NXP Semiconductors TEA1998TS/1X

Overview

TEA1998TS from NXP Semiconductors is a GreenChip synchronous rectifier (SR) controller IC for flyback SMPS secondary-side rectification, featuring adaptive gate drive, drain-source differential sensing (−400 mV activation), 25 mV regulation voltage, and self-supply capability for low-voltage (≤4.7 V) or high-side SR configurations. It drives external MOSFETs in USB BC/QuickCharge adapters and low-output-voltage chargers.

For engineers reviewing the TEA1998TS datasheet, TEA1998TS pinout, TEA1998TS application, or TEA1998TS equivalent, key selection considerations include its TSOP6 package, 1.4 μs minimum on-time, 0.7 A source / 0.5 A sink gate drive, UVLO with active pull-down, and support for both standard and logic-level SR MOSFETs without auxiliary winding.

Technical Context

The TEA1998TS implements a dual-stage SR control architecture: a high-precision drain-source voltage comparator (Vreg(drv) = −25 mV typical) with blanking and regulation feedback, coupled with an adaptive gate driver that dynamically adjusts output to maintain optimal MOSFET conduction. Its SOI process enables robust operation up to 60 V drain sense input and −40 °C to +150 °C junction temperature.

Start-up is managed via dual-path capacitor charging-through DRAIN when XV < 4.7 V, or through XV with internal regulation when XV ≥ 4.7 V-enabling self-supply in high-side or sub-4.7 V output applications. The IC integrates energy-save mode with <250 μA no-load supply current and active gate pull-down (3.2 Ω typical) during UVLO or post-turn-off.

Key Specifications

Pinout & Package

TEA1998TS is housed in a plastic surface-mounted TSOP6 package (SOT457), measuring 3.1 mm × 2.7 mm × 1.1 mm, with 6 leads and JEDEC-standard thermal resistance (R_th(j-a) = 200 K/W).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous rectifier controller applications.

Compared with NCP4306DR2G and IRS11682PBF, the TEA1998TS uniquely supports high-side rectification and sub-4.7 V outputs without auxiliary windings, offers superior noise-immune Kelvin source sensing, and delivers tighter −25 mV V_DS regulation-critical for maximizing efficiency in USB PD and ultra-low-power adapters.

Availability

TEA1998TS is available at Aetrix Electronics and suitable for USB-C Power Delivery adapters, smartphone fast-charging wall adapters, and low-voltage battery chargers requiring stable component supply, consistent parametric performance, and long-term lifecycle support.

Supply support for TEA1998TS 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

NXP Semiconductors is a global semiconductor company headquartered in Eindhoven, Netherlands, specializing in secure connectivity solutions for automotive, industrial, and consumer applications.

The TEA1998TS belongs to NXP's GreenChip family of high-efficiency power conversion ICs, designed specifically to replace secondary-side rectifier diodes in flyback converters with intelligent synchronous rectification for energy-efficient AC-DC power supplies.

FAQ

What is the primary function of the TEA1998TS in a flyback power supply?

The TEA1998TS serves as a dedicated synchronous rectifier controller on the secondary side of flyback converters. It senses the drain-source voltage of an external MOSFET and drives its gate to replace the conventional rectifier diode, thereby reducing conduction losses. In the TEA1998TS, this is achieved via adaptive gate drive with −25 mV regulation, enabling high efficiency across full load range-including light-load conditions where diode losses dominate.

How does the TEA1998TS achieve self-supply in high-side rectification configurations?

The TEA1998TS achieves self-supply in high-side rectification by charging the external capacitor on the CAP pin through the DRAIN pin when the XV pin voltage is below 4.7 V. During positive drain voltage transitions, current flows into CAP via internal circuitry, eliminating the need for an auxiliary winding. This capability is confirmed in Section 8.2 and Figure 9 of the TEA1998TS datasheet and is intrinsic to the TEA1998TS design.

What is the significance of the SOURCE pin on the TEA1998TS?

The SOURCE pin on the TEA1998TS provides a dedicated Kelvin connection for sensing the SR MOSFET source potential, decoupling measurement from high-dI/dt power ground paths. This minimizes voltage errors caused by parasitic inductance, ensuring accurate −25 mV V_DS regulation. As specified in Section 8.6, the SOURCE pin must be routed directly to the MOSFET source terminal-not shared with power ground-to preserve regulation fidelity in the TEA1998TS.

Can the TEA1998TS drive both standard and logic-level SR MOSFETs?

Yes, the TEA1998TS supports both standard and logic-level SR MOSFETs. When the XV pin is grounded, the gate driver regulates to ~10 V, sufficient for standard MOSFETs. When XV is connected to the output (≥4.7 V), the driver regulates to the XV voltage-e.g., 4.9 V at 5 V output-enabling full enhancement of logic-level devices. This dual-mode operation is explicitly documented in Section 8.5 and Table 6 of the TEA1998TS datasheet.

What protection features are integrated into the TEA1998TS?

The TEA1998TS integrates UnderVoltage LockOut (UVLO) with active gate pull-down (3.2 Ω typical), overvoltage clamp on the DRAIN pin (60 V max), and built-in minimum on-time (1.4 μs) to prevent false turn-off from ringing. Its SOI process also provides inherent latch-up immunity and extended temperature operation (−40 °C to +150 °C). These protections are defined in Sections 2.3, 9, and 10 of the TEA1998TS product data sheet.