Analog Devices Inc./Maxim Integrated MAX16020LTET+T

Overview

MAX16020LTET+T from Maxim Integrated is a low-power microprocessor supervisory circuit with integrated battery-backup switchover, chip-enable (CE) gating, and power-fail monitoring. It monitors 3.0V systems (fixed 3.08V reset threshold), provides 145ms min reset timeout, 1.2µA supply current, and 1.5ns CEIN-to-CEOUT propagation delay. Used in RTC and SRAM backup circuits where brownout write protection and seamless VCC-to-battery handover are critical.

For engineers reviewing the MAX16020LTET+T datasheet, MAX16020LTET+T pinout, MAX16020LTET+T application, or MAX16020LTET+T equivalent, key selection criteria include its 16-pin TQFN package, push-pull RESET output, battery-OK/battery-on indicators, watchdog timer (1.2s typ), and CE gating with 12µs hold time during reset assertion.

Technical Context

The MAX16020LTET+T implements a dual-path power switch: VCC connects to OUT during normal operation; when VCC falls below 3.08V and VBATT > VCC, it automatically routes BATT to OUT to sustain SRAM/RTC. Its internal CE gating logic disables CEIN-to-CEOUT conduction during reset, holding CEOUT low for 12µs if CEIN is low at reset assertion - preventing partial writes during brownout.

It integrates five independent supervisory functions: reset generation (with debounced MR input), watchdog timer (1.2s timeout), power-fail comparator (0.590V threshold, 30mV hysteresis), low-line warning (LL, 2.5% above reset threshold), and battery health monitoring (BATTOK at 2.6V, BATT_TEST pulse every 24h). All operate across –40°C to +85°C with UL® IEC 60950-1 certification.

Key Specifications

Pinout & Package

MAX16020LTET+T is housed in a 16-pin 4mm × 4mm TQFN-EP package with exposed pad (EP) connected internally to GND. Thermal resistance θJA = 40°C/W supports operation up to +85°C ambient without heatsinking.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar microprocessor supervisory applications.

Compared with MAX16020LTET+T, MAX16021LTET+T adds flexibility for reset polarity without changing PCB layout, while TPS3808G33DBVR reduces cost and complexity only when battery management and CE protection are implemented elsewhere in the system.

Availability

MAX16020LTET+T is available at Aetrix Electronics and suitable for industrial control panels, GPS systems, set-top boxes, and point-of-sale terminals requiring stable component supply, long-term lifecycle support, and certified safety compliance.

Supply support for MAX16020LTET+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, mixed-signal, and power management ICs for demanding industrial, automotive, and communications applications.

The MAX160xx family targets µP-based systems needing consolidated supervision: reset, battery backup, CE gating, and power-fail detection - all in one small package with ultra-low quiescent current.

FAQ

What is the reset threshold voltage for MAX16020LTET+T?

The MAX16020LTET+T has a fixed reset threshold of 3.08V (typical), with a guaranteed range of 2.991V to 3.239V per Table 1b. This value is factory-trimmed and applies across the full –40°C to +85°C operating temperature range, with ±0.5% typical drift over temperature.

Does MAX16020LTET+T support both VCC and battery power sources simultaneously?

Yes - MAX16020LTET+T automatically switches OUT between VCC and BATT based on real-time conditions: OUT connects to VCC when VCC > VBATT and VCC > 3.08V; it connects to BATT only when VCC falls below 3.08V *and* VBATT > VCC. The device does not allow simultaneous sourcing from both rails.

How does the CE gating function work in MAX16020LTET+T during a reset event?

In MAX16020LTET+T, CE gating disables the CEIN-to-CEOUT path when RESET asserts. If CEIN is low at reset assertion, CEOUT remains low for 12µs (typ) to complete any ongoing memory access; then CEOUT is actively pulled high to OUT. If CEIN is high, CEOUT stays high throughout reset.

What is the purpose of the BATT_TEST pin on MAX16020LTET+T?

The BATT_TEST pin on MAX16020LTET+T outputs a 1.3s open-drain low pulse every 24 hours to activate an external test load. This draws current from the backup battery, allowing the system to verify remaining capacity - if VBATT drops below 2.6V during the test, BATTOK deasserts to signal battery depletion.

Can MAX16020LTET+T be used without connecting the MR pin?

Yes - MAX16020LTET+T includes an internal 30kΩ pullup resistor on MR, so the pin may be left unconnected if manual reset is not required. No external components are needed; the device operates fully with only VCC, BATT, GND, and required bypass capacitors.