PIN DESCRIPTIONS

20-CHANNEL, HIGH-PERFORMANCE, THIN-FILM HEAD, REAOIWRITE

NAME VO DESCRIPTION

Head Select: selects one of up to 19 heads. HSO and HS 1 also select which bank of heads is written to during servo write when

OBANK

is pulled low (heads 0 - 4 for HSO and HS1

=

low, heads 5 - 9 for HSO

=

HSO- HS4 I" high and HS1

=

low, heads 10 -14 for HSO

=

low and HS1 = high, and heads 15 - 19 for HSO and HS1

=

high). HSO also selects which bank of heads is written to during servo write when

QBANR

is pulled high (heads 0 - 9 for HSO

=

low and heads 10 - 19 for HSO

=

high)

HOX- H19X

I/O X,Y Head Terminals HOY - H19Y

Write Data Input: Differential PECl WDI,

W!5T

I" input signal, negative transition

toggles direction of head current Chip Select: high level signal puts

cs

^I chip in sleep mode, low level wakes chip up

ReadlWrite Select: high level

RiW

I" selects read mode, low level selects write mode

Write Unsafe: open collector output:

WUS 0" high level indicates writes unsafe condition

WC Write Current Adjust: a resistor adjusts level of write current RDX- ROY 0" Read Data Output: differential

output data

VCC +5VSupply

GND Ground

Quad Bank Select: low level selects four banks of heads for servo write

<:iI3ANK

(0 - 4,5 - 9,10 -1 4and 15 -19); high level selects two banks of heads for servo write (0 - 9 and 10 - 19) Servo Write: when pulled low, servo WSER write feature is enabled on selected

heads

" May be wire-ORed for multi-chip usage.

2-82 VTC Inc., 2800 East Old Shakopee Road, Bloomington, MN 55425, 612-853·5100

DC CHARACTERISTICS Unless otherwise specified, recommended operating conditions apply.

PARAMETER SYM CONDITIONS MIN TYP MAX UNITS

Read Mode TBD TBD

VCC Supply Current Icc Write Mode TBD TBD mA

Idle Mode TBD TBD

Read Mode TBD TBD

VDD Supply Current IDD Write Mode TBD TBD mA

Idle Mode TBD TBD

Read Mode 250 TBD

Power Dissipation (T J = 125°C) PD Write Mode: Iw=20mA 650 TBD mW

Idle Mode 25 TBD

Input Low Voltage VIL TTL -0.3 O.B V

Input High Voltage VIH TTL 2.0 Vee +0.3 V

Input Low Current IlL VIL = O.BV, TTL -200 JlA

Input High Current IIH VIH = 2.0V, TTL 100 JlA

WDI, WDI Input High Voltage VIH Pseudo ECL Vee -1.0 Vee - 0.7 V

WDI, WDI Input Low Voltage VIL Pseudo ECL Vee -1.9 Vee -1.6 V

WDI, WDI Input High Current IIH VIH = Vee - 0.7V 100 JlA

WDI, WDllnput Low Current IlL VIL = Vee - 1.6V BO JlA

WUS Output Low Voltage VOL IOL=4mA 0.35 0.5 V

VDD Fault Voltage VDDF 9.5 10 10.5 V

VDD Servo Mode Fault VDDFS 5.5 5.B 6.1 V

VCC Fault Voltage VeeF 3.B 4 4.3 V

Write Mode, 0 < Vee 3.BV,

-200 +200

0< VDD < 9V

Head Current (HnX, HnY) IH JlA

Write Mode, 0 < Vee 5.5V,

-200 +200

0< VDD < 13.2V

VTe Inc., 2800 East Old Shakopee Road, Bloomington, MN 55425, 612-853·5100 2-B3

WRITE SERVO CHARACTERISTICS

PARAMETER SYM CONDmONS MIN TYP MAX UNITS

VCC Supply Current lee Servo Mode TBD mA

VDD Supply Current 100 Servo Mode, Voo = 7V ±10% TBD rnA

Power Dissipation Po Servo Mode @ Iw = 15mA TBD W

Servo Write Current Tolerance -10 +10 %

Servo Write Current Range 5 15 mA

Rise/Fall Time LH = 0.51lH, Iw = 15mA, 7 ns

@ Voo=7V

Asymmetry LH =0, RH =0 0.5 ns

WDllnput 1 15 MHz

READ CHARACTERISTICS Unless otherwise specilied, recommended operating conditions apply, CL (RDX, RDY) < 20pF and RL (RDX, RDY) = 1 kll.

PARAMETER SYM CONDmONS MIN TYP MAX UNITS

Differential Voltage Gain Av VIN = 1 mVp-p@300kHz 120 150· 180 VN

-1 dB, Ilsi < 5Q, VIN = 1 mVp·p 50

@300kHz

Bandwidth BW MHz

-3dB, IZsl < 5Q, VIN = 1 mVp·p @300kHz 75

Input Noise Voltage ein BW = 15M Hz, LH = 0, RH = 0 0.60 0.75 nVlVHz

Differential Input Capacitance CIN VIN = 1 mVp-p,

I

= 5MHz 9 14 pF

Differential Input Resistance RIN VIN = 1 mVp-p,

I

= 5MHz, 380 750 Q

(25°C < T A < 125°C)

AC input voltage where the gain

Dynamic Range DR lalls to 90% 01 the gain @ 2 5 mVrms

0.2mVrms input,

I

= 5MHz

Common Mode Rejection Ratio CMRR VCM = 100mVp'p @5MHz 50 60 dB

Power Supply Rejection Ratio PSRR 100mVp-p @5MHzonVoo orVcc 45 50 dB

Unselected channels driven with

Channel Separation CS 100mVp-p @5MHz, Selected 45 50 dB

Channels VIN = OmVp-p Output Offset Voltage IVosl VIN = 0 on selected head,

150 mV

Av= 150

RDX, RDY Common Mode Output Read Mode Vee - 3.0 Vee - 2.8 Vcc - 2.2

Voltage VOCM V

Write Mode Vee- 3.O Vee - 2.8 Vee - 2.2

Single-Ended Output Resistance RSEO f=5MHz 35 Q

Output Current 10 AC coupled load, RDX to RDY 1.5 rnA

.

Nominal gain - other options available

2-84 VTC Inc., 2800 East Old Shakopee Road, Bloominglon, MN 55425, 612-853-5100

VM5252015FC

^~~~_~~I

WRITE CHARACTERISTICS Unless otherwise specified, recommended operating conditions apply, Iw = 20mA, LH = 0.51!H, RH = 30n and fOATA = 5MHz.

PARAMETER SYM CONDITIONS MIN TYP MAX UNITS

WC Pin Voltage Vwc 2.5 V

Write Current Voltage VOH Iwc=35mA 10 11 12 Vp-p

Unselected Head Current IUH 1.0 rnA (pk)

Differential Output Capacitance COUT 18 22

Without damping resistor 3.2 Differential Output Resistance ROUT

With damping resistor 300

WDI Transition Frequency fOATA WUS = low 1.0

Write Current Range Iw 1430n, < Rwc < 5kn 5 35

Write Current Tolerance Lllw Iw range 5mA to 35mA -8 +8

SWITCHING CHARACTERISTICS (see Figure 1) Unless otherwise specified, recommended operating conditions apply, Iw = 20mA, LH = 0.51!H, RH = 30n and fOATA = 5MHz.

PARAMETER SYM CONDITIONS MIN TYP MAX

RJW to Write Mode tRw Delay to 90% of write current 0.2

Delay to 90% of 100mV, 10MHz

R/W

to Read Mode tWR read signal envelope or to 90% 0.5

decay of write current Delay to 90% of write current or

CSto Select tlR to 90% of 100mV, 10MHz read 0.6

signal envelope

CS

to Unselect tlW Delay to 10% of write current 0.6

HSO - HS3 to Any Head tHS Delay to 90% of 100mV, 10MHz read signal envelope 0.4

Safe to Unsafe t01 50% WDI to 50% WUS 0.6 3.6

Unsafe to Safe t02 50% WDI to 50% WUS 1

Propagation Delay t03 From 50% points, LH = 0, RH = 0 30

Asymmetry ASYM WDI has 50% duty cycle and 1 ns

0.2 0.5

rise/fall time, LH = 0, RH = 0

Rise/Fall Time-

t,lt,

LH = 0.51!H, Iw = 20mA 4

Rise/Fall Time

t,lt,

(LH = OI!H) TBD

pF kn n MHz

rnA

UNITS

I!S I!s

I!S I!s I!S I!S I!S ns ns ns

.

Rise/Fail time might vary according to customer nse fall/settle time trade off. Rise/Fail time and settle time Will be selected for max-

^.

ns imum bit cell.

VTC Inc., 2800 East Old SNakopee Road. Bloomington, MN 55425. 612·853-5100 2-85

- -.. _ -.... _ - _ ..

_

-~~. ~ .. ^f~~ VM5252015FC

WUS

HEAD

CURRENT (Iw)

Figure 1: Write Mode Timing Diagram

2-86 VTC Inc.: 2800 East Old Shakopee Road, Bloomington, MN 55425, 612-853-5100

Two-Terminal High-Performance +5V Preamplifiers

VM3200

2 or 4-Channel, 3 to 5-Volt, TIL WDI, Thin-Film or MIG Heads ... 2-89 VM71 00

2, 4, 6 or 8-Channel, TIL WDI, WC Gain = 20, Thin-Film or MIG Heads ... 2-97 VM71110

2,4,6,8 or 10-Channel, TIL WDI, low Noise, low CIN, Thin-Film or MIG Heads ... 2-105 VM7150

2,4 or 8-Channel, PECl WDI, WC Gain = 20, SelVo Write, low CIN, Thin-Film or MIG Heads ... 2-113 VM7160

2,4 or 8-Channel, TIL WDI, WC Gain = 20, SelVo Write, Thin-Film or MIG Heads ... 2-121 VM7164S

4-Channel, TIL WDI, WC Gain = 20, SelVo Write, low CIN, Thin-Film or MIG Heads ... 2-129 VM7170

2 or 4-Channel, TIL WDI, WC Gain = 20, SelVo Write, low CIN, Thin-Film or MIG Heads ... 2-137 VM7200

2,4,6 or 8-Channel, TIL WDI, AV = 200, WC Gain = 20, Thin-Film or MIG Heads ... 2-143 VM723430

2 or4-Channel, TIL WDI, AV= 300, WC Gain = 1, Thin-Film or MIG Heads ... 2-151 VM7646

6-Channel, PECl WDI, low Noise, low CIN, Thin-Film Head Programmable ... 2-157 VM7750F

4 or 6-Channel, PECl WDI, low Noise, low CIN, Thin-Film Head, SelVo Write ... 2-165 VM7800

10-Channel, PECl WDI, low Noise, low CIN, Thin-Film Head, SelVo Write ... 2-173 VM782020

20-Channel, PECl WDI, low Noise, low CIN, Thin-Film Head, SelVo Write ... 2-181

VTC Inc., 2800 East Old Shakopee Road, Bloomington. MN 55425. 612-853·5100 2-87

2-88 VTC Inc., 2800 East Old Shakopee Road, Bloomington, MN 55425, 612-853-5100

~.~:.~ ~~. _,::~# ^{VTC Inc.}

Value the CustomerTM

FEATURES

• High Performance

- Read Gain

=

300,200 or 150 VN

• Power Up/Down Data Protect Circuitry

• Single Power Supply

=

3.3V to 5V ±1 0%

• Fault Detect Capability

• Designed for Two-Terminal, Thin-Film or MIG Heads

• Standard Schottky - Isolated 400 W Damping Resistor (patent pending)

• Available in 2 or 4 Channels DESCRIPTION

The VM3200 is a high-performance, very low-power readlwrite preamplifier designed for use with two-terminal, thin-film or MIG recording heads. This device will operate on a single power sup-ply from 3-volts to 5-volts. This makes the VM3200 ideally suited for both battery-powered and 5-volt disk drive applications.

The VM3200 provides write current switching in the write mode and a low noise data path in the read mode for up to four read/write heads. When deactivated, the device enters a sleep mode that reduces power dissipation to 0.7 mW. Data protec-tion circuitry is provided to ensure that the write current source is totally disabled during power up/down conditions. Write-to-read recovery time ·is minimized by eliminating common mode output voltage swings when switching between modes. Write mode performance is improved by providing 5-volt with 3.3-volt supply differential peak-to-peak head voltage allowing the write current to swing faster.

The VM3200 is available in a variety of package options.

Please consult VTC for package availability.

VTC Inc., 2800 East Old Shakopee Road, Bloomington, MN 55425, 612-853-5100

VM3200

2 OR 4-CHANNEL, 3.3 TO 5-VOL T, TWO-TERMINAL, THIN-FILMIMIG HEAD, READIWRITE PREAMPLIFIER

CONNECTION DIAGRAMS

2Q-lead SOIC, SSOP

August,1994

~.~

_~'f.~

.. !'4 VM3200

ABSOLUTE MAXIMUM RATINGS Power Supply: Junction Temperature ... 150°C Storage Temperature Tstg ... -65° to 150°C Thermal Characteristics, 0JA:

20-lead SOIC ... 90°C/W 20-lead SSOP ... 110°C/W

RECOMMENDED OPERATING CONDITIONS Power Supply Voltage:

Vee ... +3.3V to +5V

±

^10%

The VM3200 part type is available with a wide variety of pos-sible options that allow the device to closely fit different applications. In order to simplify the task of defining the various possible options, ordering information is included here. Please note, not all possible combinations of options may actually have been built. Please consult the factory with any questions.

Man~facturer's~.D.gwVWJ.

320 N 2 XX C

Family

-Part Number Damping Resistor Channel Count (2 or 4) Optional Voltage Gain Capacitance Option

L

Package Code _ _ _ _ _ _ _ _ _ _ _ _ ---l

Revision Designator - - - ' DAMPING RESISTOR

Blank

=

Schottky Diode Connected Damping Resistor N

=

No Internal Damping Resistor

C = Low Capacitance Blank

=

^{Low Noise}

PACKAGE CODES

=

Small Outline Integrated Circuit (SOIC) SS

=

Shrink Small Outline Package (SSOP)

CIRCUIT OPERATION

The VM3200 addresses up to four 2-terminal, thin-film or MIG recording heads, providing switched write current in the write mode, or data amplification in the read mode. Head selection and mode control are determined by the head select lines, HS 1, HS2 and mode control lines, CS,

RIW as

shown in Tables 1 and 2. Internal resistor pullups, provided on the

CS

and

RIW

lines, will force the device into a non-write condition if either control line opens up. The part's operation over a wide range of induc-tive loads makes it suitable for two-terminal MIG heads also.

Write Mode

In write mode, the VM3200 acts as a write current switch with the write unsafe (WUS) detection circuitry activated. When switching from read-to-write mode, write current flows into the

"X" head port. Write current is toggled between the X and Y sides of the selected head in each high to low transition on the write data flip-flop (WDFF).

VTe Inc., 2800 East Old Shakopee Road, Bloomington, MN 55425,612·853·5100

Dans le document Gain of ~ (Page 147-155)

PIN DESCRIPTIONS

20-CHANNEL, HIGH-PERFORMANCE, THIN-FILM HEAD, REAOIWRITE