حفاظت مدار محدودکننده‌های ولتاژ گذرا (تی وی اس) تجهیزات حفاظت در برابر اضافه‌ولتاژ گذرا (اس پی دی)

Product Attributes

Introduction

Critical loads often employ parallel-connected power supplies with redundancy in order to enhance system reliability. The MAX8535/MAX8536/MAX8585 are highly integrated but inexpensive MOSFET controllers that provide isolation and redundant power capability in high-reliability systems. The MAX8535/MAX8585 are used in 12V systems, and have an internal charge pump to drive the gates of the n-channel pass elements to V_CC + 10V. The MAX8536 is used in 3.3V and 5V systems, with a chargepump output of V_CC + 5V. During startup, the MAX8535/MAX8536/MAX8585 monitor the voltage drop across external MOSFETs. Once VCC approaches or exceeds the bus voltage, the MOSFETs are turned on. The MAX8535/MAX8536/ MAX8585 feature a dual-purpose TIMER input. A single external resistor from TIMER to ground sets the turn-on speed of the external MOSFETs. Optionally, the TIMER input can be used as a logic-enable pin. Once the device is turned on, the MAX8535/MAX8536/MAX8585 monitor the load, protecting against overvoltage, undervoltage, and reverse-current conditions. Overvoltage and undervoltage fault thresholds are adjustable and can be disabled. The current-limit trip points are set by the external MOSFETs’ RDS(ON), reducing component count. An open-drain logic-low fault output indicates if an overvoltage, undervoltage, or reverse-current fault occurs. All devices come in a space-saving 8-pin μMAX package and are specified over the extended -40℃ to +85℃ temperature range.

Features

• Simple, Integrated, and Inexpensive ORing MOSFET Controller
• ORing MOSFET Drive for 12V (MAX8535/MAX8585) and 3.3V or 5V (MAX8536) Bus
• Eliminates ORing Diode Power Dissipation and Reverse Leakage Current
• Provides aleph + 1 Redundant Supply Capability for Highly Reliable Systems
• Isolates Failed Supply from Output Bus in <1µs
• Reverse-Current Flow Detection
• Programmable Soft-Start
• Logic-Enable Input
• Adjustable Overvoltage and Undervoltage Trip Points
• Fault-Indicator Output
• Space-Saving 8-Pin #MAX Package

Applications

• Silver Box Supplies for Servers
• On-Board Redundant Power Supplies in Blade Servers
• Network/Telecom Power Supplies
• Rectifiers
• Redundant Power Supplies in High-Availability Systems