3A BUS TERMINATION REGULATOR
DESCRIPTION
The UTC UR5516A is designed to provide a regulated voltage
with bi-directional output current for DDR-SDRAM termination.
Current-limit work to limit the short-circuit current, on-chip thermal
shutdown provides protection against any combination of overload
that would create excessive junction temperature. The output voltage
tracks the voltage at VREF pin. A resistor divider connected to VIN,
GND and VREF pins is used to provide a half voltage of VIN to VREF
pin. In addition, an external ceramic capacitor and an open-drain
transistor connected to VREF pin provides soft-start and shutdown
control respectively. Pulling and holding the VREF to GND shuts off
the output. The output of UTC UR5516A will be high impedance
after being shut down by VREF or thermal shutdown function.
FEATURES
* Provide bi-direction current
- Sourcing or sinking current up to 3A
* 1.25V/0.9V output for DDR I/II applications
* Fast transient response
* High output accuracy
- ±20mv over load, VOUT offset and temperature
* Adjustable output voltage by external resistors
* Current-limit protection
* On-chip thermal shutdown
* Shutdown for standby or suspend mode |
