Renesas M5295AFP#DF0R

Overview

M5295AFP#DF0R from Renesas Electronics is a dual-voltage watchdog timer IC designed for system reset supervision in +5 V microcomputer applications. It provides two independent voltage detection thresholds (VTH1 = 4.25 V, VTH2(L) = 4.6 V), a programmable watchdog timer (tWD = 0.5–1.7 ms), low quiescent current (0.8 mA typ), and dual open-drain reset outputs (RST1, RST2) for power-on and fault recovery sequencing.

For engineers reviewing the M5295AFP#DF0R datasheet, M5295AFP#DF0R pinout, M5295AFP#DF0R application, or M5295AFP#DF0R equivalent, this device supports critical reset timing control, adjustable supply monitoring, and watchdog timeout validation in industrial embedded systems where deterministic power-up behavior and runtime fault detection are required.

Technical Context

The M5295AFP#DF0R integrates a precision reference voltage generator (1.24 V), dual comparators with hysteresis, a charge/discharge timing circuit driven by external RC components on the TC pin, and two independent reset latches. Its WD input accepts capacitor-coupled clock pulses to reset the watchdog timer before timeout.

Reset generation is triggered by three distinct conditions: VCC falling below VTH1 (4.25 V), VCC dropping below VTH2(L) (4.6 V) with 100 mV hysteresis, or absence of valid WD pulses causing TC pin voltage to oscillate between VTH3(L) = 2.0 V and VTH3(H) = 4.0 V - resulting in RST1 toggling until normal operation resumes.

Key Specifications

Pinout & Package

Package: PRSP0008DE-C - 8-pin SOP (Small Outline Package), 4.4 mm × 4.85 mm body, 1.27 mm pitch, surface-mount, mass 0.1 g.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar watchdog timer applications.

Compared with MAX6326US29D3+T and TPS3823-33DBVR, the M5295AFP#DF0R uniquely delivers dual adjustable voltage thresholds, fully programmable watchdog timing via external RC, and two independent open-drain reset outputs - enabling complex power sequencing and adaptive fault recovery in multi-rail embedded systems.

Availability

M5295AFP#DF0R is available at Aetrix Electronics and suitable for industrial automation, medical diagnostics, and telecom infrastructure requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for M5295AFP#DF0R 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

Renesas Electronics Corporation is a global semiconductor leader specializing in microcontrollers, analog, power, and timing solutions for industrial, automotive, and enterprise applications.

The M5295AFP#DF0R belongs to Renesas' legacy watchdog timer product line, engineered specifically for robust system-level reset supervision in microcomputer-based equipment operating under variable supply and thermal conditions.

FAQ

What is the function of the TC pin on the M5295AFP#DF0R?

The TC pin on the M5295AFP#DF0R serves as the internal timing capacitor node that controls both the watchdog timeout (tWD) and reset timer durations. Its voltage ramps up and down based on external R1 and C components; crossing VTH3(H) = 4.0 V and VTH3(L) = 2.0 V triggers RST1 assertion or release. This pin enables precise, user-adjustable timing without requiring internal oscillator calibration - a key feature distinguishing the M5295AFP#DF0R from fixed-timer alternatives.

Can the M5295AFP#DF0R monitor two different supply voltages simultaneously?

Yes, the M5295AFP#DF0R can monitor two distinct supply rails using its dual detection architecture. VTH1 (pin ADJ1) configures detection of the primary 5 V rail (e.g., 4.25 V threshold), while VTH2(L) (pin ADJ2) sets a higher threshold (e.g., 4.6 V) for a secondary or backup supply. Each threshold operates independently with dedicated hysteresis and drives separate open-drain outputs (RST1 and RST2), allowing the M5295AFP#DF0R to manage complex power sequencing in multi-source systems.

What is the maximum recommended value for R1 when configuring the watchdog timer on the M5295AFP#DF0R?

The maximum recommended value for R1 when configuring the watchdog timer on the M5295AFP#DF0R is 30 kΩ, as specified in the "Notice for Use" section of the datasheet. Exceeding this value risks violating the 1.1 s upper limit for tWD and may cause unreliable watchdog timeout behavior due to leakage current effects or noise susceptibility. For stable operation across –20 °C to +75 °C, R1 should remain within 10 kΩ to 30 kΩ, paired with C values from 0.01 µF to 10 µF per the tWD = 1.1·C·R1 formula.

Does the M5295AFP#DF0R require external capacitors on ADJ1 and ADJ2 pins?

No, the M5295AFP#DF0R does not require external capacitors on ADJ1 or ADJ2 pins. These pins are high-impedance reference inputs connected internally to precision 1.24 V bandgap references; they interface solely with resistor dividers to set VTH1 and VTH2(L). However, the datasheet recommends adding ~1000 pF capacitors from ADJ1 and ADJ2 to GND if noise-induced malfunction occurs - this is a mitigation step, not a functional requirement for baseline operation of the M5295AFP#DF0R.

How does the M5295AFP#DF0R handle supply voltage transients near its detection thresholds?

The M5295AFP#DF0R handles supply voltage transients near detection thresholds using built-in hysteresis: VTH2(L) has a fixed 100 mV hysteresis (VTH2(H) − VTH2(L) = 0.1 V), preventing output chatter during slow or noisy VCC ramps. VTH1 lacks explicit hysteresis in specification but exhibits inherent stability due to internal comparator design and RC filtering on the ADJ pins. For worst-case transient immunity, the M5295AFP#DF0R relies on external RC networks on ADJ1/ADJ2 (≤15 kΩ total resistance) and optional 1000 pF bypass caps - ensuring clean threshold crossing even under EMI or load-switching events.