequency setting

resistor R

between this pin and V

to set the cut-

off frequency.

Time domain filter monostable multivibrator No. 1

pulse width setting pin. Connect the monostable

multivibrator No. 1 pulse width setting resistor R

between this pin and A.GND.

Analog system GND connection.

Comparator differential inputs.

Filter differential outputs.

--5--

CXA1720Q

Vcc

A.GND

140

320µ

A.GND

23 22

Vcc

A.GND

1.2V

147

Vcc

A.GND

Symbol

Pin voltage

Equivalent circuit

Description

No.

VREF

PREAMP

OUT

HEAD 1B

HEAD 1A

HEAD 0B

HEAD 0A

W/C1SET

W/C2SET

W/C1

COMP

W/C2

COMP

2.8 V

Vcc

A.GND

500

120µ

Connection for internal reference voltage

decoupling capacitor. Connect the decoupling

capacitor CREF between this pin and A.GND.

Pre-amplifier output.

Connection for magnetic head input/output.

Connect the recording/playback magnetic head to

these pins, and connect the center tap to V

When the logical voltage for Pin 7 (SIDE1) is low,

the HEAD1 system is active; when the logical

voltage is high, the HEAD0 system is active.

Connection for 1M write current setting resistor.

Connect the Write current setting resistor R

between this pin and V

to set the Write current.

Connection for 2M Write current setting resistor.

Connect the Write current setting resistor R

between this pin and V

to set the Write current.

Connection for 1M Write current compensation

resistor.

Connect the Write current compensation resistor

WC1

between this pin and Pin 25 (W/C1SET) to

set the amount of increase in the Write current.

Connection for 2M Write current compensation

resistor.

Connect the Write current compensation resistor

WC2

between this pin and Pin 27 (W/C2SET) to

set the amount of increase in the Write current.

--7--

CXA1720Q

Electrical Characteristics

Current Consumption

(Ta=25 °C, V

=V)

Power Supply Monitoring System

(Ta=25 °C)

Read System

When SW4 = a: Vi = 10 mVp-p

When SW4 = b: Vi = 5 mVp-p

Measure- Measure-

Item

Symbol

Conditions

ment

Min.

Typ.

Max.

Unit

circuit

point

Current consumption for Read

ICCR

=5 V

13.0

23.0

33.0

WG="H"

Current consumption for

ICCWE

=5 V

8.0

14.0

20.0

Write/Erase

WG="L", EG="L"

Current consumption for

ICCPS

=5 V

0.9

1.8

Power saving

PS="L"

Measure- Measure-

Item

Symbol

Conditions

ment

Min.

Typ.

Max.

Unit

circuit

point

Power supply ON/OFF detector

VTH

3.5

3.9

4.3

threshold voltage

Power ON output saturation

VSP

=3.5 V

0.5

voltage

I=1 mA

Measure- Measure-

Item

Symbol

Conditions

ment

Min.

Typ.

Max.

Unit

circuit

point

Pre-amplifier voltage gain

GV0

f=100 kHz

SIDE0

SW4=a, b

38.1/

41.6/

Pre-amplifier voltage gain

f=100 kHz

44.1

40/46

47.6

SIDE1

GV1

SW4=a, b

SW1, 5=b

Pre-amplifier frequency response

BW0

=3 dB

SIDE0

SW4=a, b

Pre-amplifier frequency response

=3 dB

MHz

SIDE1

BW1

SW4=a, b

SW1, 5=b

Pre-amplifier input conversion

Bandwidth=400 Hz

noise voltage

EN0

to 1 MHz Vi=0,

SIDE0

SW4=b

Pre-amplifier input conversion

Bandwidth=400 Hz

2.0

2.9

Vrms

noise voltage

EN1

to 1 MHz

SIDE1

SW4=b

Vi=0, SW1, 5=b

--8--

CXA1720Q

Read System

(Ta=25 °C, V

=5 V)

When SW4 = a: Vi = 60 mVp-p

When SW4 = b: Vi = 30 mVp-p

Read data output between 0.5 V to 2.4 V

For Vi = 0.25 mVp-p to 5m Vp-p: SW4 = b (pre-amplifier voltage gain: 46 dB)

For Vi = 0.5 mVp-p to 10 mVp-p: SW4 = a (pre-amplifier voltage gain: 40 dB)

Measure- Measure-

Item

Symbol

Conditions

ment

Min.

Typ.

Max.

Unit

circuit

point

Pre-amplifier output offset voltage

Vi=0

(vs. VREF)

VOFSP SW4=a, b,

F, G

500

+500

SW1, 5=a, b

Pre-amplifier output voltage

f=100 kHz

amplitude

VOP

SW4=a, b,

1.8

Vp-p

SW1, 5=a, b

Filter differential output offset

VOFSF Vi=0

D, E

100

+100

voltage

Filter differential output voltage

VOF

f=100 kHz

D, E

2.8

Vp-p

amplitude

Vi=60 mVp-p

Time domain filter monostable

ETM1

=27 k

B, C

multivibrator No. 1 pulse width

ETM1'

Refer to Fig. 1

+10

precision

Time domain filter monostable

=27 k

multivibrator No. 2 pulse width

Refer to Fig. 1

260

400

540

(fixed)

Read data output low voltage

VOL

=2 mA

0.5

Read data output high voltage

VOH

=0.4 mA

2.8

Read data output

rise time

=2 k

100

=20 pF

Read data output

fall time

=2 k

100

=20 pF

Vi=0.25 mVp-p to

Peak shift

10 mVp-p

f=62.5 kHz

Refer to Fig. 1

--10--

CXA1720Q

Read System (Filters)

(Ta=25 °C, V

=5 V)

= 20Log

Filterout

Preout

)

Filterout

: Filter differential output voltage

(N=1 to 4)

Measure- Measure-

Item

Symbol

Conditions

ment

Min.

Typ.

Max.

Unit

circuit

point

Peak frequency

Vi=3mVp-p HG="L"

D, E

153.0

170.0

187.0

kHz

HD="H" FC="H"

Peak voltage gain

Refer to Fig. 2

3.6

5.5

7.1

1M/

at f

D, E

outer

Refer to Fig. 2

track

Frequency response (1)

D, E

7.6

7.1

6.6

Frequency response (2)

Refer to Fig. 2

D, E

25.0

23.1

21.5

at 3f

Vi=3mVp-p

Peak frequency

HG=":L"

D, E

163.8

182.0

200.2

kHz

HD="H" FC="L"

1M/

Peak voltage gain

Refer to Fig. 2

3.6

5.5

7.1

inner

at f

D, E

track

Refer to Fig. 2

Frequency response (1)

D, E

7.6

7.1

6.6

Frequency response (2)

Refer to Fig. 2

D, E

25.0

23.1

21.5

at 3f

Peak frequency

Vi=3mVp-p HG="L"

D, E

288.0

320.0

352.0

kHz

HD="L" FC="H"

Peak voltage gain

Refer to Fig. 2

3.6

5.5

7.1

2M/

at f

D, E

outer

Refer to Fig. 2

track

Frequency response (1)

D, E

7.6

7.1

6.6

Frequency response (2)

Refer to Fig. 2

D, E

25.0

23.1

21.5

at 3f

Peak frequency

Vi=3mVp-p HG="L"

D, E

310.5

345.0

379.5

kHz

HD="L" FC="L"

Peak voltage gain

Refer to Fig. 2

5.3

7.2

8.8

at f

D, E

inner

Refer to Fig. 2

track

Frequency response (1)

D, E

8.6

8.1

7.6

Frequency response (2)

Refer to Fig. 2

D, E

36.2

34.3

32.7

at 3f

--12--

CXA1720Q

Write/Erase System

(Ta=25 °C, V

=5 V)

Write current output precision

(

)

100 (%)

2.70 mA

Write current compensation current precision

(

)

100 (%)

0.90 mA

: WRITE CURRENT = "H" I

': WRITE CURRENT = "L"

Logic Input Block

Measure- Measure-

Item

Symbol

Conditions

ment

Min.

Typ.

Max.

Unit

circuit

point

Write current output precision

WG="L"

LKJI

=4.3 k

Write current output unbalance

WG="L"

LKJI

=4.3 k

Write current compensation current

WG="L"

precision

EWC

=4.3 k

LKJI

+10

=12 k

Head I/O pin leak current for Write

ILKW

WG="L"

LKJI

µA

Head I/O pin saturation voltage

VSW

WG="L"

L'K'J'I'

for Write

SW1=6

Leak current for Erase current

ILKE

EG="L"

µA

switch

Output saturation voltage for Erase

EG="L"

current switch

VSE

I=30 mA

M'N'

500

SW2=b

Measure- Measure-

Item

Symbol

Conditions

ment

Min.

Typ.

Max.

Unit

circuit

point

Digital low input voltage

VLD

BCDE

0.8

FGHP

Digital high input voltage

VHD

BCDE

2.0

FGHP

Schmitt-type digital low input

VLSD

0.8

voltage

Schmitt-type digital high input

VHSD

2.0

voltage

Digital low input current

ILD

=0 V

ABCD

EFGHP

µA

Digital high input current

IHD

=5 V

ABCD

EFGHP

--13--

CXA1720Q

Electrical Characteristics Measurement Circuit 1

Note) Unless otherwise specified, switches are assumed to be set to "a".

Electrical Characteristics Measurement Circuit 2

Note) Unless otherwise specified, switches are assumed to be set to "a".

FILTER

OUT B

COMP

IN B

COMP

IN A

A.GND

MMVA

FILTER

SET

Vcc

I
T

I
L

W/C 1

SET

W/C 1

COMP

W/C 2

SET

W/C 2

COMP

D.GND

ERASE

OUT 0

ERASE

OUT 1

I
L

CXA1720Q

0.1µ

SW4

1/2V 1

SW5

4.3k

12k

4.3k

12k

SW1

SW2

SW3

3.2k

27k

3300p

POWER
SAVE

HIGH

DENSITY

I
G

I
N

I
D

4.3k

12k

4.3k

12k

3.2k

27k

0.1µ

2.2k

SW1 a

2.2k

b a

FILTER

OUT B

COMP

IN B

COMP

IN A

A.GND

MMVA

FILTER

SET

Vcc

I
T

I
D

I
L

W/C 1

SET

W/C 1

COMP

W/C 2

SET

W/C 2

COMP

D.GND

ERASE

OUT 0

ERASE

OUT 1

I
L

CXA1720Q

100k

30mA

SW2

100k

30mA

I
G

I
N

POWER
SAVE

I
T

HIGH

DENSITY

--14--

CXA1720Q

Description of Operation

(1) Read system

Pre-amplifier

The pre-amplifier amplifies input signals. The voltage gain can be switched between 40 dB and 46 dB,

using Pin 20.

Filters

The filters differentiate the signals amplified by the pre-amplifier. The high-band noise components are

attenuated by the low-pass filter. The filters can be switched among four modes, depending on the

settings of Pins 8 and 9. In 1M/outer track mode, the peak frequency f

is set by external resistor R

for the other three modes is switched by the internal settings of the IC, with f

used as a reference

(1.00).

The filters are explained below.

1) Active filter block

Filter Characteristics

Table 1

The formula for the peak frequency f

for 1M/outer track mode is shown below:

= 527/R

+ 5.8 (kHz)

: peak frequency in 1M/outer track mode

: filter setting resistance (k

)

The relationship between f01 and f0 in the four modes is as follows:

1M/outer track: f

= 1.0

1M/inner track: f

= 1.07

2M/outer track: f

= 1.88

2M/inner track: f

= 2.03

Note that these filters can be customized.

Customization is explained on pages 17 and 18.

BPF

LPF

HPF

Amp.

Pre-amplifier output

Secondary

Tertiary

Primary

Filter output A

Filter output B

=1.2Xf

; variable

=5KHz

Gain; 8.0dB

Q=0.577

Q; variable

Pre-amplifier output

Pin 8

Pin 9

LPF characteristics

ratio

1M/outer track mode: Butterworth

1.00

1M/inner track mode: Butterworth

1.07

2M/outer track mode: Butterworth

1.88

2M/inner track mode: Chebyshev 1 dB ripple

2.03

--15--

CXA1720Q

Comparator

The comparator detects the crosspoint of the filter differential output.

Time domain filter

The time domain filter converts the comparator output to Read data.

This filter is equipped with two monostable multivibrators. Monostable multivibrator No. 1 eliminates

unnecessary pulses, and monostable multivibrator No. 2 determines the pulse width of Read data.

The monostable multivibrator No. 1 pulse width T

is determined by the resistor R

between Pin 12 and

A.GND. T

can be switched as follows by the setting of Pin 9:

HIGH DENSITY = "H"

A LOW

= 84R

+ 180 (nS)

)

HIGH DENSITY = "L"

A HIGH

= 42R

+ 110 (nS)

The pulse width for monostable multivibrator No. 2 is fixed at 400 ns.

(2) Write System

Write data input through Pin 2 is frequency-divided by the T flip-flop and generates the head recording

current. The recording current can be switched by the setting of Pin 9.

The Write current Iw is set by the resistor R

connected between Pin 25 and V

and between Pin 27 and

= 11.6/R

(mA)

)

Furthermore, the Write current compensation I

is set by the resistor R

connected between Pin 25 and Pin

26, and between Pin 27 and Pin 28.

= 10.8/R

(mA)

)

(3) Erase System

Pins 30 and 31 are open collector outputs; the Erase current is set by the resistance between these pins

and the Erase head.

(4) Power ON/OFF Detection System

The power ON/OFF detection system detects a reduced voltage.

When V

is below the stipulated voltage, the Write system and Erase system cease operation, disabling

the Write and Erase functions

Notes on Operation

· Select the voltage gain so that the pre-amplifier output amplitude is 1 Vp-p or less.

If the pre-amplifier output amplitude exceeds 1 Vp-p, the filter output waveform becomes distorted.

· Observe the following points when mounting this IC.

· Connect a V

decoupling capacitor of approximately 0.1 µF close to the IC.

· The ground should be as large as possible.

--16--

CXA1720Q

Application Circuit (for 1M/2M devices)

FILTER

OUT B

COMP

IN B

COMP

IN A

A.GND

MMVA

FILTER

SET

Vcc

HIGH
DENSITY

POWER

WRITE

DATA

READ

DATA

WRITE

CURRENT

WRITE

GATE

ERASE

GATE

SIDE 1

FILTER

CONTROL

W/C 1SET

W/C 1COMP

W/C 2

SET

W/C 2

COMP

D.GND

ERASE

OUT 0

ERASE

OUT 1

POWER

SAVE

HEAD

PREAMP

OUT

VREF

FILTER

OUT A

WRITE

DRIVER

ERASE

DRIVER

POWER

MONITOR

CONTROL

LOGIC

I
M

I
N

I
L

FILTER

DIFF+LPF

(BPF)

PREAMP

27k

3.2k

3300P

REF

0.1µ

HEAD

HIGH
GAIN

Application circuits shown are typical examples illustrating the operation of the devices. Sony cannot assume responsibility for
any problems arising out of the use of these circuits or for any infringement of third party patent and other right due to same.

--18--

CXA1720Q

Filter Customization Selections/Combinations

In filter settings, use the LPF cut-off frequency f

in 1M/outer track mode as 1.00 as shown in Table 1 to

select fc ratios and LPF types for the other three modes. The 1M/outer track to 2M/outer track modes for the

LPF are fixed to Butterworth, while either Butterworth or Chebyshev 1 dB ripple can be selected in 2M/inner

track mode.

Note that the BPF center frequency f

is fixed at 1.2 times the LPF cut-off frequency fc. In addition, the

relationship between the peak frequencies fo and fc in regards to the comprehensive characteristics is as

follows, depending on differences in LPFs.

Butterworth characteristics:

= 1.28fo

Chebyshev 1 dB ripple characteristics:

= 1.12fo

Table 1 LPF fc Ratios and Types

Note) The boxed item indicates the setting for the CXA1720Q.

Mode

LPF type

ratio when f

is assumed as 1.00

1M/outer track

Butterworth

1.00

1.07

1.14

1.23

1.33

1.45

1M/inner track

Butterworth

1.60

2.00

1.33

1.39

1.45

1.52

1.60

2M/outer track

Butterworth

1.68

1.78

1.88

2.00

2.13

2.29

2.46

2.67

Butterworth

1.33

1.39

1.45

1.52

1.60

2M/inner track

Chebyshev

1.68

1.78

1.88

2.00

2.13

(1 dB ripple)

2.29

2.46

2.67

--19--

CXA1720Q

Normalized pre-amplifier voltage gain and phase vs. Frequency

Vcc=5V, Ta=25°C
When HD=high, low

r
m

l
i
z

r
e

-
a

l
i
f
i
e

r

v

l
t
a

i
n

(
d

)

f-Frequency (Hz)

(
d

r
e

)

Phase

Voltage Gain

Filter characteristics in the four modes
(These characteristics are based on pre-amplifier output. 0dB=pre-amplifier output
level)

10k

100k

10M

100M

120

150

1M/outer track

r
m

l
i
z

f
i
l
t
e

r

v

l
t
a

i
n

(
d

)

=170 (KHz) Frequency (Hz)

(
d

r
e

)

Voltage gain

Phase

10k

50k

100k

300k

20
30

50
60

200

150

100

200

150

1M/inner track

r
m

l
i
z

f
i
l
t
e

r

v

l
t
a

i
n

(
d

)

=182 (KHz) Frequency (Hz)

(
d

r
e

)

Voltage gain

Phase

10k

50k

100k

300k

40
50

200

150

100

200

150

2M/outer track

r
m

l
i
z

f
i
l
t
e

r

v

l
t
a

i
n

(
d

)

=320 (KHz) Frequency (Hz)

(
d

r
e

)

Voltage gain

Phase

10k

50k

100k

300k

20
30

60
70

200

150

100

200

150

2M/inner track

r
m

l
i
z

f
i
l
t
e

r

v

l
t
a

i
n

(
d

)

=345 (KHz) Frequency (Hz)

(
d

r
e

)

Voltage gain

Phase

10k

50k

100k

300k

20
30

60
70

200

150

100

200

150

=5V, Ta=25°C

=3.2k

=5V, Ta=25°C

=3.2k

=5V, Ta=25°C

=3.2k

=5V, Ta=25°C

=3.2k

--20--

CXA1720Q

Normalized pre-amplifier voltage gain+filter voltage gain

vs. Ambient temperature

Ta-Ambient temperature (°C)

f=100KHz Vcc=5V
Vin=10mVp-p (HG="H")
Vin=5mVp-p (HG="L")
NGV=GV/GV (Ta=25°C)

1.50

1.00

0.50

Normalized pre-amplifier voltage gain+filter voltage gain

vs. Supply voltage

Vcc-Supply voltage (V)

Ta=25°C
f=100KHz
Vin=10mVp-p (HG="H")
Vin=5mVp-p (HG="L")
NGV=GV/GV (Vcc=5V)

1.50

1.00

0.50

4.0

5.0

6.0

3.2k

Vcc

Normalized monostable multivibrator No. 1 pulse width

vs. Ambient temperature

-
N

r
m

l
i
z

t
a

l
e

l
t
i
v

i
b

r
a

t
o

.

1

l
s

i
d

t
h

Ta-Ambient temperature (°C)

Vcc=5V
NTA=TA/TA (Ta=25°C)
When HD=high, low

1.05

1.00

0.95

27k

3.2k

Vcc

-
N

r
m

l
i
z

r
e

-
a

l
i
f
i
e

r

v

l
t
a

i
n

f
i
l
t
e

r

v

l
t
a

i
n

-
N

r
m

l
i
z

r
e

-
a

l
i
f
i
e

r

v

l
t
a

i
n

f
i
l
t
e

r

v

l
t
a

i
n

--21--

CXA1720Q

Monostable multivibrator No. 1 pulse width vs. R

-
M

t
a

l
e

l
t
i
v

i
b

r
a

t
o

r

N

.

1

l
s

i
d

t
h

(
µ

)

Vcc=5V
Ta=25°C

100

Vcc-Supply voltage (V)

1.05

1.00

0.95

4.0

5.0

6.0

Normalized read data pulse width

vs. Ambient temperature

-
N

r
m

l
i
z

r
e

t
a

l
s

i
d

t
h

Ta-Ambient temperature (°C)

Vcc=5V
NTB=TB/TB (Ta=25°C)

1.05

1.00

0.95

27k

Normalized monostable multivibrator No. 1 pulse width

vs. Supply voltage

-
N

r
m

l
i
z

t
a

l
e

l
t
i
v

i
b

r
a

t
o

.

1

l
s

i
d

t
h

Ta=25°C
NTA=TA/TA (Ta=25°C)
When HD=high, low

0.3

A LOW

=84R

180 (ns)

A HIGH

=42R

110 (ns)

)

LOW

HIGH

--22--

CXA1720Q

Normalized write current vs. Ambient temperature

I
W

-
N

r
m

l
i
z

r
i
t
e

r
r
e

Ta-Ambient temperature (°C)

Vcc=5V
NIW=IW/IW (Ta=25°C)

1.05

1.00

0.95

Normalized read data pulse width

vs. Supply voltage

-
N

r
m

l
i
z

r
e

t
a

l
s

i
d

t
h

Vcc-Supply voltage (V)

Ta=25°C
NTB=TB/TB (Vcc=5V)

1.05

1.00

0.95

4.0

5.0

6.0

Normalized write current vs. Supply voltage

I
W

-
N

r
m

l
i
z

r
i
e

t

c

r
r
e

Vcc-Supply voltage (V)

1.05

1.00

0.95

4.0

5.0

6.0

WC1

WC2

12k

4.3k

Vcc

WC1

WC2

12k

4.3k

Vcc

Ta=25°C
NIW=IW/IW (Vcc=5V)

--23--

CXA1720Q

Normalized write compensation current vs.

Ambient temperature

I
W

-
N

r
m

l
i
z

r
i
t
e

t
i
o

r
r
e

Ta-Ambient temperature (°C)

Vcc=5V
NIWC=IWC/IWC (Ta=25°C)

1.05

1.00

0.95

Write current vs. RW

I
W

-
W

r
i
t
e

r
r
e

t

(
m

)

Rw (k

)

Vcc=5V
Ta=25°C
IW=11.6/Rw (mA)

Rw (k

)

10.0

5.0

1.0

10K

Normalized Write compensation current vs.

Supply voltage

I
W

-
N

r
m

l
i
z

r
i
e

t

c

t
i
o

r
r
e

Vcc-Supply voltage (V)

1.05

1.00

0.95

4.0

5.0

6.0

WC1

WC2

12k

4.3k

Vcc

WC1

WC2

12k

4.3k

Vcc

Ta=25°C
NIWC=IWC/IWC (Vcc=5V)

Vcc

--24--

CXA1720Q

Power supply ON/OFF detector threshold voltage vs.

Ambient temperature

-
P

r

s

l
y

/
O

t
e

t
o

r

t
h

r
e

l
d

l
t
a

(
V

)

Ta-Ambient temperature (°C)

4.2

3.9

3.7

Write current compensation vs. Rwc

I
W

-
W

r
i
t
e

r
r
e

t

c

t
i
o

(
m

)

Rwc (k

)

Vcc=5V
Ta=25°C
IWC=10.8/Rwc (mA)

Rwc (k

)

10.0

1.0

0.1

1.0

10.0

100.0

Normalized filter peak frequency vs.

Ambient temperature

f
0

-
N

r
m

l
i
z

f
i
l
t
e

r

p

f
r
e

1.05

1.00

0.95

4.0

5.0

6.0

3.2k

Vcc

Vcc=5V
Nf

(Ta=25°C)

)

WC1

WC2

4.3k

Vcc

ON threshold voltage

OFF threshold voltage

4.1

4.0

3.8

Ta-Ambient temperature (°C)

Ð­Ð»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: CXA1720Q

ÐÐ»ÐµÐºÑ‚Ñ€Ð¾Ð½Ð½Ñ‹Ð¹ ÐºÐ¾Ð¼Ð¿Ð¾Ð½ÐµÐ½Ñ‚: CXA1720Q