STMicroelectronics L6730TR

Overview

L6730TR from STMicroelectronics is an adjustable step-down controller with synchronous rectification for high-current buck converter designs. The IC drives external N-channel MOSFETs, supports a 1.8 V to 14 V input voltage range, operates from a 4.5 V to 14 V controller supply, regulates output voltage down to 0.6 V, and provides fixed-frequency voltage-mode control for compact low-voltage DC/DC power stages.

For engineers reviewing the L6730TR datasheet, L6730TR pinout, L6730TR application, or L6730TR equivalent, this controller is most relevant for high-density DC/DC modules, low-voltage distributed power rails, niPOL converters, DDR memory supplies, DDR bus termination supplies, and embedded high-current buck regulators requiring programmable 100 kHz to 1 MHz switching frequency, RDS(on)-based overcurrent sensing, pre-biased startup support, source / sink selection, and HTSSOP20 tape-and-reel assembly.

Technical Context

L6730TR uses fixed-frequency voltage-mode PWM control and drives a synchronous buck power stage through HGATE and LGATE. The controller supports 0% to 100% duty cycle, minimum on-time below 100 ns, selectable 0.6 V or 1.2 V internal reference, external voltage-reference input, and output regulation down to 0.6 V with ±0.8% reference accuracy over line voltage and temperature from 0°C to 125°C.

The device integrates predictive anti-cross-conduction gate-drive control, programmable high-side and low-side MOSFET RDS(on) overcurrent protection, selectable UVLO threshold for 5 V or 12 V bus operation, soft-start and inhibit, PGOOD with programmable delay, overvoltage protection with selectable latched or non-latched behavior, thermal shutdown, and synchronization capability with 180° phase shift for master/slave converter operation.

Key Specifications

Pinout & Package

L6730TR is supplied in an HTSSOP20 exposed-pad package. The 20-pin exposed-pad TSSOP format supports compact synchronous buck controller layouts by keeping gate-drive, phase-node, current-limit, oscillator, feedback, soft-start, synchronization, power-good, and supply pins accessible while improving board-level thermal transfer and grounding through the exposed pad.

Key Features

• Adjustable synchronous step-down controller for external N-channel MOSFET buck converter stages.
• 1.8 V to 14 V converter input range and 4.5 V to 14 V controller supply range.
• Output voltage adjustable down to 0.6 V with ±0.8% reference accuracy over line and temperature.
• Selectable 0.6 V or 1.2 V internal reference plus external voltage-reference input.
• Programmable 100 kHz to 1 MHz switching frequency with synchronization and 180° phase-shift capability.
• Minimum on-time below 100 ns and 0% to 100% duty-cycle operation for wide conversion-ratio support.
• Programmable high-side and low-side MOSFET RDS(on) overcurrent sensing without a dedicated sense resistor.
• Pre-biased startup support, selectable source / sink behavior after soft-start, PGOOD delay, OVP, UVLO, and thermal shutdown.
• HTSSOP20 exposed-pad package supplied in tape-and-reel format for automated SMT production.

Applications

Equivalent & Alternatives

When evaluating L6730TR equivalent devices, engineers should compare package, packing format, source / sink behavior, overcurrent response mode, switching-frequency range, reference options, MOSFET gate-drive requirements, UVLO setting, PGOOD delay, pre-biased startup behavior, and whether the existing PCB uses the L6730 HTSSOP20 pinout.

Compared with L6730, L6730TR keeps the same controller architecture, pinout, HTSSOP20 package, and electrical function, with the main difference being tape-and-reel logistics. L6730TR vs L6730BTR selection depends on whether the converter design needs the L6730 source / sink selection behavior or the L6730B constant-current / hiccup overcurrent-response option.

Quality

L6730TR should be sourced as original STMicroelectronics components through traceable and controlled supply channels. Quality verification procedures may include HTSSOP20 exposed-pad package inspection, top-mark validation, tape-and-reel label review, solderability testing, exposed-pad inspection, VCC and VCCDR continuity checks, HGATE / LGATE driver-function testing, oscillator-frequency verification, PGOOD timing inspection, current-limit threshold review, and incoming inspection according to synchronous buck converter production requirements.

Availability

L6730TR is available at Aetrix Electronics and suitable for high-density DC/DC modules, low-voltage distributed power rails, niPOL converters, DDR memory supplies, DDR bus termination rails, and embedded high-current buck regulators requiring stable component supply and repeatable production support.

Supply support may include scheduled delivery planning, volume procurement support, BOM continuity assistance, traceable sourcing management, and long-term availability support for power-supply manufacturers, industrial equipment builders, computing hardware developers, repair groups, contract manufacturers, and legacy product owners using ST synchronous buck controller designs.

For production deployment, confirming the HTSSOP20 exposed-pad footprint, tape-and-reel format, input-voltage range, MOSFET gate-drive requirement, oscillator setting, compensation network, RDS(on) current-limit design, source / sink selection, protection-mode network, thermal requirements, and sourcing continuity helps reduce procurement risk and improve manufacturing stability.

Manufacturer

STMicroelectronics supplies power-management ICs, synchronous buck controllers, converters, microcontrollers, sensors, RF devices, protection products, and discrete semiconductors for industrial, automotive, consumer, communication, and embedded applications. L6730TR belongs to ST's power-management controller portfolio for high-current synchronous step-down conversion and low-voltage point-of-load power systems.

FAQ

What is L6730TR used for?

L6730TR is used to control high-current synchronous buck converters in high-density DC/DC modules, distributed point-of-load supplies, niPOL converters, DDR memory supplies, and DDR bus termination rails. It drives external N-channel MOSFETs and provides programmable frequency, soft-start, overcurrent protection, power-good monitoring, and low-voltage output regulation.

What input and output voltage ranges does L6730TR support?

L6730TR supports a converter input voltage range from 1.8 V to 14 V and a controller supply range from 4.5 V to 14 V. The regulated output voltage can be adjusted down to 0.6 V using the feedback and reference system, making the IC suitable for low-voltage core, memory, and termination rail applications.

How is the switching frequency set on L6730TR?

L6730TR uses the OSC pin to program the switching frequency from 100 kHz to 1 MHz. Frequency selection affects inductor size, switching loss, output ripple, transient response, MOSFET dissipation, and EMI behavior, so the oscillator setting should be chosen together with the external power-stage design.

How does L6730TR implement overcurrent protection?

L6730TR implements programmable high-side and low-side overcurrent protection using the RDS(on) of the external MOSFETs. OCH sets the high-side peak current limit, OCL sets the low-side current-limit behavior, and PHASE provides the switching-node reference. This approach avoids a dedicated sense resistor but requires careful MOSFET, layout, and temperature-margin selection.

What package is used by L6730TR?

L6730TR uses an HTSSOP20 exposed-pad package supplied in tape-and-reel format. The package provides 20 pins for feedback, compensation, soft-start, oscillator, synchronization, PGOOD, protection configuration, gate-drive outputs, bootstrap supply, current-limit sensing, and controller supply connections.

What is the difference between L6730TR and L6730?

L6730TR and L6730 use the same L6730 controller function, HTSSOP20 package, and electrical architecture. The difference is packaging logistics: L6730TR is supplied in tape-and-reel format for automated SMT assembly, while L6730 is supplied in tube packaging for tube-fed or lower-volume handling.

What is the difference between L6730TR and L6730BTR?

L6730TR and L6730BTR are related ST synchronous step-down controller options in the HTSSOP20 package, but the multifunction protection pin differs. L6730TR uses SINK/OVP/UVLO behavior for source / sink selection and protection configuration, while L6730BTR uses CC/OVP/UVLO behavior for selectable constant-current or hiccup overcurrent response after soft-start.

Can L6730TR start into a pre-biased output rail?

Yes. L6730TR includes pre-biased startup capability, which is useful when the output rail may already hold voltage before the controller starts. This behavior is important in DDR, multi-rail, and redundant power systems where uncontrolled sink current during startup could disturb the existing rail voltage.