Philips TDA5147K Datasheet

INTEGRATED CIRCUITS

DATA SH EET

TDA5147K

12 V Voice Coil Motor (VCM) driver and spindle motor drive combination chip

Product speciﬁcation File under Integrated Circuits, IC11

1996 Jul 26

Philips Semiconductors Product speciﬁcation

12 V Voice Coil Motor (VCM) driver and spindle motor drive combination chip

FEATURES Spindle motor driver

• Internal 1 A peak current power drivers

• Low R

drivers

• Induction sense start-up option

• External current sense resistor

• Soft switching on both upper and lower drivers

• Programmable linear or PWM spindle mode

• Provide spindle active dynamic braking mode.

Voice coil motor driver

• 0.8 Amp VCM power driver

• Maximum of 1 V drop across the power driver at 0.8 A

• External current sense resistor, with sense amplifier

• External current control loop compensation

• 15 kHz (typ.) VCM current control loop bandwidth

• Three mode operation: enable VCM, retract, and

disable.

Power monitor and retract circuit

• +5 and +12 V power monitor threshold accuracy ±2%

• Hysteresis on both power monitor comparators

• Precision internal voltage generator ±2%

• Buffered reference voltage output pin

1 Ω max total for high, low and isolation

ds(on)

TDA5147K

• Retract circuit operates down to 2 V

• Internal thermal sense circuitry with an over temperature

shut down option

• Internal boost voltage generator

• Sleep mode.

APPLICATIONS

• Hard disk drive for PC products.

GENERAL DESCRIPTION

The TDA5147K is an ASIC combination chip that includes the following functions; spindle motor drive, voice coil motor drive, retract, and power-on. The circuit is contained in a 52-pin PLCC package.

The TDA5147K (see Fig.1) is controlled by a custom digital ASIC. The custom ASIC provides the necessary commutation sequences for the spindle drivers via the SCNTL1, SCNTL2 and SCNTL3 inputs. Spindle speed is monitored by comparator outputs SENU, SENV and SENWIS. Motor speed control is accomplished by a PWM signal (input at the SIPWM pin).

Control of the VCM circuits is via the V input signals. These two inputs provide control of the coil current. The V

output signal can be used to monitor

ISENSE2

the voice coil current.

IPWMH

and V

IPWML

QUICK REFERENCE DATA

SYMBOL PARAMETER MIN. TYP. MAX. UNIT

Supply voltage

V V

CCA1 CCA2

analog supply voltage 1 4.5 5.0 5.5 V analog supply voltage 2 10.8 12.0 13.2 V

Drivers

spin(max)

VCM(max)

maximum spindle current − 1 − A maximum voice coil motor current − 0.8 − A

ORDERING INFORMATION

TYPE

NUMBER

NAME DESCRIPTION VERSION

PACKAGE

TDA5147K PLCC52 plastic leaded chip carrier; 52 leads SOT238-2

1996 Jul 26 2

Philips Semiconductors Product speciﬁcation

12 V Voice Coil Motor (VCM) driver and spindle motor drive combination chip

BLOCK DIAGRAMS

handbook, full pagewidth

POR

PCNTL

IPWMH

IPWML

DIGITAL CIRCUIT

ISENS2

SCNTL1 to 3

SENU, SENV, SENWIS SIPWM

TDA5147K

POWER-ON RESET

PARK

VOICE COIL

MOTOR DRIVE

SPINDLE

TDA5147K

ACTUATORS

MBH018

Overview No external power drivers; dynamic braking for non-power down situations; 1 A spindle current; 0.8A VCM power driver; full-wave spindle mode,

POR monitors for both 5 and 12 V supplies; auto-park in the event of power-down.

Fig.1 System block diagram.

1996 Jul 26 3

Philips Semiconductors Product speciﬁcation

12 V Voice Coil Motor (VCM) driver and spindle motor drive combination chip

handbook, full pagewidth

BSTFLT

SCNTL2

SCNTL3

10SCNTL1

3SMODE1

23SCOMP

DECODER

CCA1

25 21

UPPER

BOOSTER

LOGIC

CCA1

BSTCP2BSTCP1

U.H U.H

V.H V.L

W.H W.L

brake disable

COMP

PWM/LIN

CCS

to the VCM output stages

comp

THERMAL

SWITCH

set

sense

control

amplifier

SPWMTC

PWM/LIN

PWM

U.H

U.L

V.H

V.L

W.H

W.L

DRIVER

disable

brake

disable

brake

disable

brake

from POR block

CCS

TDA5147K

SHPWR3

SHPWR2

SDRVU

SHPWR1

clamp

SDRVV

SDRVW

13 V

sense

CCS

set

COMP

34 PGND150V

TDA5147K

COMP

CCA2

SISENL 32 SISENH 31

30SIPWM

26SPWMFLT

PWM

DECODER

FILTER

AMP

ref

Fig.2 Block diagram of spindle motor drivers.

1996 Jul 26 4

SISINK1, SISINK2

COMP

multiplexer

SISINK227SISINK145PGND2

SDRVU

SDRVV

SDRUW

18 17

MBH024

SDRVN

SENV SENU SENWIS

Philips Semiconductors Product speciﬁcation

12 V Voice Coil Motor (VCM) driver and spindle motor drive combination chip

handbook, full pagewidth

CCS

POR12

ADJ

CCA2

CCAI

CCV

UNDER

VOLTAGE

GENERATOR

ref

1339

POR

PWM

DETECTOR

to spindle

section

POR 5

disable

PCNTL

park

autopark

ref(o)

SHPWR

PARK

CICUITRY

POWER

RET 22

ADJ

SDRU

TDA5147K

CMN

POR5

IPWML

IPWMH

ADJ

ref(o)

ref(i)

46 47

PWM

DECODER

AGND1

5228

AGND2

ref(o)

48 V

FLTINP

TDA5147K

ref(o)

CCA2

FLTOUT

3349 V

CMINP

POWER

POWER AMPLIFIERS

SENSE

ref(o)

41 44 V

ISEN2

SENSE

ref(o)

ISEN1

42VCMP

ISENL

40VISENH

MBH023

Fig.3 Block diagram of voice coil motor driver.

1996 Jul 26 5

Philips Semiconductors Product speciﬁcation

12 V Voice Coil Motor (VCM) driver and spindle motor drive combination chip

PINNING

SYMBOL PIN I/O DESCRIPTION

CCA1

SDRVW 2 O phase 3 output for spindle motor SMODE1 3 I 3-state level input for spindle mode C

POR

POR 5 O power-on reset digital output (active LOW) POR12 POR5

ADJ

SENWIS 8 O digital output of back EMF sense 3/inductive sense SISINK2 9 − connection 2 to the sense resistor SCNTL1 10 I digital input 1 for spindle decoder SCNTL2 11 I digital input 2 for spindle decoder SDRVV 12 O phase 2 output for spindle motor V

CCS

SCNTL3 14 I digital input 3 for spindle decoder SPWMTC 15 O capacitor for spindle low side PWM time off SDRVN 16 O centre TAP connection to spindle motor SENU 17 O digital output of back EMF sense 1 SENV 18 O digital output of back EMF sense 2 SHPWR3 19 O capacitor 3 for PARK supply voltage BSTFLT 20 O booster ﬁlter output BSTCP2 21 O booster capacitor 2 output RET

ADJ

SCOMP 23 O control ampliﬁer pole adjustment SDRVU 24 O phase 1 output for spindle motor BSTCP1 25 O booster capacitor 1 output SPWMFLT 26 O capacitor for spindle PWM ﬁlter SISINK1 27 − connection 1 to the sense resistor AGND1 28 − analog ground 1 SHPWR1 29 O capacitor 1 for PARK supply voltage SIPWM 30 I digital PWM input for spindle current SISENH 31 O sense resistor for spindle current SISENL 32 O isolated ground connection for spindle sense ampliﬁer V

CMINP

PGND1 34 − power ground of VCM driver V

PCNTL

CMN

ref(o)

ref(i)

CCV

ISENH

1 − analog supply voltage 1 (+5 V)

4 I/O power-on reset delay capacitor

6 O adjustment of POR threshold (for +12 V) 7 O adjustment of POR threshold (for +5 V)

13 − power supply of spindle motor drivers (+12 V)

22 I/O retract voltage adjustment pin

33 I closed loop voltage compensation of VCM

35 I PARK enable 3-state voltage level input 36 O negative output voltage of H-bridge 37 O reference voltage output for external ADC 38 I reference voltage input for the 2nd sense ampliﬁer 39 − power supply of VCM driver (+12 V) 40 I positive input voltage of sense resistor ampliﬁer

TDA5147K

1996 Jul 26 6

Philips Semiconductors Product speciﬁcation

12 V Voice Coil Motor (VCM) driver and spindle motor drive combination chip

SYMBOL PIN I/O DESCRIPTION

ISENS2

CMP

ISENL

ISENS1

PGND2 45 − power ground 2 of voice coil motor driver V

IPWML

IPWMH

FLTINP

FLTOUT

CCA2

SHPWR2 51 O capacitor for PARK supply voltage AGND2 52 − analog ground 2

41 O voltage output 2 of sense resistor ampliﬁer 42 O positive output voltage of H-bridge 43 I negative input voltage of sense resistor ampliﬁer 44 O voltage output 1 of sense resistor ampliﬁer

46 I PWM input voltage (LSB) 47 I PWM input voltage (MSB) 48 O voice coil motor PWM ﬁlter capacitor 49 O PWM ﬁlter output voltage 50 − analog supply voltage 2 (+12 V)

TDA5147K

handbook, full pagewidth

SDRVW

SMODE1

POR12

POR5

SENWIS SISINK2 SCNTL1 SCNTL2

SDRVV

CCA1

POR POR

ADJ ADJ

CCS

CCA2VFLTOUTVFLTINPVIPWMHVIPWMLVISENS1

SHPWR2

AGND2

47 1 2 3 4 5 6 7 8 9

10 11 12 13

SCNTL3

SDRVN

SPWMTC

SENU

TDA5147K

SENV

SHPWR3

PGND2

BSTFLT

BSTCP2

ADJ

RET

ISENLVCMP

V 43

SCOMP

SDRVU

BSTCP1

ISENS2VISENH

39 38 37 36 35 34 33 32 31 30 29 28 27

MBH017

SPWMFLT

CCV

ref(i)

ref(o)

CMN

PCNTL

PGND1 V

CMINP

SISENL SISENH SIPWM SHPWR1 AGND1 SISINK1

Fig.4 Pinning configuration.

1996 Jul 26 7

Philips Semiconductors Product speciﬁcation

12 V Voice Coil Motor (VCM) driver and spindle motor drive combination chip

FUNCTIONAL DESCRIPTION Spindle drivers

The spindle section contains both the low and high side drivers (configured as H bridges) for a three-phase DC brushless motor. Back EMF (BEMF) sensing of the commutation rate needs to be output to an external digital ASIC circuit. This digital circuit also provides the input commutation control. Consequently, all speed control, start-up routine and commutation control will be generated by the digital circuit.

The SIPWM signal from the digital circuit is used to control the spindle current. This PWM signal is internally filtered. The output of this filter is duty factor dependent only. The filter characteristics is that of a 1-pole low-pass filter, with the pole location being controlled by the external capacitor connected to pin SPWMFLT.

Dynamic braking is possible only during non power-down situations and must be initiated by the digital circuit.

SMODE1

TDA5147K

to obtain high start-up torque. The purpose of the PWM mode is to drive the low drivers into saturation (saturation reduces the power dissipation in the TDA5147K during start-up).

When the spindle current reaches the programmed set current (SIPWM) value, a one-shot is fired. The output of the one-shot remains high for the programmed off-time

) set by the capacitor/resistor network at the SPWMTC

off

pin. The one-shot is not retriggerable for approximately 10% of the off-time, this gives a minimum of (10% t time-on. During the off-time, the lower spindle output drivers are switched off. The on-time of the drivers is not fixed but is determined by the charging time of the coil current to reach the program set current.

The turn-off time is calculated by the equation: t

=R×C

off

Where R = 68 kΩ and C = 220 pF, t

ln(2)

= 10.4 µs.

off

The minimum on-time can be calculated by the equation:

--------

)

off

A 3-state level mode line (SMODE1) has been included to allow for;

1. An induction sensing algorithm in pre-start-up (V

2. PWM control during start-up (0.5V

CCA1

3. Linear control (0 V).

ENSING MODE

The induction sensing mode is used for two purposes. Firstly one of the BEMF sensor outputs (SENWIS) will be shared with the voltage comparator that is used for the induction sensing function. Prior to start-up each phase can be excited for a short period of time. The current from each coil can be monitored via the multiplexed output (SENWIS). By comparing the rise times of each phase the rotor position can be determined.

Secondly, in situations where the spindle motor requires more current to spin-up, this mode is used with the exception that the output SENWIS is ignored. Since, in the induction sense mode, the output drivers are operated in saturation mode, the motor current is limited only by the power supply. This condition of induction sense mode can be used to overcome the head friction and must be used only when needed.

PWM M

ODE

INEAR MODE

L The linear mode is used when the motor is near to its

intended speed. It can also be used at start-up, but higher power dissipation will occur. In the linear mode the linear drivers are controlled by a sensing amplifier. A Miller network is used to obtain soft switching on the lower drivers. This prevents large voltage spikes on the motor coils when the lower drivers are switching. The high drivers are switched into the linear (resistive) region.

The transconductance gain of the low driver current to filter voltage can be calculated as follows:



coil

--------------------------- V

SPWMFLT

SISENH



------

--------------------------- -



SPWMFLT

-----R

For a 100% duty factor at SIPWM, the nominal voltage at SPWMFLT = 1.74 V. The calculated coil current for a 100% duty factor (sense resistors R

coil

-----------

0.33

1.74 1.05 A=××=

-- 5

= 0.33 Ω) is:

Referencing to the duty factor, the coil current is:

coil

-----R

1.74

0% duty

××

--------------------100

-- 5

0.348()

-----R

A/V===

-- 5

0% duty

×== =

--------------------100

The PWM mode is normally used during the start-up phase. Maximum drive voltage is applied to the low drivers

1996 Jul 26 8

Philips Semiconductors Product speciﬁcation

12 V Voice Coil Motor (VCM) driver and

TDA5147K

spindle motor drive combination chip

The duty factor is arranged so that at 100%, the voltage SPWMFLT = 1.74 V and at a 5% duty factor SPWMFLT = 0 V. This is to ensure that at 0% duty factor the current will be zero (allowances for circuit tolerances).

The input decoder is driven by three lines which define the windings to be energized. The input decoder must then translate these lines to six lines to drive the six output drivers. The truth table is given in Table 1.

Table 1 Input decoder truth table

(1)

CONDITION SCNTL1 SCNTL2 SCNTL3 SDRVU

SDRVV

Disable LOW LOW LOW X X X Dynamic brake HIGH HIGH HIGH HIGH HIGH HIGH State 1 HIGH HIGH LOW LOW X HIGH State 2 HIGH LOW LOW X LOW HIGH State 3 HIGH LOW HIGH HIGH LOW X State 4 LOW LOW HIGH HIGH X LOW State 5 LOW HIGH HIGH X HIGH LOW State 6 LOW HIGH LOW LOW HIGH X Under voltage −−−XXX

Note

1. X = 3-state.

(1)

SDRVW

(1)

VCM driver

The VCM driver is a linear, class AB, H-bridge type power driver with all power devices internal to the chip. In addition to the power stage a sense resistor enables VCM current to be measured and brought out to a separate ADC via the V

pin. The reference voltage for the V

ISENS2

output is provided externally. The current level to the VCM is controlled via two PWM signals that are generated by the digital circuit. The input voltage at pin 47 (V

handbook, full pagewidth

PWM (MSD)

PWM (LSB)

LEVEL

CONVERTOR

LEVEL

CONVERTOR

IPWMH

ref

)

ATTENUATION

represents a weighting of 32 times more than the input voltage at pin 46 (V equal to 32 × duty factor (V

), thus the current command is

IPWML

IPWML+VIPWMH

). These PWM signals are filtered by an internal 3rd-order low-pass filter (Butterworth filter). The bandwidth of this low-pass filter is nominally 40 kHz (less than 2 degrees lag at 500 Hz), but the real pole may be adjustable by an external capacitor. The analog output of the filter depends on the duty factor of the PWM signal and not on the logic level.

32 : 1

SUM

UNITY

GAIN

LOW-PASS

MBH019

analog output

Fig.5 Block diagram of the PWM filter.

1996 Jul 26 9

Philips Semiconductors Product speciﬁcation

12 V Voice Coil Motor (VCM) driver and spindle motor drive combination chip

PARK ENABLE A 3-state-level mode line (V

will:

1. Enable VCM drivers; V

2. Disable VCM drivers; 0.5V

3. PARK (soft retract the actuator); 0 V.

Enable VCM drivers

When the enable signal is HIGH, the VCM drivers are controlled by the two PWM inputs. The two digital signals convert the duty factor to a voltage level at V 100% duty factor the V above V

. At a 0% duty factor the V

ref(o)

FLTINP

approximately −1 V below V voltage level is equal to V

ref(o)

voltage is amplified, filtered and output at V voltage at V V

voltage, in conjunction with the sense resistor

FLTOUT

varies between ±2 V about V

FLTOUT

amplifier, drives the two VCM drivers as illustrated in Fig.8. The transconductance equation that governs the voltage

to I

coil

------- R1

is:

coil

–

Amps per Volt

×××=

-----R

from V

FLTINP

---------------------------------------------

-----------gain

FLTINPVref o()

In a typical application:

--------------------------------------------V

coil

–

FLTINPVref o()

-- 4

6.6 kΩ

-----------------10 kΩ

The transconductance is variable by selecting external resistors R2/R1 and sense resistors R

Disable VCM drivers

With the PARK enable signal at 0.5V the VCM drivers are disabled while the rest of the circuits remain enabled. A sleep mode is initiated when the spindle and VCM are disabled (this places the TDA5147K in its lowest power setting).

) has been included that

PCNTL

(normal).

CCA1

. At a

FLTOUT

voltage is approximately 1 V

voltage is

FLTINP

. At a 50% duty factor, the

ref(o)

(typical 4 V). The V

-----------------------------------------------------V

coil

FLTOUTVref o()

–()

× 1 Amp per Volt==

-----------

0.33

FLTOUT

FLTINP

. The

ref(o)

. The

TDA5147K

CTUATOR PARK

A Retracting the actuator can be accomplished by driving

LOW in conjunction with either the spindle is

PCNTL

turning or a brake voltage has been applied. An adjustable retract voltage of 1.2 V (max.) is applied between the V and V

outputs. The retract circuit obtains its retract

CMP

current from the spindle SDRVU phase. If the SDRVU phase is zero there will be no retract voltage.

The retract voltage is determined by two external resistors. One end is tied to V common point is tied to pin 22 (RET

and the other to ground. The

CMN

); see Fig.1 for

ADJ

additional information. The calculation of V

RETRACT

Where 0.65 is V

0.65

RETRACT

×=

at 25 °C ∆VBE/∆T=−2 mV/°C; 50 kΩ

is as follows:

1R2+



-----------------



--------------- 50 kΩ

can vary by ±30% It should be noted that R2 has to be less than 10 kΩ.

Power-on reset

The power-on reset circuit monitors the voltage levels of both the +5 V and the +12 V supply voltages as shown in Fig.6. The

POR (active LOW) logic line is set HIGH following a supply voltage rise above a specified voltage threshold plus a hysteresis, and delayed by a time, tC that

is controlled by an external capacitor. This

POR signal should remain HIGH until either the +5 or +12 V supplies drop below the voltage threshold, at which point the line should be asserted LOW. The tC timing is set by the following equation:

Where V

-----------------I

= 2.5 V and I is 12 µA (typ.).

A negative going pulse width of 5 µs on either the +5 or +12 V rail will provide a full output pulse. If another trigger pulse occurs before the output is completed a new output pulse will be originated. This implies the power-on reset circuit is a retriggerable one-shot with a maximum trigger pulse of 5 µs (see Fig.7).

CMN

POR

1996 Jul 26 10

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