BETWEENTHE 2 MODES
CLASS ABOUTPUT DRIVERS
ZEROCROSSOVERDISTORSION
14 BIT DACDEFINEOUTPUT CURRENT
SELECTABLETRANSCONDUCTANCE
4 PROGRAMMABLEPARKING VOLTAGE
DYNAMICBRAKE
SPINDLEDRIVER
2.0ADRIVE CAPABILITY
0.8Ω TOTALBRIDGE IMPEDANCEAT 25°C
BEMF, INTERNAL OR EXTERNAL, PROC-
5V MONITORING WITH EXTERNAL SET
TRIP POINTSAND HYSTERESIS
POWERUP/DOWN SEQUENCING
LOW VOLTAGESENSE
BICMOS TECHNOLOGY
TQFP44 (10x10mm)
ORDERING NUMBER: L6275
3.3V INPUTLOGIC COMPATIBILITY
THERMAL SHUTDOWN AND PRETHERMAL
WARNING
SYSTEMCLOCK WATCHDOG
DESCRIPTION
The L6275 integratesinto a single chip both spindle and VCM controllers as well as power stages.
The device isdesigned for 12V disk drive application requiring up to 2.0A of spindle and 1.5A of
VCM peak currents.
A serial port with up to 25 MHz capabilityprovides
easy interface to the microprocessor. A register
controlled Frequency Locked Loop (FLL) allows
flexibility in setting the spindle speed. Integrated
BEMF processing, digital masking, digital delay,
and sequencingminimize the number of external
componentsrequired.
Power On Reset (POR)circuitry is included. Upon
detection of a low voltage condition, POR is asserted, the internal registers are reset, and spindle powercircuitry is tri-stated.The BEMF is rectified providing power for actuator retraction
followed bydynamicspindle braking.
The device is built in BICMOS technology allowing dense digital/analog circuitry to be combined
with a highpower DMOS outputstage.
April 1999
This is preliminaryinformation on a new product now in development. Details are subject to change without notice.
PIN DESCRIPTION(PinTypes: D = Digital,P = Power,A = Analog)
N.NameFunction
1FCOMOutput of the Spindle zero cross or Current Sense circuit.
2CTAPSpindle Central Tap used for differential BEMF sensing.
3PWM/SLEWRC network sets the Spindle Linear Slew Rateand PWM OFF-Time.
4OUT_CSpindle DMOS Half Bridge Output and Input C for BEMF sensing.
5I_SENSEInput to sense the voltage the SPINDLE Sense Resistor.
6R_SENSEOutput connection for the Motor Current Sense Resistor to ground.
7OUT_BSpindle DMOS Half BridgeOutput and Input B for BEMF sensing.
8GNDSpindle Ground (Substrate).
9R_SENSEOutput connection for the Motor Current Sense Resistor to ground.
10OUT_ASpindle DMOS Half Bridge Output and Input A for BEMF sensing.
11INDEXInput to allow Spindle to be locked to Index (servo) pulse.
12BRK_CAPStorage Capacitor for brake circuit. typically 5.9V.
13VDD+5V Power Supply for Spindle Power section.
14DGNDDigital Ground.
15SYS_CLKClock Frequency for system timers and counters.
16SDENSerial DataEnable. Active high input pin for the serial port enable.
17SDATASerial Port Data. Input/Output pin for serial data, 8bits of instruction/address followed by 8
bits of data. Open pin is at logic low as an input.
18SCLKSerial Port Data Clock. Positive edge triggered clock input for the serial data.
19VDDDigital/Analog power supply. +5V nominally.
20V12/2Reference Output for VCM control loop. Typically, half of the VCC except when parking.
21FLL_FILTERSpeed loop R/C compensation connection used for FLL mode operation.
22VCM_CALVCM loop offset voltage used forcalibration.
23CPExternal Main Charge Pump Capacitor, Typically, Vz+Vcc is about 17.8V
24CSExternal Charge Pump Capacitor.
25VDD+5V Power Supply for VCM Power section.
26VCM_A-VCM Power Amplifier negative output terminal.
27SENSE_IN+Non inverting Input of the Sense Amplifier for VCM block.
28VCM_GNDGround for VCM Power section.
29SENSE_IN-Inverting Input of the Sense Amplifier for VCM block.
30VCM_A+VCM Power Amplifier positive output terminal.
31VDD+5V Power Supply for VCM Power section.
32FLL_RESResistor for setting accurate bias current sources for the chip (62K required).
33SW1External ISOFET driver.
34PORBPower on Reset Output. Low signal indicates the failure of the supplies.
35TR_5VSet Point Input for 5V Supply Monitor ( 2Vthreshold, 100mV Hysteresis)
36POR_DELAYCapacitor connection to set the Power on Reset Delay (3V threshold, 2µA charging)
37SENSE_OUTOutput of the Sense Amplifier.
38ERROR_OUTOutput of the Error Amplifier.
39ERROR_INInverting Input of the Error Amplifier.
40CLK_MONWatchdogclock monitoring pin
41DACOutput of the VCM DAC.
42AGNDAnalog Ground. For bang gap voltage reference.
43VCC+12V Power Supply for Spindle Power section.
44SPN_COMPExternal RC network that defines the compensation of theSpindle Transconductance Loop
in Linear Mode.
L6275
3/17
L6275
ABSOLUTEMAXIMUM RATINGS
SymbolParameterValueUnit
V
CC
V
dd
V
in max
V
in min
SPINDLE I
VCM I
peak
P
(*)Maximum Total Power Dissipation≈ 1.7W
tot
T
stg,Tj
THERMAL DATA
SymbolParameterValueUnit
R
th j-case
R
th j-amb
(*) In typicalapplication with multilayer 120X120mm Printed Circuit Board
Maximum Supply voltage-0.5 to 14V
Maximum Logic supply-0.5 to 6V
Maximum digital input voltageVdd+0.3VV
Minimum digital input voltageGND - 0.3VV
Spindle peak sink/source output current2.1A
peak
VCM peak sink/source output current1.6A
Maximum Storage/Junction Temperature-40 to 150°C
Thermal Resistance Junction to Case≈ 20°C/W
(*)Thermal Resistance to Junctionto ambient
40°C/W
≈
RECOMMENDED OPERATINGCONDITIONS
SymbolParameterValueUnit
V
dd
T
amb
T
j
ELECTRICAL CHARACTERISTICS
Supply Voltage4.5 to 5.5V
Operating Ambient Temperature0 to 70°C
Junction Temperature0 to 125°C
Off State Leakage0 < Vfll_res , 3V-50+50nA
On State CurrentFLL_RES = 62k
ICP = ”1”
ICP = ”0”
V
RCP
Current Set VoltageFLL_RES = 62k
<1mA
O
Vdd/2
±
1.4V
0.5
0.8
0.850
0.650
1.600
1.150
160
320
80
160
0.45
0.74
= 100kΩ0.20.30.5V/µs
10
20
202840mVp-p
Ω
22
80
Ω
1.181.2251.25V
25
100
32
120
V
Ω
Ω
mV
mV
mV
mV
ms
ms
ms
ms
Ω
Ω
V/µs
V/µs
µA
A
µ
6/17
ELECTRICALCHARACTERISTICS (Continued)
SymbolParameterTest ConditionMin.Typ.Max.Unit
CURRENT SENSE AMPLIFIER
I
BIAS
AvVoltage Gain3.84.04.2V/V
dV
o/dt
SERIAL PORT
SymbolParameterMin.Typ.Max.Unit
T
SCK
T
CKL
T
CKH
T
SDENS
T
SDENH
T
DS
T
DH
T
SDENL
T
SDV
T
SDV
Input Bias Current2
Output Slew Rate20V/µs
SCLK Period40ns
SCLK low time15ns
SCLK high time15ns
Enable to SCLK35ns
SCLK to disable20ns
Data set-up time before rising edge SCLK10ns
Data Hold Time10ns
Minimum SDEN Low Time50ns
SCLK falling edge (A6) to SDATA valid on READ op.310ns
SCLK rising edge (D0-D7) to SDATA Transition onREAD op.535ns
L6275
A
µ
Figure 1. SerialPort Timing Information.
SDEN
SCLK
SDATA
SDEN
SCLK
SDATA
0A0A1
1st Byte2nd Byte
1A0A1
1st Byte2nd Byte
A6D0D1D2D7
SERIAL PORT WRITE TIMING
A6D0D1D2D7
SERIAL PORT READ TIMING
D98IN844
7/17
L6275
SERIAL PORTOPERATION
The serial port interface is a bi-directionalport for reading and writing programming data from/to the internal registers of this device. For data transfers SDEN* is brought high, serial data is presented at the
SDATA pin, and a serial clock is applied to the SCLK pin. After the SDEN* goes high , the first 16 pulses
applied to the SCLK pin will shift the data presented at the SDATA pin into an internal shift register on
the rising edge of each clock. An internal counterprevents more than 16 bits from being shifted into the
register. The data in the shift register is latched after the 16th SCLK pulse. If less than 16 clock pulses
are provided beforeSDEN* goes low,thedata transferis aborted.
All transfers are shifted into the serial port LSB first. The first byte of the transfer is for R/W and address
and instructioninformation.Thefirst bit is R/W instructionbit, 0 is for WRITE and 1 is for READ.
Following7 bitsare Address.
Figure 2. SerialPort Data Transfer Format.
SDEN
SDATA
INSTRUCTION, 1 BIT
ADDRESS, 7 BITS
DATA, 8 BITS
SCLK
D98IN845
INTERNALREGISTER DEFINITION
Reg:
Name:
Type:
Address:
BITLABELDESCRIPTION
0VDAC BIT8VCM DAC bit 8
1VDAC BIT9VCM DAC bit 9
2VDAC BIT10VCM DAC bit 10
3VDAC BIT11VCM DAC bit 11
4VDAC BIT12VCM DAC bit 12
5VDAC BIT13MSB resistor ladder of the14 bit VCM DAC
6PSM/LINEARSelects Voice Coil PSM or Linear Output Current Control. 1=PSM
7VCM_CALVCM calibration. 1 = Enables VCM control circuits and tristates
0
VCM DAC (High)Register
Write only
0Eh
0=Linear.
VCM power transistors.
8/17
L6275
INTERNALREGISTER DEFINITION
VCM DAC (High and Low)Registers
Bit 0 through 5 of the VCM DAC (High) Registers and bit 0 through 7 of the VCM DAC (Low) Registers
control the absolute value of the voice coil current. Bit is the sign bit, controlling the current direction. All
the 13 bits are part of a resistordividernetwork.
Note. Itis requiredto write on register 1 to make effectivechangeson register 0.
Reg:
Name:
Type:
Address:
BITLABELDESCRIPTION
0VDAC BIT0LSB resistor ladder of the 14 bit VCM DAC
1VDAC BIT1VCM DAC bit 1
2VDAC BIT2VCM DAC bit2
3VDAC BIT3VCM DAC bit3
4VDAC BIT4VCM DAC bit4
5VDAC BIT5VCM DAC bit5
6VDAC BIT6VCM DAC bit6
7VDAC BIT7VCM DAC bit7
Reg:
Name:
Type:
Address:
1
VCM DAC (Low) Registers
Write only
1Eh
2
Spindle ControlRegister
Write only
2Eh
BITLABELDESCRIPTION
0INCRE_SEQA 0 to 1 transition of this bit increments the spindle Sequencer.
1START_UP1 = Spindle Internal start up, 0 = Spindle External start up
2R_SEQReset Spindle sequencer. 1 = Reset sequencer to phase 1.
3RUN1 = Start Spindle ALIGN & GO, 0 = Reset Spindle control logic.
4SPIN_ENEnable Spindle section. 1 = Enable, 0 = Disable.
5MEC/ELECSpecifies electrical or mechanical cycle for Spindle FLL control.
6PWM/LINEARSelects Spindle PWM or Linear Output Current Control. 1 = PWM,
7EXT/INTExternal or internal Spindle loop feedback. 1 = external feedback
1=Electrical, 0 = Mechanical.
0=Linear.
via index pin.
9/17
L6275
INTERNALREGISTER DEFINITION
Reg:
Name:
Type:
Address:
BITLABELDESCRIPTION
0MASK_TIMESpindle BEMF Mask Time. 0 = 15 degree, 1 = 7.5 degree
1MIN2Control Spindle PWM on timeMin 1Min2Min.on Time
2MIN1011.4µs
38_12_POLESelects 8 or 12 pole motors.1 = 8 pole, 0 = 12 pole.
4SD3Spindle commutation delay MSB
5SD2Spindle commutation delay bit
6SD1Spindle commutation delay bit
7SD0Spindle commutation delay LSB
3
Spindle DelayRegister
Write only
3Eh
005.9µs
1012
115.21µs
s
µ
SPINDLEPHASE DELAY
SD3-0 set the phase delay from BEMF zero crossing to the next commutation.The30 theoreticaldegree
value can be changed to compensatefor switching and other delays that are always present. The delay
adjustmentrange is from 1.875 throughto 30 electricaldegreesin 1.875 degree increments.
Reg:
Name:
Type:
Address:
BITLABELDESCRIPTION
0C4Bit 4 of Spindle FLL Coarse Counter
1C5Bit 5 of Spindle FLL Coarse Counter
2C6Bit 6 of Spindle FLL Coarse Counter
3C7Bit 7 of Spindle FLL Coarse Counter
4C8Bit 8 of Spindle FLL Coarse Counter
5C9Bit 9 of Spindle FLL Coarse Counter
6C10Bit 10of Spindle FLL Coarse Counter
7C11MSB of Spindle FLL Coarse Counter
10/17
4
FLL Coarse Counter Register
Write only
4Eh
INTERNALREGISTER DEFINITION
L6275
Reg:
Name:
Type:
Address:
BITLABELDESCRIPTION
0F8Bit 8of Spindle FLL Fine Counter
1F9Bit 9of Spindle FLL Fine Counter
2F10MSB of Spindle FLL Fine Counter
3Unused. Set = 0
4C0LSB of Spindle FLL Coarse Counter
5C1Bit 1 of Spindle FLL Coarse Counter
6C2Bit 2 of Spindle FLL Coarse Counter
7C3Bit 3 of Spindle FLL Coarse Counter
Reg:
Name:
Type:
Address:
5
FLL Coarse/FineCounter Register
Write only
5Eh
6
FLL Fine CounterRegister
Write only
6Eh
BITLABELDESCRIPTION
0F0LSB of Spindle FLL Fine Counter
1F1Bit 1of Spindle FLL Fine Counter
2F2Bit 2of Spindle FLL Fine Counter
3F3Bit 3of Spindle FLL Fine Counter
4F4Bit 4of Spindle FLL Fine Counter
5F5Bit 5of Spindle FLL Fine Counter
6F6Bit 6of Spindle FLL Fine Counter
7F7Bit 7of Spindle FLL Fine Counter
11/17
L6275
INTERNALREGISTER DEFINITION
Reg:
Name:
Type:
Address:
BITLABELDESCRIPTION
0THERMALThermal Shutdown = 0 indicates that the chip temperature has exceeded 160°C.
1THERM_WARNThermal ShutdownWarning=0 indicates that the chip temperature is
2ROTOR_STUCK0 = A sequential Spindle BEMF has not been detected
3FAULT1 = Rapid deceleration of the Spindle motor or High frequency on FCOM signal.
4MASK_TIMEMask Time toggled to ”0” indicates that the Spindle BEMF is masked.
5ERROR_LOCK0 = Indicates error Spindle speed > 16msec/sample, either electrical or
6ALIGN0 indicate that the Spindle is in the Internal Start-Up Align Phase.
7GO0 indicate that the Spindle is in the Internal Start-Up Go Phase.
Reg:
Name:
Type:
Address:
7
Spindle Status Register
Read only
7Eh
The bit will reset (=1) when the temperature falls below 130°C. When Thermal
Shutdown =0, the spindle logic will tristate both high and low side drivers,
protecting the output circuitry.
approximately 25°C before the device goes in thermal shut down.
mechanical.
8
Spindle FLLRegister
Write only
8Eh
BITLABELDESCRIPTION
0SSLEWSpindle PWM (chopping) Slew Rate. 0 = 10VµS, 1 = 20Vµs
1ICPSpindle FLL Charge pump current. 1= 25µA, 0 = 100µA.
2Unused. Set = 0.
3ISNS1 = Puts outputof the Spindle sense amplifier on FCOM pin and changes limit to
4IL1Adjust maximum voltage on Spindle Rsense
5IL0Adjust maximum voltage on Spindle Rsense
6CPL1 = Spindle FLL Charge pump low
7CPH1 = Spindle FLL Charge pump high
0PKV_1VCM Parking Voltage
1PKV_2VCM Parking Voltage
2VR1 = connects internal VR reference (2V) to level shift Opamp (for
3RT0(*)VCM Retract Time
4DOUBLE1 = Spindle Internal Start-Up Align and Energization time doubled.
5VCM_ENEnableVCM section. 1 = Enable, 0 = Disable.
6RT1(*)VCM Retract Time
7RETRACT1= VCM retract
(*) When program Retract Time (RT0and RT1), Bit 2 REG#8Eh must be always written to0.
9
SystemControl Register
Write only
9Eh
Vcm calibration).
”PKV_1””PKV_2””PARKING VOLTAGE”
000.850V
010.650V
101.600V
111.150V
”RT0””RT1””RETRACT TIME”
00160ms
01320ms
1080ms
11160ms
13/17
L6275
INTERNALREGISTER DEFINITION
Reg:
Name:
Type:
Address:
BITLABELDESCRIPTION
0Unused. Set = 0
1Unused. Set = 0
2Unused. Set = 0
3Unused. Set = 0
4FLL_OUT1 = Spindle Mech/Elec (see bit 5 register 2) output, 0 = Spindle
5REV_BRAKESpindle Reverse Brake command. 1 = Brake. “0” has to be
6Unused. Set = 0
7VB/DIS1 = Disable Vboost
Reg:
Name:
Type:
Address:
10
Test ControlRegister
Write only
AEh
zero crossing output.
reinserted to enable the spindle start up.
11
VCM ControlRegister
Write only
BEh
BITLABELDESCRIPTION
0VCMSVCM PSM (chopping) Slew Rate. 0 = 10V/µs, 1 = 20V/µs
1VCMH1 = Forces VCM outputs to be High in PSM mode.
2SLEEPUnused (for future power saving mode).
3COMSLEWSpindlePWM (phase commutation) Slew Rate. 0 = 30Vµs, 1 =
4Unused. Set = 0
51 = Tristate the VCM outputs for half of the Retract Time during
61 = Brakes the VCM outputs for half of the Retract Time during
7Unused. Set = 0
14/17
2Vµs.
retract.
retract.
INTERNALREGISTER DEFINITION
L6275
Reg:
Name:
Type:
Address:
12
Chip ID Register
Read only
FFh
BITLABELDESCRIPTION
0ID_REV_0Minor Revision Bit 0.
1ID_REV_1Minor Revision Bit 1.
2ID_REV_2Minor Revision Bit 2.
3ID_REV_3Minor Revision Bit 3.
4ID_REV_4Minor Revision Bit 0.
5ID_REV_5Minor Revision Bit 1.
6ID_REV_6Minor Revision Bit 2.
7ID_REV_7Minor Revision Bit 3.
Figure 3. ApplicationCircuit.
5V_VDD
22µF
16V
(1)
1µF
12V_VCC
5V_VDD
STN4NE03
5K(4)
20K
18.2K
100nF
2.2µF
220pF(3)
5K(4)
15K
22µF
16V
(1)
1N4148
51K
10nF(4)
VCC
20µH
1Ω
2N2222
POR_DELAY
100nF
22µF
16V
(1)
CS
CP
SW1
BRK_CAP
PWM/SLEW
DGND
SPN_COMP
AGND
CLK_MON
GND
VDD
TR_5V
Voice Coil Ground
Power Ground
100nF
VCCRSENSE ISENSE2CTAP
24
23
33
36
12
3
14
44
42
40
8
19
35
VCM_CAL22V12/2DAC ERROR_IN ERROR_OUTSENSE_OUT
0.3(1W)
13,436,95
2041393837
10K62K10K
Analog Ground(1) This capacitor must be
Digital Ground
CTAP
OUT_A
OUT_A
1nF
(2) Place these components close to thedevice
(3) Do not mount this component if Spindle Linear mode is used
(4) Do not mount this component if Spindle Pwm mode is used
OUT_B
10
Tantalum
OUT_B
7
OUT_C
OUT_C
4
28
26
27
30
29
21
32
25,31
11
1
34
15
18
17
16
VCM_GND
VCM_A-
SENSE_IN+
VCM_A+
SENSE_INFLL-FILTER
FLL_RES
VCC
INDEX
FCOM
PORB
SYS_CLK
SCLK
SDATA
SDEN
D99IN1052
VCM_A-
0.25(1W)
62K
4.7K
1µF
VCM_A+
620K
100nF
VCC
INDEX
FCOM
5V_VDD
PORB
SYS_CLK
SCLK
SDATA
SDEN
15/17
L6275
DIM.
mminch
MIN.TYP.MAX.MIN.TYP.MAX.
A1.600.063
A10.050.150.002
0.006
A21.351.401.450.0530.055 0.057
B0.300.370.450.012 0.014 0.018
C0.090.200.004
0.008
D12.000.472
D110.000.394
D38.000.315
e0.800.031
E12.000.472
E110.000.394
E38.000.315
L0.450.600.750.018 0.0240.030
L11.000.039
K0°(min.), 3.5°(typ.), 7°(max.)
OUTLINE AND
MECHANICAL DATA
TQFP44 (10 x 10)
D
D1
A1
2333
34
B
44
1
e
11
TQFP4410
22
E
E1
12
L
0.10mm
.004
Seating Plane
B
K
A
A2
C
16/17
L6275
Information furnished is believed to be accurate and reliable. However, STMicroelectronics assumes no responsibility for the consequences
of use of such information nor for any infringement of patents or other rights of third parties which may result from its use. No license is
granted by implication or otherwise under any patent or patent rights of STMicroelectronics. Specification mentioned in this publication are
subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products
are not authorized for use as critical components in life support devices or systems without express written approval ofSTMicroelectronics.
The ST logois a registered trademark of STMicroelectronics
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