LDIC LD3501-6, LD3501-4, LD3501-2, LD3501-16, LD3501-8 Datasheet

LD3501-XX

2, 4, 6, 8, up to 16-Channel

+5V, MR Head Preamplifier

version 1.5

DESCRIPTION

The LD3508 is a 5-Volt only 8-channel MR Pre-Amp,
one of the families of LD35XX MR Pre-Amp
integrated circuit products designed for use with
Magneto-Resistive recording heads. It is based on
external component design to provide maximum
programmability. These devices support 2, 4, 6, 8, 10
up to 16-channel MR Heads. It contains an MR low
noise read amplifier, a thin film head write driver and
mode select to provide the ability to control the
multiple operation modes. External components
provide programmable Read Gain, Programmable
Thermal Asperity Threshold Detection, and Correction,
Write Currents and MR bias current. This product
family requires 5V-supply voltage. These devices are
available in VQFP, or flip chip.

FEATURES

Ø 70 to 120Mhz - 3db Bandwidth
Ø Typical write current rise/fall time = 3.5ns (typical

conditions)

Ø Programmable Read Amplifier Gain through

external voltage.

Ø Programmable Thermal Asperity Threshold

Detection and correction through external resistor.

Ø MR Head: Differential current bias, Voltage sense

MR Head Read Amp.

Ø Programmable MR head bias current range 6-16

mA

Ø MR read input noise = 0.6nv/√Hz
Ø Programmable write current range 15 - 45 mA
Ø Write head unsafe sensing
Ø Head Swing = 8Vp-p differential
Ø Servo write capability
Ø Power on Reset
Ø Power supply fault protection

Write

Interface

Read

Interface

Read

Bias

Source

Write

Data

Control

Block

8 - Channel R/W, MR Bias

Write Driver

Dummy

Head

Interface/Command Control Block

WDY CN GNDR GND

VCC HUS

RDX

RDY

CBX CBY

HR0

HW0X

HW0Y

HR7

HW7X

HW7Y

SWSBY

WRN

CHEN

WI

BLOCK DIAGRAM

WDX TAEN

RG

Head

Select

HS0 HS1 HS2

RI

RDMY

POR

Current

Generator

Head

Unsafe

Prog.

Thermal

Asp. Detc.

Amplifier

Prog. Gain

Post Pre
Amplifier

CZX CZY

LD3501-XX

2, 4, 6, 8, up to 16-Channel

+5V, MR Head Preamplifier

Page 10 version 1.5

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48

47

46

45

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36

35

HS1

HS2

CHEN

RWN

SWSBY

HR7

HW7Y

HW7X

HR6

HW6Y

RDMYRGTAENCNGNDR

HW0X

HW0Y

HR0

HW1X

HW1Y

HW6X

HW5Y

HR5

HW5X
HR4
HW4Y

HR3

HW4X

HW3Y
HW3X
HR2

HW2X

HW2Y

HR1

HS0

WDY

HUS

WDX
WI
RI

GND

VCC

RDY
RDX
CBY

CZY

CBX

CZX

LD3501-XX

8-channel

FLIP CHIP (C4) PAD

FRAME

(C4 BUMPS UP)

Preliminary (Subject to change)