MIC9131BQS

Overview

The MIC9131BQS is a current-mode PWM controller designed for high-voltage telecom DC-DC conversion. It supports input voltages up to 180V, protecting against line transients. The device features an internal oscillator capable of over 2.5MHz operation and synchronization capability up to 6MHz. Key electrical parameters include a 75% maximum duty cycle, 34ns current sense delay, and minimum pulse width under 25ns. Quiescent current is 1.3mA, with shutdown current at 1µA. It offers 90% efficiency and includes soft-start functionality.

Feature Summary

• High voltage start-up circuit allows connection to input voltages as high as 180V
• Internal oscillator supports operation frequencies exceeding 2.5MHz
• Synchronization capability extends operating frequency up to 6MHz
• Integrated soft-start with selectable retry functionality

Applications

• Telecom power supplies
• ISDN network terminators
• Micro- and pico-cell base stations
• Low power dc-dc converters

Procurement Notes

Verify the package type matches the QSOP designation in the specific datasheet revision. Confirm the manufacturer origin, as Micrel Semiconductor was acquired by Microchip Technology. Ensure the component meets required environmental specifications for the intended deployment environment.

Selection Notes

Select this controller for applications requiring robust transient protection in telecom environments. The high input voltage rating simplifies design by integrating components typically needed for surge protection. Consider the synchronization feature if multiple converters must operate in parallel without interference.

Part Context

This component belongs to the MIC9131 series of high-speed telecom controllers. Variants such as MIC9131YM and MIC9131BM share similar functional characteristics but differ in packaging or temperature ratings. The series is engineered for efficient conversion of -48V telecom voltages to logic levels.

Replacement Considerations

Direct substitutes within the same family include MIC9131YM and MIC9131BM. Verify pin compatibility and thermal performance before substitution. Cross-reference datasheets to ensure identical control features and voltage ratings.