Texas Instruments TL7770-5CDW

Overview

TL7770-5CDW from Texas Instruments is a dual-channel power-supply supervisor IC designed for microcomputer/microprocessor reset control, featuring independent 5-V and programmable undervoltage sensing (1VSU/2VSU), overvoltage detection at VSO (2.48–2.68 V threshold), true/complementary RESET outputs, and 250-mA peak SCR gate drive capability - used in industrial power-up sequencing and fault-safe power monitoring.

For engineers reviewing the TL7770-5CDW datasheet, TL7770-5CDW pinout, TL7770-5CDW application, or TL7770-5CDW equivalent, this page delivers verified functional identity, exact dual-threshold supervision behavior, timing capacitor-based pulse duration control, SCR-triggering logic, and temperature-compensated voltage reference performance across 0°C to 70°C operation.

Technical Context

The TL7770-5CDW implements two independent voltage-monitoring channels: Channel 1 uses fixed 5-V undervoltage threshold (VIT+ = 4.46–4.64 V) at 1VSU, while Channel 2 supports programmable undervoltage sensing (VIT– = 1.47–1.53 V) at 2VSU. Both channels share a common 2.48–2.68 V overvoltage threshold at VSO terminals.

Reset assertion occurs when VCC exceeds 1 V (Vres = 0.8–1.0 V), followed by time-delay latching via external CT capacitor; propagation delays are 270–500 ns (tPLH/tPHL), with 150 ns minimum RESIN pulse width and 100 ns minimum VSU glitch rejection window.

Key Specifications

Pinout & Package

TL7770-5CDW is housed in a 16-pin SOIC (DW) package, 7.5 mm × 10.3 mm body size, 1.27 mm lead pitch, 2.65 mm max height, RoHS-compliant NIPDAU finish, MSL Level-1 (260°C reflow).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual-supply supervision applications.

Compared with TPS3823-01DBVR and MAX6822UT29D3+, the TL7770-5CDW uniquely combines dual independent thresholds (one fixed, one programmable), integrated SCR gate drive for hardware-level fault isolation, and externally adjustable reset timing - making it irreplaceable in safety-critical crowbar-protected systems.

Availability

TL7770-5CDW is available at Aetrix Electronics and suitable for industrial PLC power sequencing, automotive BCM fault management, and medical infusion pump controller applications requiring stable component supply and long-term lifecycle support.

Supply support for TL7770-5CDW 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

Texas Instruments is a global semiconductor leader founded in 1930, specializing in analog, embedded processing, and power management ICs with broad industrial, automotive, and communications portfolio coverage.

The TL7770 series belongs to TI's legacy power-supervisor product line, engineered specifically for robust, hardware-based reset control and overvoltage fault response in mission-critical embedded systems.

FAQ

What is the exact undervoltage threshold at 1VSU for TL7770-5CDW?

The TL7770-5CDW has a nominal undervoltage threshold of 4.46 V to 4.64 V at the 1VSU pin, specified across 0°C to 70°C ambient temperature. This fixed 5-V sensing point is factory-trimmed and temperature-compensated, ensuring ±2% accuracy without external calibration. The hysteresis is 15 mV, providing noise immunity against supply ripple. TL7770-5CDW does not require external resistors to set this threshold.

Can TL7770-5CDW monitor a 1.2-V supply rail?

No - TL7770-5CDW's 2VSU input is specified for programmable undervoltage detection down to 1.47–1.53 V only. It cannot reliably supervise a 1.2-V rail due to insufficient headroom below the minimum VIT– threshold. For sub-1.5-V monitoring, a dedicated low-voltage supervisor such as the TPS3808G12 is required. TL7770-5CDW's design envelope begins at 1.47 V on 2VSU.

How is reset pulse duration calculated for TL7770-5CDW?

Reset pulse duration (td) for TL7770-5CDW is calculated as td ≈ 20 × 10³ × C, where C is the timing capacitor value in farads connected to 1CT or 2CT. For example, a 10 µF capacitor yields ~200 ms. When VCC and VSU share a node, a series resistor RT (typically 10 kΩ) must be added between CT and 1CT to prevent timing error - TL7770-5CDW's internal timing circuitry assumes isolated CT biasing.

Does TL7770-5CDW support overvoltage detection above 12 V?

No - TL7770-5CDW's overvoltage sense input (VSO) has a fixed threshold of 2.48–2.68 V, independent of supply voltage. To detect overvoltage on higher rails (e.g., 12 V), external resistor dividers must scale the rail down to match the VSO threshold. The device itself does not support direct high-voltage sensing; its internal comparator operates only at the 2.5-V range. TL7770-5CDW's VSO pin accepts up to 18 V input but triggers only at ~2.5 V.

Is TL7770-5CDW pin-compatible with TL7770-12CDW?

Yes - TL7770-5CDW and TL7770-12CDW share identical DW package pinout, electrical interface, and timing behavior. The only difference is the factory-trimmed undervoltage threshold at 1VSU: 4.46–4.64 V for TL7770-5CDW versus 10.68–11.12 V for TL7770-12CDW. All other pins (including 2VSU, VSO, SCR DRIVE, RESET outputs) function identically, enabling drop-in replacement when adjusting for different main supply voltages.