HA13614FH Datasheet, PDF (17/26 Pages) Hitachi Semiconductor – Combo (Spindle & VCM) Driver

HA13614FH
Notes: 1. The operation threshold voltage of Vps or Vdd is determined by resistor R101, R102 or R107,
R108 as follows.
POR
(for Vdd)
12VGOOD
(for Vps)
Vdwn
Vup
Vps
• for Vps
Recovery
voltage
Vup(Vps) = (Vsd1 + Vhys3) ⋅
1+
R101
R102
[V]
(1)
Cut off
voltage
Vdwn(Vps) = Vsd1 ⋅
1+
R101
R102
[V]
(2)
where, Vsd1 : Operating voltage of the power monitor [V] (refer to Electrical Charasteristics)
Vhys3 : Hysteresis voltage of the power monitor [V] (refer to Electrical Charasteristics)
• for Vdd
Recovery
voltage
Vup(Vdd) = (Vsd1 + Vhys4) ⋅
1+
R107
R108
[V]
(1)’
Cut off
voltage
Vdwn(Vdd) = Vsd1 ⋅
1
+
R107
R108
[V]
(2)’
where, Vhys4 : Hysteresis voltage of the power monitor [V] (refer to Electrical Charasteristics)
2. The relation between PWMDAC input VIPWMH, VIPWML for VCM driver current control and VCM
driver input (VCMIN – VREF) is determined by following equation. (refer to below figure)
VCMIN − VREF =
6.4
6500
⋅ (64 ⋅ DPWMH + DPWML) − 3.2
(3)
where, VREF
DPWMH
DPWML
: Internal reference voltage [V] (refer to Electrical Charasteristics)
: Duty of input signal on terminal VIPWMH [%]
: Duty of input signal on terminal VIPWML [%]
VREF
VIPWMH
VIPWML
R1L ^R0
VREF
5.3V
R1H ^DACOUT R2
R1=R1L//R1H//R0 ^C1
=740Ω
R3
OP2IN(+) OPAmp.2
+
C2
C3 GND _R4
−
R5
OP2OUT
R5/R4=0.604
VCMIN
5.3V
VREF
to VCM driver
VCMIN
5.3±3.2V
3. The 3rd order LPF at next stage of PWMDAC is characterized by internal OP amp. and capacitor
C1, C2, C3 and resistor R2, R3. These components value are determined by following equations.
C1 =
1
2 ⋅ π ⋅ fc ⋅ R1
[F]
(4)
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