MAXIM MAX8564EUB+

The MAX8563/MAX8564/MAX8564A ultra-low-output dual and triple LDO controllers allow flexible and inexpensive point-of-load voltage conversion in motherboards, desknotes, notebooks, and other applications. These parts feature a 0.5V reference voltage with ± 1 % accuracy providing tight regulation of the output voltage. The MAX8563 has three n-channel MOSFET controller outputs, and the MAX8564/MAX8564A has two controller outputs. Each controller output is adjustable from 0.5V to 3.3V when VDD = 12V and between 0.5V and 1.8V when VDD = 5V. Each output is independently enabled and asserts a POK signal when the output reaches 94% of the set value. Each output is protected against a soft short-circuit condition by an undervoltage comparator that disables the output when it drops to under 80% of the set voltage for more than 50μs. For a catastrophic short condition, the regulators are shut down immediately if the output drops below 60% of the set voltage. The MAX8563 is available in a 16-pin QSOP package, and the MAX8564/MAX8564A are available in a 10-pin package. The MAX8563/MAX8564/MAX8564A triple and dual LDO controllers allow flexible and inexpensive voltage conversion by controlling the gate of an external n-MOSFET in a source-follower configuration. The MAX8563/MAX8564/MAX8564A consist of multiple identical LDO controllers. Each LDO controller features an enable input (EN_) and a power-OK output (POK_). The MAX8563/MAX8564/MAX8564A also include a 0.5V reference, an internal regulator, and an undervoltage lockout (UVLO). The transconductance amplifier measures the feedback voltage on FB_ and compares it to an internal 0.5V reference connected to the positive input.

• ±1% Feedback Regulation
• Adjustable Output Voltage Down to 0.5V
• Can Use Ceramic Output Capacitors
• Wide Supply Voltage Range Permits Operation from 5V or 12V Rails
• Individual Enable Control and POK Signal Allows Sequencing
• Overload Protection Against Soft Short-Circuit Condition
• Undervoltage Short-Circuit Protection
• Drive n-Channel MOSFETs

• Motherboards
• Ultra-Low-Dropout Dual/Triple Power Supplies
• Voltage Regulators
• Desknotes and Notebooks
• Low-Voltage DSP, µP, and Graphic Cards
• Microcontroller Power Supplies