The DS2129 is a triple-output voltage regulator for 27-line, low-voltage-differential (LVD) SCSI termination for SPI-2 and SPI-3 applications using LVD termination networks. The device provides reference voltages and bias currents for LVD-termination resistor pi (π) networks. With a pi network (475Ω, 121Ω, 475Ω), the DS2129 meets the common-mode bias, differential bias, and termination-impedance requirements of SPI-2 (Ultra2) and SPI-3 (Ultra3). The device also provides a 1.3V output for DIFFSENSE signaling, and includes pro- tection features such as thermal shutdown and active current limiting.
The DS2129 is a triple-output voltage regulator designed for 27-line, low-voltage-differential (LVD) SCSI termination in SPI-2 and SPI-3 applications. It provides reference voltages and bias currents for LVD-termination resistor pi networks, meeting common-mode bias, differential bias, and termination-impedance requirements. The device also provides a 1.3V output for DIFFSENSE signaling and includes protection features such as thermal shutdown and active current limiting.
| Operating Temperature Range | 0°C to +70°C |
|---|---|
| TERMPWR Supply Voltage | 2.7V to 5.25V |
| REG1 Output Voltage | 1.75V |
| REG2 Output Voltage | 0.75V |
| DIFFSENSE Output Voltage | 1.3V |
| REG1/REG2 Continuous Output Current | ±200mA |
| Thermal-Shutdown Threshold | +150°C |
| Thermal Resistance (junction-to-ambient) | +77°C/W |
The device meets the requirements of SPI-2 (Ultra2) and SPI-3 (Ultra3) standards.
The TERMPWR supply operates between 2.7V and 5.25V.
The device includes thermal shutdown and active current limiting.