MAS5505T

The MAS5505T features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.In particular, the error amplifier output depends on the VFB pin voltage. When the output current increases, the output capacitor is discharged and so the VFB pin decreases. This produces increase of the error amplifier out- put, so allowing a higher value for the peak inductor current. For the same reason, when due to a load transient the output current decreases, the error amplifier output goes low, so reducing the peak inductor current to meet the new load requirements.

This input controls the recovery function of the MAS5505T Receive PLL and can be driven by the carrier detect output of optical modules or from external transition detection circuitry. When this input is HIGH the input data stream (RDIN) is recovered normally by the Receive PLL. When this input is LOW the data on the inputs RDIN will be internally forced to a constant LOW, the data outputs RDOUT will remain LOW, the Link Fault Indicator output LFIN forced LOW and the clock recovery PLL forced to lock onto the clock frequency generated from REFCLK.Stress greater than those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions greater than those indicated in operational sections of this specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect reliability.

To allow for simple in-system reprogrammability, the MAS5505T does not require high input voltages for pro-gramming. The device operates from a single power supp ly , 4. 5V to 5. 5V , for both the program an dread operations. The MAS5505T is enabled through the chip select pin (CS) and accessed via a three-wire interface consisting of the Serial Input (SI), Serial Output (SO), and the Serial Clock (SCK). All programming cycles are self-timed, and no separate erase cycle is required before programming.