TLS24320

The TLS24302 and TLS24306 are read/write BiCMOS preamplifiers designed for use with magnetoresistive (MR)/thin- ilm (TF) recording heads. The MR element is used for reading and the inductive thin-film section of the head is used  or writing. The  TLS24302 and TLS24306  preamplifiers implement a current-bias/current-sense architecture. Both  TLS24302 and TLS24306  have a single-ended read  nput with a fully differential read (RDX, RDY) output that operates from a single 5-V supply.

The write-head current I_I(W) and MR-head bias current I_I(BIAS) are programmable using external resistors. Recovery time is reduced by holding BHV/IBON low during the write mode. Multichannel servo write is achieved by taking FLT/SE higher than V_CC by at least 1.2 V. An optional booster circuit can be used to achieve higher operating frequencies.A fault terminal (FLT/SE) goes low when the WDX/WDY input frequency is low, a head is shorted or open, there is no write current (Ix or Iy), or if V_CC is low. Additionally, the preamplifiers provide an optional thermal-asperity detection circuit that can be enabled by using an optional metal mask during the fabrication process. Table 1 lists the functions of  TLS24302 and TLS24306  that can be changed by a custom metal mask during the fabrication process. Contact your local Texas Instruments (TI) sales office or representative for further information.The TSSOP packages optimize the preamplifiers for package-on-arm applications.