Analog Devices Inc./Maxim Integrated MAX6409BS33

Overview

MAX6409BS33 from Maxim Integrated is a precision ultra-low-power voltage detector IC designed for battery and power-supply monitoring in portable systems. It features a factory-trimmed 3.30V reset threshold (±2.5% over -40°C to +85°C), active-low push-pull output, manual reset input (MR), and guaranteed valid output down to VCC = 1.0V. It operates across 1.2V–5.5V supply range and consumes only 500nA typical supply current.

For engineers reviewing the MAX6409BS33 datasheet, MAX6409BS33 pinout, MAX6409BS33 application, or MAX6409BS33 equivalent, key selection criteria include its fixed 3.30V detection threshold, UCSP-4 package footprint, immunity to short VCC transients, and compatibility with low-voltage microcontroller reset circuits requiring guaranteed logic state below 1V.

Technical Context

The MAX6409BS33 uses a precision bandgap reference comparator architecture with internal hysteresis of 9.5mV to prevent chatter during threshold crossing. Its output asserts low when VCC falls below 3.30V and remains asserted until VCC rises above the threshold plus hysteresis - a behavior confirmed for all operating temperatures from -40°C to +85°C.

It integrates an internal 50kΩ pullup on the MR pin, enabling direct connection to a momentary switch to ground without external components. Propagation delay is 20–42µs (VCC falling) and 80–120µs (VCC rising), with startup time of 88µs from VCC = 0 to threshold, ensuring fast, deterministic reset timing in battery-powered applications.

Key Specifications

Pinout & Package

MAX6409BS33 is housed in a 4-bump (2×2 mm) chip-scale package (UCSP-4), offering 70% smaller footprint than SC70. The package has no leads; solder bumps contact PCB pads directly.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX6409BS34, the MAX6409BS33 offers tighter alignment to nominal 3.3V rails; compared with TLV803EB33DBZR, it delivers 3.6× lower supply current and integrated MR-critical for long-life, serviceable portable designs.

Availability

MAX6409BS33 is available at Aetrix Electronics and suitable for portable medical sensors, industrial handheld scanners, smart wearables, and asset tracking tags requiring stable component supply with long-term lifecycle support.

Supply support for MAX6409BS33 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) is a semiconductor company specializing in high-performance analog, mixed-signal, and power management ICs for industrial, automotive, and consumer applications.

The MAX6406–MAX6411 family was designed specifically for ultra-low-power voltage supervision in battery-critical portable equipment, emphasizing minimal footprint, sub-µA operation, and factory-trimmed accuracy without external components.

FAQ

What is the exact reset threshold voltage of the MAX6409BS33?

The MAX6409BS33 has a factory-trimmed nominal reset threshold of 3.30V, with guaranteed accuracy of ±2.5% over the full operating temperature range of -40°C to +85°C. This value is confirmed in Table 1 of the official datasheet and applies specifically to the "33" suffix variant within the MAX6409 series.

Does the MAX6409BS33 require external components to function?

No, the MAX6409BS33 requires no external components. Its precision bandgap reference, comparator, and push-pull output are fully integrated. The MR pin includes an internal 50kΩ pullup resistor, and the 3.30V threshold is factory-trimmed - eliminating the need for external resistors, capacitors, or calibration circuitry.

Can the MAX6409BS33 operate reliably when the supply voltage drops below 2.0V?

Yes, the MAX6409BS33 guarantees correct output logic state down to VCC = 1.0V. Electrical characteristics including propagation delay, output voltage levels, and threshold detection remain valid across the full specified supply range of 1.2V to 5.5V, making it suitable for deep brownout supervision in Li-ion and coin-cell applications.

What is the package type and size of the MAX6409BS33?

The MAX6409BS33 is packaged in a 4-bump ultra-thin chip-scale package (UCSP-4), measuring 2.0mm × 2.0mm with 0.5mm bump pitch. This package is 70% smaller than SC70 and requires no leads - solder bumps attach directly to the PCB, minimizing footprint and height in space-constrained portable designs.

How does the manual reset (MR) pin function on the MAX6409BS33?

The MR pin on the MAX6409BS33 is an active-low input with an internal 50kΩ pullup to VCC. Pulling MR low asserts the OUT pin (drives it low) regardless of VCC level. OUT remains asserted as long as MR is held low. When left unconnected or tied to VCC, MR is inactive and does not affect reset behavior.