General Description

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 µMAX® package.

Features

♦ MAX8563: 3 Outputs

♦ MAX8564/MAX8564A: 2 Outputs

♦ ±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

Applications

   Motherboards

   Dual/Triple Power Supplies

   Desknotes and Notebooks

   Graphic Cards

   Ultra-Low-Dropout

   Voltage Regulators

   Low-Voltage DSP, µP, and Microcontroller Power Supplies