SONY CXA3510N

CXA3510N
4ch. Read/Write Amplifier for
Thin Film Head of Hard Disk Drive
For the availability of this product, please contact the sales office.
Description
The CXA3510N is a Read/Write Amplifier for the
thin film head of hard disk drive and designed to
handle up to 4 channel heads.
Features
• Operate on single +5 V power supply
• Low power consumption
Read : 85 mW
Write : 115 mW + IW × 5
Idle : 8 mW
• Designed for two terminal thin-film or MIG heads
• Read amplifier emitter follower output featuring
360 times gain (typ).
• Differential input capacitance for Read : 6pF (typ)
• Input noise : 0.47 nV / √ Hz (typ)
• Write current range : 5 to 15 mA
• Differential Head voltage swing : 9 Vp-p (typ)
• IW Rise / Fall times : 3.7 ns (typ)
•
•
•
•
•
•
•
•
(LH=540 nH, RH=25 Ω, IW=10 mA)
Differential P-ECL write data input
Built-in write unsafe detection circuit.
Built-in Servo write function (2/4 ch).
Built-in IC protection circuit for short of head to
GND.
Read data outputs are high impedance in write
mode.
Unselected head voltage is GND potential.
Built-in supply voltage monitor circuit prohibits
incorrect write during power on or abnormal
voltage.
Self switching damping resistance (RD = 360 Ω).
20 pin SSOP (Plastic)
Absolute Maximum Ratings (Ta=25 °C)
• Supply voltage
VCC
6
V
• Write current
IW
20
mAo-p
• Operating temperature Topr
–20 to +75
°C
• Storage temperature
Tstg –55 to +150 °C
• Allowable power dissipation
PD
620
mW
• WUS/SE pin input current
ISEH
15
mA
Recommended Operating Conditions
• Supply voltage
VCC
5.0 V±10
%
• Write current
IW
5 to 15 mAo-p
Function
Read, Write and Write unsafe detection for HDD,
power supply ON/OFF detection.
Structure
Bipolar silicon monolithic IC
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.
—1—
E99201
CXA3510N
Block Diagram and Pin Configuration
GND
1
20
XCS
MODE
CONTROL
H0X
2
H0Y
3
H1X
4
19 R/W
DRIVER
WRITE
CURRENT
SOURCE
AMP
18 WC
17
RDY
16
RDX
DRIVER
AMP
H1Y
5
H2X
6
AMP
15 HS0
DRIVER
HEAD
SELECT
H2Y
7
H3X
8
AMP
14 HS1
13
WDX
12
WDY
DRIVER
IC
PROTECTOR
H3Y
9
VCC
10
AMP
POWER
ON/OFF
DETECTOR
WRITE
UNSAFE
DETECTOR
—2—
11 WUS/SE
CXA3510N
Pin Description
No.
Symbol
1
GND
Description
Equivalent circuit
2
VCC
4
2
3
4
5
6
7
8
9
H0X
H0Y
H1X
H1Y
H2X
H2Y
H3X
H3Y
6
8
2k
2k
Head.
4 channels provided.
3
5
7
9
100k
GND
10
VCC
5 V power supply.
VCC
11
Write unsafe detection output /
Servo Enable signal input.
11
WUS/SE
GND
VCC
12
13
WDY
WDX
12
Differential P-ECL write data
input.
13
GND
—3—
CXA3510N
No.
Symbol
Description
Equivalent circuit
VCC
14
15
HS1
HS0
Head select signal input.
Selects one of 4 heads according
to Table 2.
14
15
2.1V
100k
GND
VCC
16
17
16
RDX
RDY
Read Amplifier output.
17
GND
VCC
18
A setting resistor for the write
current value is connected
between this pin and GND.
WC
18
2.5V
GND
VCC
Read/Write signal input
At “High” : Read,
at “Low” : Write.
100k
19
R/W
19
2.1V
GND
VCC
20
XCS
Power save signal input
At “High” : Power saving.
20
2.1V
100k
GND
—4—
—5—
3-2
3-1
2-8
2-7
2-6
2-5
2-4
2-3
2-2
2-1
1-3
1-2
1-1
No.
Current consumption
for Read
Current consumption
for Write
Current consumption
for idle
Digital input “Low”
input voltage
Digital input “High”
input voltage
Digital input “Low”
input current
Digital input “High”
input current
Write data input
“Low” input voltage
Write data input
“High” input voltage
Write data
input current
Unselected
head voltage
Write unsafe output
saturation voltage
Write unsafe output
leak current
Item
Electrical Characteristics
a
ICCI
b
a
IWUS
a
a
VWUS
Vunsel
IWD
VWDH
VWDL
IIH
IIL
VIH
a
a
ICCW
VIL
a
1
ICCR
Symbol
a
a
a
a
a
a
a
a
2
a
a
a
a
a
a
a
a
3
a
a
a
a
a
a
a
a
4
a
b
a
a
a
a
a
a
5
a
b
b
b
b
b
b
b
a
a
a
a
a
a
a
a
a
c
a
a
a
a
a
a
b
c
b
b
b
b
b
b
a
c
a
b
a
a
a
a
a
c
a
b
a
a
a
a
b
b
b
b
b
b
b
b
a
a
a
b
a
a
a
b
a
a
a
b
a
b
a
a
SW conditions
6 7 8 9 10 11 12 13 14
Test point : l3
Output current : 1 mA
Test point : V1
Input voltage : 4 V
“High” applied voltage : 5 V
“Low” applied voltage : 0 V
Test point : l6, l7, l8, I9
Digital input :
Pins 14, 15, 19, 20
Test point : I2
Test point : l2
Test point : l2
Measurement conditions
VWDH
–2.0
VCC
–1.1
–100
2.0
1.6
50
0.5
0.3
50
VWDH
–0.25
VCC
–0.4
100
0.8
2.3
22
+IW
16
+IW
1.0
36
+IW
17
11
26
µA
V
V
µA
V
V
µA
µA
V
V
mA
mA
mA
Min. Typ. Max. Unit
(Unless otherwise specified, VCC=5 V, Ta=25 °C, Write current IW=15 mA)
Refer to Fig.1
CXA3510N
AW
KW
Write current gain
Write current
setting constant
WUS/SE voltage
5-3
5-4
6-1
6-2
a
a
a
4
a
a
b
a
a
b
a
a
b
a
a
b
a
a
b
b
a
a
a
a
IW=AW • VWC/RWC
V and IW starts to flow, VCC voltage
is set to VTHON.
Write mode and IW does not flow
anymore, VCC voltage is set to
VTHOFF. When VCC is raised from 3
When VCC is lowered from 5 V in
Measurement conditions
3.4
b
b
a
a
a
a
IW=KW/RWC
—6—
b
b
a
a
a
a
a
a
c
c
b
b
a
a
a
a
b
b
a
a
a
a
b
b
b
b
a
a
Input voltage SG1 :
1 mVp-p, 300 kHz
Load resistance (RDX, RDY) :
1 kΩ
Test point : V4 [Vp-p]
V4
AV =
SG1
Frequency at which AV lowers
by 3 dB
BW
a
a
Frequency band
width (–3 dB)
a
a
8
b
b
AV
a
a
Read amplifier
differential voltage gain
b
a
7
b
b
Servo write enabled
a
a
ISEH
a
a
WUS/SE sink current
a
a
Servo write enabled
a
a
VSEH
b
b
100
305
5
VCC
+1.5
45
18
140
360
50
20
2.5
3.9
V
mAo-p
V
415
14
VCC
+1.6
55
MHz
V/V
mA
V
22 mA/mA
2.75
15
4.3
Min. Typ. Max. Unit
2.25
a
a
3
VWC
a
a
2
5
Write current voltage
b
1
SW conditions
5 6 7 8 9 10 11 12 13 14
IW
5-2
VTH
Symbol
Write current
setting range
Supply power
ON/OFF detector
threshold voltage
Item
5-1
4
No.
CXA3510N
Input referred noise
Common mode
rejection ration
Power supply
rejection ratio
10
11
Item
9
No.
PSRR
CMRR
EN
Symbol
a
b
a
1
a
a
a
2
a
a
a
3
a
a
a
4
a
d
a
a
b
b
a
a
a
a
a
a
b
b
b
a
a
a
a
a
a
b
b
b
b
b
b
a
a
a
SW conditions
5 6 7 8 9 10 11 12 13 14
EN =
VN
100 • AV√ 15 × 106
Test point : V5
In-phase input voltage
SG2 : 100 mVp-p, 20 MHz
When the Read amplifier output is
VCM [mVp-p],
100
CMRR = 20 log
VCM
+20 log AV
Test point : V4
Ripple voltage SG3 :
100 mVp-p, 20 MHz
When the Read amplifier output is
VP [mVp-p],
100
PSRR = 20 log
VP
+20 log AV
Test point : V4
Head impedance : 0 Ω,
when the read amplifier output
voltage is amplified 100 times
and voltage passed though a LPF
(low pass filter of cutoff frequency
15 MHz) is VN [Vrms],
Measurement conditions
50
50
0.47
0.6
dB
dB
nV
√ Hz
Min. Typ. Max. Unit
CXA3510N
—7—
—8—
15
14
13
12
No.
RDX, RDY common
mode output voltage
for Read
Read data output
offset voltage for Read
RDX, RDY common
mode output voltage
difference between
modes
Channel
separation
Item
VRD
Vdiff
VOFFR
CS
Symbol
a
a
a
a
1
a
a
a
b
2
a
a
a
a
3
a
a
a
a
4
e
e
e
c
b
b
b
b
a
a
a
a
a
a
a
a
b
b
b
b
a
a
a
a
a
a
a
a
a
b
a
b
b
c
b
b
a
a
a
a
SW conditions
5 6 7 8 9 10 11 12 13 14
Test point : V2, V3
Test point : Pin 16, 17
Selected head input voltage
: 0 mVp-p
Unselected head input voltage
SG1 : 100 mVp-p, 20 MHz
When the Read amplifier output
is VCS [mVp-p],
100
CS = 20 log
VCS
+20 log AV
Test point : V4
VOFFR = V2–V3
Test point : V2, V3
Measurement conditions
VCC
–2.6
–300
–250
50
VCC VCC
–2.3 –2.0
300
250
V
mV
mV
dB
Min. Typ. Max. Unit
CXA3510N
CXA3510N
Unless otherwise specified, VCC=5 V, Ta=25 °C, fWD (Write data frequency) =5 MHz, IW=15 mA, LH (Head
inductance) =1 µH, RH (Head DC resistance value) =30 Ω
Refer to Fig. 2 to Fig. 4
No.
14
Item
Head differential
voltage amplitude
Mode switching time
15-1
Read to Write
Symbol
Measurement conditions
VSW
Differential voltage between HX pin and HY pin
at switching of Write current
TRW
Mode switching time
Write to Read
TWR2
16
Mode switching time
Power saving
to Read
TIR
17-1
Mode switching time
safe to unsafe
TSA1
17-2
Mode switching time
unsafe to safe
TSA2
18
Head switching time
TH
19
Write current
propagation delay
time
TPD
Write current
20-1
rise/fall time
TR/TF
Write current
rise/fall time
TR/TF
20-2
9
Vp-p
TRW is the time required for Write current to turn
TWR1
15-2
Min. Typ. Max. Unit
to 90 % after Pin 19 changes from “High” to
“Low”.
TWR1 is the time required for the Read amplifier
output∗ to turn to 90 % after Pin 19 changes
from “Low” to “High”.
TWR2 is the time required for Write current to
decreases to 10 % after Pin 19 changes from
“Low” to “High”.
TIR is the time required for the Read amplifier
output∗ to turn to 90 % after Pin 20 changes
from “High” to “Low”.
TSA1 is the time required for Pin 11 to turn
“High” after the last transition of Write data
1.0
when Write data is stopped in Write mode.
TSA2 is the time required for Pin 11 to turn “Low”
after the first transition of Write data in Write
mode.
TH is the time required for the Read amplifier
output∗ to reach 90 % when the selected head
switched in Read mode.
TPD is the time required for Write current to
reach 90 % after the Write data falling edge.
TR is the time required for Write current to reach
90 % from 10 %; TF is the same time required
to reach 10 % from 90 %. LH=0 µH, RH=0 Ω
LH=540 nH, RH=25 Ω, IW=10 mA
TR is the time required for Write current to reach
90 % from 10 %; TF is the same time required
to reach 10 % from 90 %.
∗Read amplifier output 100 mVp-p 10 MHz
—9—
130 150
ns
180 220
ns
100 200
ns
1
µs
3.0
µs
0.6
µs
0.6
µs
2
7
ns
1
3
ns
2.3
3.7
ns
CXA3510N
Test Circuit 1
VCC
5V
1µ
1k
1k
×100
LPF
A
AMP
to15MHz
V
AMP
S6
V
1µ
V4
PG
1µ
PG
b a
S13
A
a b
S12
A
I9
b a
a b
S11
4V
abc
S10
A
3.3k
I8
a b
abc
S9
A
I7
S8
A
I6
A
I5
I3
18
17
16
15
14
13
12
11
1
2
3
4
5
6
7
8
9
10
a b
a b
a b
S3
a b
a b
V1
A
I4
19
S2
V
S7
20
S1
S4
a b
a b
a b
S5
a b c
d
e
A
a b c d
e
0.1µ
I1
Fig. 1
SG2
33
0.1µ
6.5V
I14
V
3V
S14
A
SG4
V2
V
a b c
5.1k
PG
SG5
V3
SG6
5V
a b
I2
SG3
a b
×1
V5
VCC
5V
0.1µ
SG1
Test Circuit 2
1k
1k
×1
AMP
1µ
1µ
1µ
PG
PG
20
19
18
17
16
1
2
3
4
5
PG
PG
PG
15
14
13
12
11
6
7
8
9
10
3.3k
LH
LH
LH
LH
1µH
1µH
1µH
1µH
—10—
5.1k
5V
Fig. 2
CXA3510N
Timing Chart 1
WDX
WDY
R/W
50%
50%
50%
PS
TRW
TWR 2
90%
90%
IWX
IWY
10%
10%
TWR1
TIR
90%
RDX
RDY
90%
Fig. 3
Timing Chart 2
WDX
WDY
TPD
IWX
IWY
90%
90%
10%
10%
TR
WUS
90%
TF
50%
TSA1
50%
TSA2
Fig. 4
—11—
CXA3510N
Description of Functions
Read amplifier
This is a low noise amplifier for amplifying the signals from the heads with an emitter follower output.
The RDX and RDY are the outputs of the differential amplifier whose polarity between the RDX and X side of
the head input is same.
Write circuit
The Write data input to WDX pin and WDY pin passes through the buffer amp. It drives the Write switch
circuit which supplies the Write current to the heads.
The Write current flows into the X side when WDX is “Low” and WDY is “High”.
Mode control
The mode are set as shown Table 1 by XCS, R/W and WUS/SE.
XCS
R/W
WUS/SE
HS0 HS1
L
L
X
See Table 2
L
H
X
L
L
∗∗
See Table 3
H
X
X
X
X
Table 1. Mode selection
Mode
Write
Read
Servo Write
Power saving
Head selection
The heads are selected as shown in Table 2 by the HS0 and HS1 pins.
HS0
HS1
Head
L
L
0
H
L
1
L
H
2
H
H
3
Table 2. Head selection
Servo write mode ∗∗
This mode allows for writing to multiple channels at once.
To enable servo write mode follow these steps:
(1) Place the device in the Read mode.
(2) Set HS0 and HS1 following Table 3.
(3) Set WUS/SE to VSEH, or input ISEH to WUS/SE.
(4) While maintaing step (2) and (3) above make R/W low, placing the device in servo write mode.
—12—
CXA3510N
Write unsafe detection circuit
This circuit detects write errors.
In normal Write mode, the WUS output is low; in the conditions listed below, it is high.
• Head inputs is open (under the condition which. RH=∞ and Write data frequency is ≤ 10 MHz)
• Head input is shorted to GND or VCC.
• Write data frequency is abnormally low.
• No write current.
• In read mode.
• Supply voltage is abnormal (see power supply ON/OFF detection).
Power supply ON/OFF detection
This circuit monitors VCC to detect erroneous Writes. The error status is established when VCC falls below the
threshold voltage (VTH) of the power supply ON/OFF detector, in which case the recording and playback
functions are prohibited. When VCC rises above, VTH, the prohibition of these functions is released.
HS0
HS1
Head
L
L
0, 1
H
L
0, 1, 2, 3
L
H
2, 3
H
H
0, 1, 2, 3
Table 3. Head selection in Servo Write mode
—13—
CXA3510N
Application Circuit
1µ
PULSE
DETECTOR
RWC
3.3k
5.1k
20
19
18
17
16
15
14
13
12
11
1
2
3
4
5
6
7
8
9
10
LH
LH
LH
LH
1µH
1µH
1µH
1µH
5V
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.
—14—
CXA3510N
Notes on operation
• This device handles high frequency and high gain signals. Please note the following;
♦ Connect VCC decoupling capacitor of approximately 1000 pF near the device.
♦ Make the GND area as large as possible.
• When using as 2-channel, short-circuit the X and Y sides of unused head pins or leave them open.
• The WC pin is a constant voltage pin. When noise affects this pin, it creates noise in Write current.
Therefore, locate RWC as close to the device as possible.
• Write unsafe detection circuit
This circuit uses the voltage waveforms of the head pins for detection.
Wave form of write data
Voltage waveform
of head pins (HX, HY)
VFB
VTH=1.4V
VTH
GND
♦ VFB must be more than 2 V. When VFB < 2 V, it is possible that Write unsafe detection maximum
frequency becomes more than 1 MHz.
♦ The normal operating area of write unsafe detection circuit is changed by head inductance, head DC
resistance, write current and other.
—15—
CXA3510N
Application Notes
Use the following characteristics for reference.
VCC=5 V, Ta=25 °C
Item
Symbol
Differential output capacitance
Differential output resistance
Differential input capacitance
Read mode Differential input resistance
Output resistance
Unselected head differential current in Write
mode
CO
RO
CI
RI
RRD
Write current symmetry
TAS∗
Write mode
Conditions
Between head input pins
Between head input pins
f=5 MHz
RDX or RDY, f=5 MHz
LH=1 µH, RH=30 Ω
IW=15 mA
LH=0 µH, RH=0 Ω
IW=15 mA
IUS
Min. Typ. Max.
Unit
4.5
6
260 360 470
6
10
650 1500 3000
50
pF
Ω
pF
Ω
Ω
0.2 mAp-p
–0.5
0.5
ns
∗TAS=T1–T2
IWX+IWY
50%
50%
T1
50%
T2
WC
Setting of Write current
Write current can be set with resistor RWC (kΩ) at Pin 18.
IW=K/RWC (mA) Refer to Fig. 5.
RWC
Fig.6 Write current setting constant vs. Write current
Fig.5 Write current vs. RWC
55
Write current setting constant K
20
IW -Write current (mA)
18
10
5
52.5
K=RWC ·IW
50
47.5
45
2
5
10
15
4
6
8
10
12
Write Current IW (mA)
RWC (kΩ)
—16—
14
16
CXA3510N
Normalized write current
vs. Supply voltage
Normalized write current
vs. Ambient temperature
Ta=25°C
RWC=3.3kΩ
1.02
1
0.96
0.96
5
6
–25
0
25
75
50
Supply voltage VCC [V]
Ambient temperature Ta [°C]
Normalized read amplifier voltage tgain
vs. Supply voltage
Normalized read amplifier voltage gain
vs. Ambient temperature
Ta=25°C
1.02
1
0.98
VCC=5V
1.04
AV/AV (Ta=25°C)
AV/AV (VCC=5V)
1
0.98
1.04
0.96
1.02
1
0.98
0.96
4
5
6
–25
Supply voltage VCC [V]
4.2
OFF → ON
4
ON →OFF
3.8
3.6
–25
0
25
50
0
25
50
Ambient temperature Ta [°C]
Power supply ON/OFF detector threshold
voltage vs. Ambient temperature
Power supply ON/OFF Detector
Threshold Voltage [V]
1.02
0.98
4
VCC=5V
RWC=3.3kΩ
1.04
IW/IW (Ta=25°C)
IW/IW (VCC=5V)
1.04
75
Ambient temperature Ta [°C]
—17—
75
CXA3510N
Package Outline
Unit : mm
20PIN SSOP (PLASTIC)
+ 0.2
1.25 – 0.1
∗6.5 ± 0.1
0.1
11
20
1
6.4 ± 0.2
∗4.4 ± 0.1
A
10
0.65
b
(0.15)
(0.22)
0.5 ± 0.2
0.1 ± 0.1
DETAIL B : SOLDER
b=0.22 ± 0.03
+ 0.03
0.15 – 0.01
+ 0.1
b=0.22 – 0.05
+ 0.05
0.15 – 0.02
0.13 M
DETAIL B : PALLADIUM
NOTE: Dimension “∗” does not include mold protrusion.
0° to 10°
PACKAGE STRUCTURE
DETAIL A
PACKAGE MATERIAL
EPOXY RESIN
SOLDER / PALLADIUM
PLATING
SONY CODE
SSOP-20P-L01
LEAD TREATMENT
EIAJ CODE
SSOP020-P-0044
LEAD MATERIAL
42/COPPER ALLOY
PACKAGE MASS
0.1g
JEDEC CODE
NOTE : PALLADIUM PLATING
This product uses PdPPF (Palladium Pre-Plated Lead Frame).
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