The MAX662A from Maxim Integrated (now part of Analog Devices) solves a specific board-level problem: a 5 V digital system that must also produce the +12 V a flash memory needs for programming and erase. Rather than add an inductor-based boost regulator, the MAX662A uses a charge pump - a switched-capacitor converter that needs no inductor, only four capacitors - so it generates the +12 V quietly and in minimal space. It is an upgrade of the original MAX662, and MAX662ACSA+T is the RoHS ("+"), tape-and-reel ("T") 8-pin SO option.

The output is regulated, not just multiplied: +12 V ±5% is held while the converter sources a guaranteed 30 mA - enough to program the flash device. The input is a standard logic rail, 4.5 V to 5.5 V, and the quiescent current is a low 185 µA. When the +12 V is not needed, a logic-controlled shutdown (SHDN̅) drops the supply current to 0.5 µA and the output is disconnected - important in a battery or standby system where the programming voltage is only needed occasionally.

The switched-capacitor topology is built around two flying capacitors on the C1+/C1- and C2+/C2- pins, plus input and output reservoir capacitors - the "four capacitors, no inductor" that keep the solution small (about 0.1 in²) and free of the EMI an inductor can radiate. The MAX662A handles the regulation internally, so the designer only sizes the capacitors per the datasheet. It operates over the commercial 0 °C to +70 °C range (C grade) in the 8-pin SO.

Note: Values are taken from the Maxim MAX662A datasheet. Confirm every parameter and the recommended capacitor values against the latest official documentation before committing a design.

MAX662ACSA+T ships in the 8-pin SO (0.150-inch narrow SOIC, package outline 21-0041) - the small body that, with only four external capacitors, lets the whole +12 V generator fit about 0.1 in². Place the flying capacitors (C1, C2) close to the C1+/C1-/C2+/C2- pins, keep the reservoir caps at IN and OUT, and route the switched nodes short to contain the pulsed currents. The dimensional drawing below gives the full mechanical detail.

The 8-pin SO carries the two flying-capacitor pairs, supply, output and shutdown (per the MAX662A datasheet):

• Pin 1 - C1-: Flying capacitor 1, negative terminal.
• Pin 2 - C1+: Flying capacitor 1, positive terminal.
• Pin 3 - C2-: Flying capacitor 2, negative terminal.
• Pin 4 - C2+: Flying capacitor 2, positive terminal.
• Pin 5 - V_CC: Supply input, 4.5 V to 5.5 V; bypass to GND.
• Pin 6 - V_OUT: Regulated +12 V output; reservoir capacitor to GND.
• Pin 7 - GND: Ground.
• Pin 8 - SHDN̅: Logic shutdown input (active-low); 0.5 µA standby, output disconnected.

The MAX662A is a dedicated +12 V flash-V_PP charge pump. The related parts below are other power-management and supervisory devices that share a system with it.

Selection Tips: Choose the MAX662A when a 5 V system needs a small, inductorless, regulated +12 V at up to 30 mA - typically a flash-memory V_PP rail. Pair it with an LDO (MAX604) for the logic rail and a supervisor/watchdog (MAX6368/MAX6369) for the processor housekeeping around the flash device.

Maxim Integrated, now part of Analog Devices, Inc. (ADI), built the MAX662A to give a 5 V board a small, quiet +12 V supply for flash programming - a regulated charge pump that needs no inductor and only four capacitors, with a logic shutdown for intermittent use.

ADI maintains the datasheet, the capacitor-selection guidance and the load/regulation specifications for the part - the basis for a dependable +12 V V_PP rail in minimal board area.