AN8387S Datasheet, PDF (6/6 Pages) Panasonic Semiconductor – 2-channel Linear Driver

AN8387S
ICs for CD/CD-ROM Player
IA = ^{|VIN –Vref |}
RIN+1kΩ
1) When VIN>Vref, the direction determining circuit operates
so that the following conditions are met.
SW.A : +
SW.B : ON
SW.C : OFF
2) When VIN<Vref, the direction determining circuit operates
so that the following conditions are met.
SW.A : –
SW.B : OFF
SW.C : ON
The output (V+–V–) between the pins18 and 17 has the
following relation with the input (VIN –Vref) between the
pins 2 and 4.
(V+ –V–) =
57.6kΩ
RIN+1kΩ
(VIN –Vref)
Therefore, the driver’s gain G will be as follows. (when the
motor load RL is 8.2Ω)
G=
(V+ –V–)
(VIN –Vref)
=
57.6kΩ
1kΩ + RIN
The output voltage V_ of the pin17 and V+ of the pin18 can
be limited by applying a voltage to the VLIM pin20.
For example, if a voltage of 3V is applied to the pin20
when VCC = 9V and RL = 8.2Ω, the maximum value of |V+
–V– | is limited within the following range.
2.25V ≤ |V+ –V– | ≤ 3V
When the pin20 is short-circuited to GND,
|V+ –V– | ≤ 130mV results regardless of an input error signal
(VIN).
If the pin20 is prepared to short-circuit to GND at power-on of
the set, it can be used to prevent operation error at power-on
of the motor or actuator.
When the pin20 is not used, short-circuit it to the pins1 and
10.
The pin3 is a PC pin. If a voltage of 2.8V or more is
applied to this pin, SW.B and SW.C are turned on, IA becomes
0mA, and the base current flows to the bases of Q3 and Q4
simultaneously to turn on Q3 and Q4. As a result, the
pins17 and 18 are almost short-circuited to P.GND.
This IC incorporates the thermal shutdown circuit. If
the chip temperature of the IC comes to about 160˚C,
both drivers of the two channels are turned off. (the output
pins17, 18, 14, and 13 are short-circuited to P.GND)
Similarly, if the applied voltage (Vref) of the Vref pin4
comes to 1V or less, both drivers of the two channels are
turned off.
• Driver Input/Output Characteristics
Input Offset (VIOF)
Output Offset (VOOF)
Dead Zone (|VDZ|)
Transfer Gain (+) (G+)
(+), (–) Transfer Gain Ratio (RG)
VCC = 9V
P.VCC = 9V
Vref = 4.5V
Output
V1, V2
0.25V
VIOF
B5
G–
B4
4.43V 4.45V
VOOF
B3
4.5V
4.55V
Input
4.57V VIN
B2
C– ^B1
|VDZ|
– 0.25V
• Characteristics Curve
PD –Ta
2000
1800
1600
1400
1200
1000
800
600
400
200
0
0
When Mounted to PCB : Material. Glass Epoxy PCB.
Size…5cm × 5cm × 0.8mm
θj– a=83.3˚C/W
20
40
60
80
100 120 140
Ambient Temperature Ta (˚C)
G+ =
B5–B4
20mV
, ^{G– =}
B2–B1
20mV
,
RG =
G+
G–