Texas Instruments TL7700CPWRE4

Overview

TL7700CPWRE4 from Texas Instruments is a bipolar supply-voltage supervisor IC used for power-on reset generation in microcontroller, DSP, and FPGA systems. It features an adjustable 500 mV (±1%) internal sense threshold, 1.8 V to 40 V wide supply range, –40°C to 85°C operating temperature, and open-collector RESET output with 5 mA sink capability - deployed in industrial control systems and notebook power monitoring.

For engineers reviewing the TL7700CPWRE4 datasheet, TL7700CPWRE4 pinout, TL7700CPWRE4 application, or TL7700CPWRE4 equivalent, key selection considerations include its externally adjustable sense voltage via resistor dividers, programmable hysteresis, timing-capacitor–controlled reset pulse duration (0.5–1.5 ms typical), and compatibility with battery, AC-line, and automotive supply rails.

Technical Context

The TL7700CPWRE4 integrates a precision 1.5 V temperature-compensated reference, fast comparator, constant-current timing generator (ICT = 15 µA typ), and npn open-collector output driver. Its SENSE input compares external divided voltage against a stable 500 mV reference, while CT terminal controls reset pulse width via capacitor charging.

Operation relies on two independent analog paths: one for threshold detection (Vs = 500 mV ±5 mV at 25°C, ±10 mV over full temperature range) and another for hysteresis setting (Is = 2.5 µA ±0.5 µA), both derived from the same internal reference to minimize drift. The device remains functional down to 1.8 V supply, enabling use in low-voltage embedded systems.

Key Specifications

Pinout & Package

TSSOP-8 (PW) package: 3.00 mm × 4.40 mm body, 0.65 mm pitch, exposed pad not present, RoHS-compliant NiPdAu lead finish, MSL Level-1.

Key Features

Applications

Equivalent & Alternatives

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

Compared with TL7700CPWRE4, TPS3808G12DBVR offers lower quiescent current but forfeits adjustability and hysteresis flexibility, while MAX6816EUT+T provides robust ESD tolerance and push-pull drive but locks users to a single voltage threshold - making TL7700CPWRE4 uniquely suited for multi-rail, noise-prone, or legacy-bipolar designs requiring field-programmable reset points.

Availability

TL7700CPWRE4 is available at Aetrix Electronics and suitable for industrial control systems, FPGA configuration sequencing, and automotive body electronics requiring stable component supply across extended temperature and voltage ranges.

Supply support for TL7700CPWRE4 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 company headquartered in Dallas, Texas, designing and manufacturing analog, embedded processing, and logic products for industrial, automotive, and communications markets.

The TL7700CPWRE4 belongs to TI's legacy bipolar supervisor product line, engineered specifically for robust, wide-input-voltage reset control in environments where reliability under voltage transients and temperature extremes is critical.

FAQ

What is the function of the CT pin on the TL7700CPWRE4?

The CT pin on the TL7700CPWRE4 connects to an internal 15 µA constant-current source that charges an external timing capacitor. This charging determines the duration of the active-low RESET pulse (tpo ≈ Ct × 10⁵ s). When CT is left open, the TL7700CPWRE4 operates as an adjustable-threshold comparator without timed reset. Driving CT with an external switch or FET enables programmable reset timing or manual reset initiation.

Can the TL7700CPWRE4 monitor a 3.3 V supply directly?

Yes, the TL7700CPWRE4 can monitor a 3.3 V supply directly using a resistor divider on the SENSE pin. With a typical internal sense threshold of 500 mV, a 6.6:1 resistor ratio (e.g., R₁ = 66 kΩ, R₂ = 10 kΩ) sets the trip point to 3.3 V. Hysteresis is added by selecting R₁ to yield Vhys = Is × R₁ (e.g., 2.5 µA × 66 kΩ = 165 mV), ensuring stable operation despite supply ripple.

What is the maximum sink current capability of the TL7700CPWRE4 RESET output?

The TL7700CPWRE4 RESET output is an npn open-collector transistor rated for 5 mA maximum sink current (IOL) with VOL ≤ 0.8 V at IOL = 3 mA. At 25°C, it typically sinks 3 mA with VOL < 0.4 V. Exceeding 5 mA risks exceeding absolute maximum ratings and may degrade long-term reliability; external buffer transistors are recommended for loads >5 mA.

Does the TL7700CPWRE4 require a decoupling capacitor on VCC?

Yes, a 0.1 µF ceramic decoupling capacitor is recommended between VCC and GND, placed as close as possible to the TL7700CPWRE4 pins. This minimizes supply noise coupling into the internal reference and comparator, preventing false resets during transient events. For high-noise environments (e.g., motor drives), a parallel 10 µF tantalum capacitor further stabilizes the supply rail.

How does temperature affect the sense voltage accuracy of the TL7700CPWRE4?

The TL7700CPWRE4 sense voltage (Vs) varies from 490 mV to 510 mV across –40°C to +85°C, representing ±2% total variation relative to nominal 500 mV. This drift is fully specified and compensated by the internal 1.5 V temperature-stable reference. Designers must account for this range when calculating resistor-divider ratios to ensure trip-point margin remains sufficient at temperature extremes.