Texas Instruments UC3715DP

Overview

UC3715DP from Texas Instruments is a high-speed complementary switch FET driver IC designed for synchronous rectification and active clamp/reset circuits in DC-DC converters. It delivers 1-A source / 2-A sink power output and 0.5-A source / 1-A sink auxiliary output, with independently programmable 50–500 ns delays (T1/T2), 1-MHz switching capability, and TTL-compatible input. It enables zero-voltage switching in forward and flyback topologies.

For engineers reviewing the UC3715DP datasheet, UC3715DP pinout, UC3715DP application, or UC3715DP equivalent, key selection criteria include dual-output timing control, true-zero-voltage sensing on T1/T2 pins, ENBL-triggered 220-μA sleep mode, SOIC-16 package compatibility, and operation across 0°C to 70°C ambient.

Technical Context

The UC3715DP implements independent delay timers (T1 and T2) that control dead-time between AUX and PWR outputs using external resistors to ground - T1 sets AUX-to-PWR turn-on delay, T2 sets PWR-to-AUX turn-off delay. Each timer pin has internal 3-V nominal reference and ±2-mA current limiting, enabling both programmable delay and zero-voltage sensing modes.

Its logic architecture accepts a single PWM input: rising edge triggers immediate AUX activation and initiates T1 delay before PWR turn-on; falling edge triggers immediate PWR turn-off and initiates T2 delay before AUX turn-off. In sleep mode (ENBL ≤ 0.8 V), PWR output is actively held low while AUX enters high-impedance state.

Key Specifications

Pinout & Package

UC3715DP is housed in a 16-pin SOIC (D) package with 1.27-mm pitch, moisture sensitivity level 2-260°C/1 year, and RoHS-compliant green finish (Pb-free, no Sb/Br).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar complementary FET driver applications.

Compared with UC3715D, UC3715DP provides additional reference outputs and pin redundancy for robust layout; compared with UCC27201D, it offers unique T1/T2 delay and zero-voltage sensing - making UC3715DP irreplaceable for active clamp and ZVS-critical topologies.

Availability

UC3715DP is available at Aetrix Electronics and suitable for forward converters, active clamp flyback supplies, synchronous rectifier modules, and isolated gate driver interfaces requiring stable component supply and long-term industrial availability.

Supply support for UC3715DP 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 delivering analog, embedded processing, and connectivity solutions for industrial, automotive, and communications markets.

The UC3715DP belongs to TI's legacy complementary FET driver product line, engineered specifically for soft-switching power converter topologies requiring independent dead-time control and zero-voltage detection capability.

FAQ

What is the operating temperature range for the UC3715DP?

The UC3715DP is specified for operation from 0°C to 70°C ambient temperature. This commercial-grade range aligns with its target applications in telecom power supplies and industrial DC-DC modules where full industrial (–40°C to 85°C) rating is not required. The device's thermal design supports continuous 2-A sink current within this range when properly heatsinked and PCB-layout optimized.

How does the UC3715DP implement zero-voltage switching (ZVS) support?

The UC3715DP implements ZVS support through true zero-voltage sensing on its T1 and T2 pins: pulling either pin below ~2.5 V immediately activates the corresponding output (PWR or AUX), bypassing the programmed delay. This allows direct connection to resonant tank voltage nodes - enabling instantaneous switch turn-on when voltage crosses zero - a critical function for ZVS in LLC and active clamp topologies. The UC3715DP datasheet confirms this behavior in Figure 8 and the PIN DESCRIPTIONS section.

Can the UC3715DP drive both high-side and low-side N-channel MOSFETs in a synchronous rectifier?

Yes, the UC3715DP can drive both high-side and low-side N-channel MOSFETs in a synchronous rectifier configuration. Its PWR output delivers 1-A source / 2-A sink and AUX delivers 0.5-A source / 1-A sink - sufficient for typical 30–60 V secondary-side gate drive. However, high-side drive requires external level-shifting (e.g., charge pump or isolated supply), as UC3715DP lacks integrated high-side bootstrap or level-shift circuitry. Figure 11 in the UC3715DP datasheet demonstrates this exact implementation.

What is the purpose of the duplicate VREF pins (Pin 9 and Pin 14) on the UC3715DP?

The UC3715DP features two VREF pins (9 and 14) providing identical 3-V internal reference outputs. This duplication improves layout flexibility and current capacity: designers may use one pin for timing resistor biasing and the other for auxiliary circuitry (e.g., comparator reference or ADC scaling), or parallel them to supply up to 10 mA total while maintaining regulation. Unlike UC3715D (SOIC-8), the UC3715DP's SOIC-16 package enables this redundancy to support complex power stage monitoring without external references.

Is the UC3715DP pin-compatible with earlier UCx715 variants like UC2715DP?

No, the UC3715DP is not pin-compatible with UC2715DP. Although both are SOIC-16 packages, their pin functions differ significantly: UC2715DP supports –40°C to 85°C operation and maps certain pins (e.g., ENABLE) differently, while UC3715DP is rated for 0°C to 70°C and assigns VREF, BIAS, and redundant pins per SLUS170B Rev B. The datasheet explicitly lists UC3715DP as obsolete in the PACKAGE OPTION ADDENDUM, confirming distinct qualification and pinout - substitution requires schematic and layout revision.