Analog Devices Inc./Maxim Integrated MAX793TESE

Overview

MAX793TESE from Maxim Integrated is a 3.3V microprocessor supervisory circuit with fixed 3.00V–3.15V reset threshold, backup-battery switchover (VBATT > VCC supported), active-low open-drain RESET output, and integrated watchdog timer (1.6s timeout). It monitors critical power rails in battery-backed embedded controllers and provides chip-enable gating with ≤7ns propagation delay to protect CMOS RAM during undervoltage events.

For engineers reviewing the MAX793TESE datasheet, MAX793TESE pinout, MAX793TESE application, or MAX793TESE equivalent, this page delivers verified specifications, validated pin functions, confirmed use cases in portable equipment and intelligent controllers, and two technically documented alternative parts for supply continuity planning.

Technical Context

The MAX793TESE implements a precision voltage comparator with 10mV typical hysteresis on its reset threshold (3.00V–3.15V, VCC falling), guaranteed reset assertion down to VCC = 1V, and battery-switching logic that transitions OUT from VCC to BATT when VCC falls below VSW (2.55V–2.68V). Its watchdog circuit requires WDI toggling every 1.6s to maintain WDO high; absence triggers a low-going fault signal.

It integrates a low-line early-warning comparator (LOWLINE) with 5–60mV hysteresis relative to VRST, a dedicated BATT OK output (VBOK = 2.00V min) for lithium battery status monitoring, and CE IN-to-CE OUT transmission gating with 46Ω on-resistance and <7ns propagation delay-enabling real-time protection of memory access paths during brownouts.

Key Specifications

Pinout & Package

MAX793TESE is housed in a 16-pin narrow SO package (SOIC-16, 3.9mm width), RoHS-compliant, with standard JEDEC MS-012AC footprint and 1.27mm pitch.

Key Features

Applications

Equivalent & Alternatives

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

Compared with MAX793TESE, MAX793TESA offers identical functionality in a through-hole package for easier validation, while MAX795TESE reduces footprint and cost by removing nonessential supervision features-making it viable only where simplified reset and backup control suffice.

Availability

MAX793TESE is available at Aetrix Electronics and suitable for battery-powered computers and controllers, embedded controllers, and critical µP power monitoring applications requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for MAX793TESE 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 management, sensing, and interface applications in industrial, automotive, and communications systems.

The MAX793 family targets 3.0V/3.3V microprocessor supervision with integrated battery switchover, watchdog, and memory protection-optimized for reliability-critical embedded systems where power integrity and data retention are non-negotiable.

FAQ

What is the reset threshold voltage range for MAX793TESE?

The MAX793TESE has a fixed reset threshold range of 3.00V to 3.15V (VCC falling), specified for 3.3V systems with ±5% supply tolerance. This ensures reset assertion occurs before the 3.3V rail drops below 3.0V, providing robust brownout protection. The threshold is factory-trimmed and does not require external resistors-unlike the adjustable MAX794 variant. MAX793TESE maintains this specification across its full operating temperature range (0°C to +70°C).

Does MAX793TESE support backup-battery switchover with VBATT > VCC?

Yes, MAX793TESE explicitly supports backup-battery voltages exceeding VCC-up to 6.0V-as confirmed in Absolute Maximum Ratings and Electrical Characteristics. When VCC falls below the battery switch threshold (2.55V–2.68V), OUT automatically connects to BATT, enabling use of standard 3.6V lithium batteries in 3.0V/3.3V systems. The internal p-channel MOSFET switch ensures low on-resistance (<160Ω at +25°C) and leakage <1µA, preserving battery life.

What is the function of the LOWLINE output on MAX793TESE?

The LOWLINE output on MAX793TESE is an active-low early-warning comparator that asserts when VCC falls to VLR (VRST − 5mV to −60mV). It provides programmable advance notification-typically 5–60mV below the reset threshold-to trigger non-maskable interrupts (NMI) for graceful system shutdown, data save, or I/O freeze before reset occurs. This feature is absent in the pin-compatible MAX795TESE, making LOWLINE a key differentiator for applications requiring predictive power-fail response.

Can MAX793TESE drive CMOS RAM directly during battery backup?

Yes, MAX793TESE's OUT pin is designed to directly power CMOS RAM during battery backup. When VCC collapses, OUT seamlessly switches from VCC to BATT (up to 3.6V), maintaining RAM voltage above retention threshold. The device guarantees OUT remains stable with ≤15mV hysteresis during switchover, and supports continuous load currents up to 75mA (with external PMOS via BATT ON) or 250µA (internal switch). This eliminates need for external regulators or diode-OR circuits in typical SRAM backup configurations.

How does the watchdog timer operate in MAX793TESE?

The MAX793TESE watchdog timer requires WDI toggling every 1.6s to keep WDO high; failure to do so causes WDO to go low, signaling a fault. WDO can be diode-OR'd to MR to generate an automatic 200ms reset pulse. The timer clears on any WDI edge (≥100ns wide) and remains disabled while RESET is asserted. Unlike some competitors, this watchdog cannot be disabled-ensuring continuous supervision. Its 1.6s timeout is production-tested and stable across temperature (±10% variation from −40°C to +85°C).