Analog Devices Inc./Maxim Integrated MAX1044CSA

Overview

The MAX1044CSA from Maxim Integrated is a monolithic CMOS switched-capacitor voltage converter that inverts +5V to -5V, delivers 10mA output with 0.5V drop, operates from 1.5V to 10V supply, and features a BOOST pin to raise oscillator frequency above audio band-enabling compact capacitor sizing in portable op-amp power supplies.

For engineers reviewing the MAX1044CSA datasheet, MAX1044CSA pinout, MAX1044CSA application, or MAX1044CSA equivalent, this page provides verified pin functions, confirmed efficiency (98% typ), validated BOOST-driven frequency scaling, and real-world load-dependent output resistance behavior for low-power analog rail generation.

Technical Context

The MAX1044CSA implements a four-MOSFET charge-pump topology with on-chip oscillator and internal regulator bypass control via LV pin. Its BOOST pin raises internal oscillator frequency by ~6× when tied to V+, reducing output impedance and ripple while shifting switching noise out of audible range.

Unlike the ICL7660, the MAX1044CSA supports active LV grounding across full 1.5V–10V input range, enabling stable operation down to 1.5V without external diodes-while maintaining 200μA max no-load supply current at 5V and 98% typical power-conversion efficiency at RL = 5kΩ.

Key Specifications

Pinout & Package

MAX1044CSA uses an 8-pin SO (Small Outline) package with 1.27mm pitch, JEDEC MS-012AC compliant footprint, and exposed pad not connected internally.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar voltage inverter applications.

Compared with ICL7660CSA, MAX1044CSA offers superior EMI control and low-voltage flexibility; compared with MAX660ESA, it trades output current for smaller footprint and lower quiescent power-making it optimal for space- and battery-constrained instrumentation.

Availability

MAX1044CSA is available at Aetrix Electronics and suitable for portable telephones, handheld instruments, and panel meters requiring stable component supply with commercial-temperature qualification and SO-package manufacturability.

Supply support for MAX1044CSA includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and power-management ICs for industrial, medical, and communications applications.

The MAX1044CSA belongs to Maxim's switched-capacitor voltage converter product line, engineered for low-noise, inductor-free DC-DC conversion in space-constrained portable and test equipment.

FAQ

What is the function of the BOOST pin on the MAX1044CSA?

The BOOST pin on the MAX1044CSA raises the internal oscillator frequency by approximately six times when connected to V+. This increases switching frequency from ~5kHz to ~30kHz, reducing output impedance, output ripple, and required external capacitor values-critical for minimizing audible noise and PCB area in portable designs. When left open, the MAX1044CSA operates at its nominal frequency; the BOOST pin has no effect when an external clock drives the OSC pin.

Can the MAX1044CSA generate voltages other than inverted outputs?

Yes, the MAX1044CSA supports multiple configurations: inversion (e.g., +5V → –5V), voltage doubling (+5V → +10V), voltage division (e.g., +5V → +2.5V), and multiplication. These modes are implemented using external capacitor and diode arrangements-not internal configuration bits. The MAX1044CSA itself remains a fixed-function charge-pump core; circuit topology determines output polarity and ratio. Datasheet Figures 8–11 detail each configuration.

What is the minimum supply voltage for reliable operation of the MAX1044CSA?

The MAX1044CSA operates reliably down to 1.5V when the LV pin is grounded-a design feature enabling use with single-cell alkaline or Li-ion batteries. At 1.5V, output capability is reduced (e.g., ~2mA into –1.5V), but regulation and startup remain functional across the full 0°C to +70°C commercial temperature range. Leaving LV open restricts minimum V+ to 3.0V per datasheet specifications.

How does the MAX1044CSA compare to the ICL7660 in terms of efficiency and output current?

The MAX1044CSA and ICL7660 share identical baseline efficiency (98% typ) and output current (10mA with 0.5V drop) under matched conditions. However, the MAX1044CSA achieves higher effective efficiency at light loads via BOOST-driven frequency scaling, which lowers output resistance and ripple-reducing losses in downstream filtering. Both parts deliver identical performance when operated identically; the MAX1044CSA adds design flexibility, not raw parameter improvement.

Is the MAX1044CSA pin-compatible with the ICL7660CSA?

Yes, the MAX1044CSA is fully pin-compatible with the ICL7660CSA in the 8-pin SO package: all eight pins match function-for-function, including shared CAP+, GND, CAP-, VOUT, LV, OSC, and V+ assignments. Pin 1 (BOOST on MAX1044CSA, N.C. on ICL7660CSA) is safe to leave unconnected in legacy designs-ensuring seamless drop-in replacement where BOOST functionality is unused.