HELICAL DRUM

MicroPhysics

MicroPhysics Helical Tape Head Tester (HHT)

Electrical Test and Flying Height in a Single Unit

MicroPhysics Helical Tape Head Tester (HT²) has been designed to be the ultimate tool for R&D and failure analysis of helical tape heads. Electrical test, including embedded servo and active track following, is leveraged from MicroPhysics Disk Head Tester Technology. Flying height measurement is accomplished using systems from MicroPhysics Tape Spacing Analyzer. Together, these technologies allow you to electrically test heads with track widths well below a micron, while simultaneously measuring and verifying head/tape contact optically.

Product Features:

Novel Drum Design: The drum allows you to load up to four different segments of tape, one per quadrant. This capability allows you to test with clear tape (for flying height) at the same time as magnetic tape (for electrical test).

Full Quad Servo: The HT² utilizes a true quadrature closed-loop servo for track position during write/read and offtrack measurements.

Mechanical Features:

Adjust Head Penetration, Track Position, Pitch, and Roll under computer control

Tooling designed to be extremely light and stiff to allow fast servo actuation.

Integrated with electronics to provide very sophisticated track following servo motion.

Flyheight measured with sub-nanometer resolution.

System specifications are subject to change.

Tests:

Amplitude (TAA)	Resolution	Overwrite	SNR	Track Profile
Amplitude Assy	Pulse Width (PW50)	Timing Assy	Stability	Popcorn Noise
D50	Saturation Curves	Modulation	Bit Shift

HT² Tooling and Drum

Great Tracking and Fly Height Verification:

As track widths get smaller and head/tape speeds increase, it can become difficult to determine what is going on with prototype heads and failures. MicroPhysics system allows you the ultimate capabilities for head positioning, track following, and optical verification of contact, together with an integrated electrical test system.

Specifications:

Bandwidth: 100 KHz to 100 MHz (-3 dB)

Head/Tape Speed: 1 to 25 m/s

Preamp: MR or Inductive available

Precomp/Equalization: Personalized card to meet customer requirements

Digitizer: Up to 500 Msamples/sec

Data:

Electrical Data is shown from MicroPhysics DHT hard disk head tester for illustrative purpose. Helical Tape Head Tester uses same tooling and servo tracking techniques. Spacing data from MicroPhysics TSA.

0.17 micron (6.7 u”) reader – Repeated amplitude track profiles
(data from hard disk tester for illustrative purposes)