UC3910D

ADCs/DACs - Special Purpose Overview

The UC3910D is a 4-bit DAC and voltage monitor circuit designed for Intel Pentium Pro and high-end microprocessor power supplies. It integrates a precision 5V reference capable of sourcing 10mA, a 4-bit digital-to-analog converter with 100mV resolution, and programmable window comparators. The device operates within a supply voltage range of 7V to 12V, drawing 2mA to 12mA depending on VCC. It features undervoltage lockout, overvoltage protection with SCR driver capability, and open-collector outputs. The UC3910D is housed in a 16-pin SOIC package and supports commercial temperature operation from 0°C to 70°C.

ADCs/DACs - Special Purpose Feature Summary

• Integrated 4-bit DAC with 100mV step resolution (2.0V to 3.5V output) and 0.5% combined accuracy
• Precision 5V voltage reference with 10mA sourcing capability
• Programmable undervoltage and overvoltage fault windows via external resistor divider
• Overvoltage comparator drives external SCR with up to 65mA sink current

ADCs/DACs - Special Purpose Applications

• Intel Pentium Pro processor power supplies
• Adjustable DC/DC converters ranging from 2.0VDC to 3.5VDC
• High-end microprocessor power management circuits

ADCs/DACs - Special Purpose Procurement Notes

Verify the specific ordering suffix 'D' corresponds to the 16-pin SOIC package variant. Confirm the device status as Not Recommended for New Designs (NRND) if new production is planned, or check for the lead-free alternative UC3910DG4 which shares identical electrical specifications and packaging.

ADCs/DACs - Special Purpose Selection Notes

Select this component when designing power supplies for legacy Intel Pentium Pro architectures requiring precise voltage monitoring. Ensure the external resistor divider network sets the OV/UV thresholds within the 5% to 15% range relative to the DAC output. Verify that the load on the VREF pin does not exceed the 10mA sourcing limit to maintain specified accuracy.

ADCs/DACs - Special Purpose Part Context

The UC3910D belongs to the UC1910/UC2910/UC3910 family, differentiated primarily by operating temperature ranges. While the UC1910 covers -55°C to 125°C and the UC2910 covers -25°C to 80°C, the UC3910 is rated for commercial temperatures (0°C to 70°C). All variants share the same block diagram and pin configuration.

ADCs/DACs - Special Purpose Replacement Considerations

The UC3910DG4 is the lead-free version of the UC3910D with identical functionality and packaging. No other direct functional substitutes are documented in the provided datasheet.