HA13568AT Hitachi Semiconductor, HA13568AT Datasheet - Page 12

• Manufacturer Part Number: HA13568AT
• Description: CD-ROM Combo Driver
• Manufacturer: Hitachi Semiconductor

HA13568AT
External Components (cont)
Parts No.
Ct1
Ct2
Ct3
Q1
Note:
12
1. The output current maximum value Iospnmax of SPN driver is controlled according to the
2. The maximum duty Dmax of SLD driver output is controlled according to the following equation.
3. The CLK oscillation frequency is determined by the following equation.
4. The Ct2 for start-up oscillation is determined by the following equation.
However,
Where, Vrt
Since Vrt
Where, Vrt
Where, J
following equation. However, Vspncl is the current limiter reference voltage. (See the electrical
characteristics)
fclk =
fclk =
Iospnmax =
Dmax =
Rt = Rt1 + Rt2,
Tc2 =
Ct2 =
Reccomended
Value
150 pF
0.033 F
470 pF
8 Ct1 Rt Vct1
8 Ct1 Rt Vct1
8 Rt (Vhct2
1
6
Vlct3 : CT3 pin low voltage ( 1.3 V)
Vhct3 : CT3 pin high voltage ( 3.3 V)
P
Kt
Vhct2 : CT2 pin high voltage ( 3.3 V)
Vlct2 : CT2 pin low voltage ( 1.3 V)
Vhct3
Vct1 : CT1 pin voltage amplitude ( 1 V)
Vhct3, Dmax is not limited at 100% when Rt1 = 0 .
Vrt
Vrt
P Kt Ispnmax
Tc2 Vrt
Vspncl
Vrt
Rnf
: RT pin voltage (See the electrical characteristics)
: RT pin voltage (See the electrical characteristics)
: Spindle motor inertia (kg · cm · S
: Number of spindle motor poles (Total number of S poles and N poles)
: Spindle motor torque constant (kg · cm / A)
Vlct3
Rt2
J
Rt
Reccomended
Range
Vlct2)
120 pF
390 pF
Rt2
Rt
Vlct3
Vrt
Vlct3
Vrt
Purpose
Time constant for CLK oscillation. Use a
capacitor with good temperature characteristics.
Time constant for start-up oscillation. Use a
capacitor with good temperature characteristics.
PWM carrier oscillation time constant
Transistor for voltage regulator
100 (%)
2
)
Note
3
4
5