Analog Devices Inc./Maxim Integrated MAX6378UR46+T

Overview

MAX6378UR46+T from Maxim Integrated is an ultra-low-power, active-low push-pull voltage detector optimized for 4.63V supply monitoring in battery-powered systems. It features ±2.5% threshold accuracy over temperature, 500nA supply current, and guaranteed operation down to 1V VCC. Its primary circuit role is system reset assertion during brownout conditions in portable medical devices and low-power microcontroller power rails.

For engineers reviewing the MAX6378UR46+T datasheet, MAX6378UR46+T pinout, MAX6378UR46+T application, or MAX6378UR46+T equivalent, key selection criteria include factory-trimmed 4.63V threshold, SOT23-3 package compatibility, push-pull active-low output drive capability, and transient immunity up to 140µs at 30mV overdrive.

Technical Context

The MAX6378UR46+T implements a precision bandgap reference and comparator with internally trimmed resistors to set its 4.63V trip point. It asserts OUT low when VCC falls below VTH and maintains valid logic state down to 1V supply - critical for deep-brownout detection in Li-ion systems.

Its push-pull output drives high-impedance loads without external pull-up, while built-in transient immunity rejects negative-going VCC glitches ≤140µs (at 30mV overdrive). Propagation delay is 9.5µs (typ) with 20µs max across -40°C to +85°C.

Key Specifications

Pinout & Package

MAX6378UR46+T is housed in a 3-pin SOT23-3 package (JEDEC MO-178AA), footprint-compatible with SC70-3 but with higher power dissipation rating (320mW at +70°C).

Key Features

Applications

Equivalent & Alternatives

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

Compared with TLV803EB33DBZR and TPS3808G33DBVR, the MAX6378UR46+T uniquely delivers 4.63V precision detection in a 3-pin push-pull configuration with sub-µA supply current - making it optimal for 5V-system brownout protection where board space and battery life are constrained.

Availability

MAX6378UR46+T is available at Aetrix Electronics and suitable for portable medical sensors, industrial PLC I/O modules, and smart meter battery backup systems requiring stable component supply and long-term manufacturability.

Supply support for MAX6378UR46+T 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 and mixed-signal ICs for power, sensing, and interface applications, with emphasis on reliability and integration.

The MAX6375–MAX6380 family was developed specifically for ultra-low-power voltage monitoring in space- and energy-constrained systems, targeting battery longevity and minimal external component count.

FAQ

What is the exact factory-trimmed threshold voltage of MAX6378UR46+T?

The MAX6378UR46+T has a nominal threshold voltage of 4.63V, with ±2.5% tolerance over the full -40°C to +85°C operating temperature range. This value is laser-trimmed at wafer test and verified per Table 1 in the datasheet, where "R46" suffix explicitly denotes the 4.63V variant within the MAX6378 series.

Does MAX6378UR46+T require an external pull-up resistor on its OUT pin?

No, MAX6378UR46+T does not require an external pull-up resistor because it features a push-pull output stage. The OUT pin actively drives low when VCC falls below 4.63V and actively drives high when VCC is above threshold - unlike open-drain variants such as MAX6380UR46+T which do require pull-up.

Can MAX6378UR46+T operate reliably at VCC = 1.5V?

Yes, MAX6378UR46+T guarantees correct output logic state down to VCC = 1V, per the datasheet's Absolute Maximum Ratings and Electrical Characteristics tables. At 1.5V, the device remains fully functional and will assert OUT low if VCC drops below the 4.63V threshold - though such a condition implies measurement error unless VCC is externally scaled.

What is the maximum transient duration that MAX6378UR46+T can ignore at 30mV overdrive?

At 30mV overdrive (i.e., VTH − VCC = 30mV), MAX6378UR46+T ignores transients up to 140µs, as shown in Figure MAX6375-04 ("Maximum Transient Duration vs. Threshold Overdrive"). This immunity prevents false resets caused by brief supply dips during switching regulator cross-regulation or ESD events.

Is MAX6378UR46+T pin-compatible with other devices in the MAX6375–MAX6380 family?

Yes, MAX6378UR46+T shares identical SOT23-3 pinout (GND, OUT, VCC) with all UR-suffix variants in the MAX6375–MAX6380 family, including MAX6375UR22+T through MAX6380UR46+T. This allows direct substitution within the same threshold group when changing reset voltage requirements, provided output logic polarity matches (all MAX6378 variants are active-low push-pull).