MAX840ISA+T

Overview

The MAX840ISA+T is a charge pump integrated circuit designed for cellular telephone transmitter applications. It generates regulated negative output voltages, specifically -2V and adjustable ranges from -0.5V to -9.4V, from a single 2.5V to 10V supply input. The device operates in the industrial temperature range of -40°C to +85°C and is housed in an 8-pin SOIC package.

Feature Summary

• Generates regulated negative bias voltages for GaAsFET or similar components
• Operates from a single positive supply voltage ranging from 2.5V to 10V
• Provides specific -2V output option alongside programmable negative voltage generation

Applications

• Cellular telephone transmitter biasing
• GaAsFET gate bias regulation
• Negative voltage generation for RF front-end modules

Procurement Notes

Verify the exact suffix against the manufacturer's current datasheet to confirm pinout and electrical specifications. Ensure the component meets the required operating temperature range for the intended environment. Cross-reference the ordering information with official Analog Devices documentation to avoid counterfeit parts.

Selection Notes

Select this component when a compact solution is needed to generate stable negative bias voltages from a single positive rail. It is suitable for space-constrained mobile designs requiring efficient charge pump topology without external inductors. Consider the output current requirements and input voltage range compatibility with the system power supply.

Part Context

This part belongs to the Maxim Integrated family of charge pump regulators, specialized for portable wireless communication devices. It addresses the need for negative bias supplies in RF circuits where multiple voltage rails are typically unavailable or inefficient to generate using linear regulators.

Replacement Considerations

Check for direct pin-to-pin replacements within the MAX840 series or newer generations from Analog Devices. Verify that any substitute maintains the same output voltage characteristics and package dimensions.