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Structure
Product Name
:
:
Silicon Monolithic Integrated Circuit
Power Driver for DVD-RAMs
Device Name
:
BA5955FP
Features
:
•
•
•
•
•
2-ch current feedback-type BTL driver
Use of an HSOP25PIN power package allows downsizing of the set.
A wide dynamic range
A built-in thermal shutdown circuit installed.
The pre stage (PRE part) and the output stage (POW part) are separated to
achieve an efficient drive.
• A built-in standby function installed.
{ ABSOLUTE MAXIMUM RATINGS (Ta=25°C)
Parameter
Symbol
Power Supply Voltage
Vcc
Power Dissipation
Pd
Maximum Output
Iomax
Current
Operating Temperature
Topr
Range
Storage Temperature
Tstg
Range
Limits
18
1.45*1
Unit
Ｖ
W
1*2
A
-35 to 85
°C
-55 to 150
°C
*1 When mounted on the glass/epoxy board with the size: 70 mm×70 mm, the thickness: 1.6 mm, and
the rate of copper foil occupancy area: 3% or less.
Over Ta=25°C, derating at the rate of 11.6mW/°C.
*2 The power dissipation should be specified within the ASO range.
{ OPERATING CONDITIONS
Parameter
Pre-stage Power Supply
Voltage
Output-stage Power
Supply Voltage
Symbol
Limits
Unit
PreVcc
PowVcc+3 to 14
V
PowVcc
4.5 to 11
V
This product has not been checked for the strategic materials (or service) defined in the Foreign
Exchange and Foreign Trade Control Low of Japan so that a verification work is required before
exporting it.
Not designed for radiation resistance.
REV. A
2/5
{ ELECTRIC CHARACTERISTICS (Ta=25°C, PreVcc=12V , PowVcc=5V, Vc=2V, RL=6Ω+150uH,
Rd=0.5Ω, unless otherwise noted.)
Parameter
Standby Consumption
Current
Quiescent
Consumption Current
Output Offset Current
Maximum Output
Amplitude 1
Maximum Output
Amplitude 2
Transfer Gain
Symbol
MIN.
TYP.
MAX.
Unit
IST
-
0.1
1
mA
IQpre
-
21
32
mA
Ioof
-6
-
6
mA
VOM1
3.6
3.9
-
V
VOM2
5.8
6.1
-
V
Gm
0.9
1
1.1
A/V
STBY ON Voltage
VSON
-
-
0.5
V
STBY OFF Voltage
VSOFF
2
-
-
V
1.9
2.0
2.1
V
5.0
6.0
7.0
dB
1.0
-
-
mA
1.0
-
-
mA
SRdet
-
1
-
V/µs
GBW
-
10
-
MHz
VRSTOFF
2.8
-
-
V
VRSTON
-
-
0.5
V
<Current Detection Amplifier>
Output Voltage (at no
Vodet
signal)
Closed Circuit Voltage
Gvdet
Gain
Output Driving Current
ISIdet
Sink
Output Driving Current
ISOdet
Source
Slew Rate
Voltage Gain
Bandwidth Product
<Reset>
Output Voltage in
non-operation
Output Voltage in
operation
Condition
At standby
When POWVcc= 8V
VIN= ±0.2V
100KHz square wave 2Vp-p
output
3.3V PULL UP with 10KΩ
attached
3.3V PULL UP with 10KΩ
attached
{ OUTLINE DIMENSIONS, SYMBOLS
Product Number
(UNIT: mm)
REV. A
3/5
{ APPLICATION CIRCUIT DIAGRAM
Focus coil
0.5Ω
μ-COM
A/D
FOCUS
12V
5V
25
24
23
22
21
20
19
LEVEL
SHIFT
PreVcc
18
17
16
15
14
PowVcc
V/I
PreVcc/Vc
DETECTER
T.S.D.
RESET OUT
V/I
LEVEL
SHIFT
Vc
1
2
3
VC
TRACKING
4
5
6
7
8
μ-COM
A/D
PowVcc
STBY
L:STBY
9
10
11
12
13
STAND-BY
10K
Tracking coil
0.5Ω
T.S.D: (Thermal shutdown)
Resistance unit: [Ω]
{ PIN Description
No.
Pin Name
1
Vc
2
IN1
3
FIL1
4
EOUT1
5
DETOUT1
6
DETIN1P
7
GND
8
RESET
Description
No.
Pin Name
Reference input for input signal
25
PreVcc
CH1 input
24
IN2
Description
Pre stage power supply terminal
CH2 input
Error amp phase compensation
external terminal 1
CH1 error amp output
23
FIL2
22
EOUT2
CH1 current detection amp output
21
DETOUT2
CH2 current detection amp output
20
DETIN2P
CH2 current detection amp
non-inverted input
19
GND
CH1 current detection amp
non-inverted input
Substrate GND
Reset output
Error amp phase compensation
external terminal 2
CH2 error amp output
Substrate GND
11
OUT1M
CH1 current detection amp inverted
input
CH1 negative output
16
OUT2M
Output stage power supply
terminal
CH2 current detection amp
inverted input
CH2 negative output
12
OUT1P
CH1 positive output
15
OUT2P
CH2 positive output
13
OUT1P
CH1 positive output
14
OUT2P
CH2 positive output
9
STBY
10
DETIN1M
Standby input
18
PowVcc
17
DETIN2M
REV. A
4/5
{ CAUTIONS ON USE
(1) The BA5955FP incorporates a TSD circuit (overheat protection circuit) and a reset circuit. When the
chip temperature has reached 175℃ (typ.), the output current will be muted while the reset output will
become ‘L’ and, when the chip temperature has dropped to 150℃ (typ.), the mute function will be reset
while the reset output will be ‘H.’ The reset output also becomes ‘L’ in the standby state.
(2) When the power supply voltage (PreVcc) has dropped to 3.8V (typ.) or less, the output current will be
muted while the reset output will become ‘L’ and, when PreVcc has recovered to 4.0V (typ.), the driver
part circuit will be initiated to set the reset output to ‘H.’
(3) When the reference input (Vc) voltage has dropped to 0.8V (typ.) or less, the output current will be
muted while the reset output will become ‘L.’
Under conditions of normal use, it should be 1.2V (typ.) or above.
(4) Thermal shutdown or a drop of reference voltage or power supply voltage will activate the mute
function, where only the driver part can be muted. While muting, the voltage at the output terminal will
equal to the internal reference voltage (approximately PowVcc/2).
(5) Connecting a capacitive load to the OP-AMP output results in a phase margin reduction of the amp and
may cause an oscillation or a peak. When connecting a capacitive load, a resistance must be
inserted in series between the output and the capacitive load. And after careful consideration of the
frequency characteristics, the device should be used within the range where no problem is found in
actual use.
(6) A radiating fin must be connected to the external GND.
(7) Short-circuits between output pin-VCC, output pin-GND, or output terminals (load short) must be
avoided.
Mounting the ICs in improper directions may damage them or produce smoke.
(8) About absolute maximum ratings
Exceeding the absolute maximum ratings, such as the applied voltage or the operating temperature
range, may cause permanent device damage. As these cases cannot be limited to the broken short
mode or the open mode, if a special mode where the absolute maximum ratings may be exceeded is
assumed, it is recommended to take mechanical safety measures such as attaching fuses.
(9) About power supply lines
As a measure against the back current regenerated by a counter electromotive force of the motor, a
capacitor to be used as a regenerated-current path can be installed between the power supply and
GND and its capacitance value should be determined after careful check that any problems, for
example, a leak capacitance of the electrolytic capacitor at low temperature, are not found in various
characteristics.
(10) About GND potential
The electric potential of the GND terminal must be kept lowest in the circuitry at any operation states.
(11) About thermal design
With consideration of the power dissipation (Pd) under conditions of actual use, a thermal design
provided with an enough margin should be done.
(12) About operations in a strong electric field
When used in a strong electric field, note that a malfunction may occur.
(13) ASO
When using this IC, the output Tr must be set not to exceed the values specified in the absolute
maximum ratings and ASO.
(14) Thermal shutdown circuit
This IC incorporates a thermal shutdown circuit (TSD circuit). When the chip temperature reaches the
value shown below, the coil output to the motor will be set to open.
The thermal shutdown circuit is designed only to shut off the IC from a thermal runaway and not
intended to protect or guarantee the entire IC functions.
Therefore, users cannot assume that the TSD circuit once activated can be used continuously in the
subsequent operations.
TSD ON Temperature
[°C] (typ.)
175
Hysteresis Temperature
[°C] (typ.)
25
REV. A
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(15) About earth wiring patterns
When a small signal GND and a large current GND are provided, it is recommended that the large
current GND pattern and the small signal GND pattern should be separated and grounded at a single
point of the reference point of the set in order to prevent the voltage of the small signal GND from being
affected by a voltage change caused by the resistance of the pattern wiring and the large current.
Make sure that the GND wiring patterns of the external components will not change, too.
(16) This IC is a monolithic IC which has a P+ isolations and P substrate to isolate elements each other.
This P layer and an N layer in each element form a PN junction to construct various parasitic elements.
Due to the IC structure, the parasitic elements are inevitably created by the potential relationship.
Activation of the parasitic elements can cause interference between circuits and may result in a
malfunction or, consequently, a fatal damage. Therefore, make sure that the IC must not be used
under conditions that may activate the parasitic elements, for example, applying the lower voltage than
the ground level (GND, P substrate) to the input terminals.
In addition, do not apply the voltage to input terminals without applying the power supply voltage to the
IC. Also while applying the power supply voltage, the voltage of each input terminal must not be over
the power supply voltage, or within the guaranteed values in the electric characteristics.
<Supplemental Remarks>
Current feedback driver
The transfer gain (output current/input current) can be determined by the following equation:
gm =
1
(A/V)
2 Rd
Rd = Resistance for current detection (Ω)
REV. A
Appendix
Notes
No technical content pages of this document may be reproduced in any form or transmitted by any
means without prior permission of ROHM CO.,LTD.
The contents described herein are subject to change without notice. The specifications for the
product described in this document are for reference only. Upon actual use, therefore, please request
that specifications to be separately delivered.
Application circuit diagrams and circuit constants contained herein are shown as examples of standard
use and operation. Please pay careful attention to the peripheral conditions when designing circuits
and deciding upon circuit constants in the set.
Any data, including, but not limited to application circuit diagrams information, described herein
are intended only as illustrations of such devices and not as the specifications for such devices. ROHM
CO.,LTD. disclaims any warranty that any use of such devices shall be free from infringement of any
third party's intellectual property rights or other proprietary rights, and further, assumes no liability of
whatsoever nature in the event of any such infringement, or arising from or connected with or related
to the use of such devices.
Upon the sale of any such devices, other than for buyer's right to use such devices itself, resell or
otherwise dispose of the same, no express or implied right or license to practice or commercially
exploit any intellectual property rights or other proprietary rights owned or controlled by
ROHM CO., LTD. is granted to any such buyer.
Products listed in this document are no antiradiation design.
The products listed in this document are designed to be used with ordinary electronic equipment or devices
(such as audio visual equipment, office-automation equipment, communications devices, electrical
appliances and electronic toys).
Should you intend to use these products with equipment or devices which require an extremely high level
of reliability and the malfunction of which would directly endanger human life (such as medical
instruments, transportation equipment, aerospace machinery, nuclear-reactor controllers, fuel controllers
and other safety devices), please be sure to consult with our sales representative in advance.
It is our top priority to supply products with the utmost quality and reliability. However, there is always a chance
of failure due to unexpected factors. Therefore, please take into account the derating characteristics and allow
for sufficient safety features, such as extra margin, anti-flammability, and fail-safe measures when designing in
order to prevent possible accidents that may result in bodily harm or fire caused by component failure. ROHM
cannot be held responsible for any damages arising from the use of the products under conditions out of the
range of the specifications or due to non-compliance with the NOTES specified in this catalog.
Thank you for your accessing to ROHM product informations.
More detail product informations and catalogs are available, please contact your nearest sales office.
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Appendix1-Rev2.0