Analog Devices Inc. LTC3823IGN#TRPBF

Overview

LTC3823IGN#TRPBF from Analog Devices (formerly Linear Technology) is a synchronous step-down DC/DC controller with true remote differential output sensing, output voltage tracking, and PLL-based external clock synchronization. It delivers 0.6V to 3.3V outputs (with remote sense) from 4.5V–36V input, supports ≤100ns minimum on-time, ±0.67% reference accuracy, and operates up to 90% duty cycle at 200kHz - ideal for high-efficiency server and ASIC power rails.

For engineers reviewing the LTC3823IGN#TRPBF datasheet, LTC3823IGN#TRPBF pinout, LTC3823IGN#TRPBF application, or LTC3823IGN#TRPBF equivalent, key selection criteria include its No RSENSE™ valley current mode control, programmable current limit via VRNG, differential remote sensing architecture, and dual N-channel MOSFET driver capability with <20ns rise/fall times.

Technical Context

The LTC3823IGN#TRPBF implements constant on-time, valley current mode control without requiring a sense resistor - enabling ultra-low duty cycles down to <100ns. Its internal phase-locked loop synchronizes switching frequency to an external clock while maintaining stable regulation across wide VIN (4.5V–36V) and VOUT (0.6V–3.3V with remote sense) ranges.

True differential remote sensing uses dedicated VOUTSENSE+/VOUTSENSE– inputs feeding a precision amplifier (gain = 0.9965–1.0035 V/V, offset ≤2mV) to reject PCB trace IR drop. Output tracking is implemented via the TRACK/SS pin, supporting both master-slave sequencing and soft-start ramp control using a single external capacitor.

Key Specifications

Pinout & Package

Package: 28-Lead Plastic SSOP Narrow (GN), 5mm × 5mm body, exposed pad not present. Thermal resistance θJA = 80°C/W.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous step-down controller applications.

Compared with LTC3855IGN#TRPBF and MP2918GL-Z, the LTC3823IGN#TRPBF uniquely combines differential remote sensing, output tracking, and PLL synchronization in a single 28-pin SSOP package - making it the only option for high-accuracy, multi-rail server and test equipment power systems requiring coordinated startup and low-noise operation.

Availability

LTC3823IGN#TRPBF is available at Aetrix Electronics and suitable for server power supplies, ASIC bias rails, and industrial distributed power systems requiring stable component supply, long-term lifecycle support, and guaranteed traceable sourcing.

Supply support for LTC3823IGN#TRPBF 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

Analog Devices acquired Linear Technology in 2017 and maintains full product continuity, technical documentation, and manufacturing for legacy Linear power ICs including the LTC3823 series.

The LTC3823IGN#TRPBF belongs to Linear's high-performance synchronous buck controller family, designed specifically for demanding digital power applications in servers, networking gear, and test instrumentation where precision regulation, sequencing, and EMI control are critical.

FAQ

What is the minimum achievable output voltage with LTC3823IGN#TRPBF?

The LTC3823IGN#TRPBF features a ±0.67% accurate 0.6V internal reference, enabling stable regulation down to exactly 0.6V. When used with external resistor dividers, the output can be set lower only if the feedback network introduces gain - but the controller itself does not support sub-0.6V regulation. All performance specifications, including line/load regulation and remote sensing accuracy, are guaranteed starting at 0.6V.

Does LTC3823IGN#TRPBF require an external sense resistor?

No - the LTC3823IGN#TRPBF implements Linear's No RSENSE™ architecture and can use the bottom MOSFET's RDS(ON) as the current sense element by connecting SENSE+ to SW and SENSE– to PGND. A discrete sense resistor is optional and only needed when precise, temperature-stable current limiting is required beyond what MOSFET RDS(ON) variation allows.

How does the TRACK/SS pin function in master-slave configurations?

In master configuration, the TRACK/SS pin accepts a capacitor to ground to define soft-start ramp rate. In slave configuration, the LTC3823IGN#TRPBF reproduces the master's VFB voltage via an external resistive divider applied to TRACK/SS - enabling precise voltage tracking and monotonic sequencing. The internal 1.7μA soft-start current charges the pin during startup unless Z1/SSENABLE is tied to INTVCC to disable it during tracking.

What thermal considerations apply to LTC3823IGN#TRPBF in SSOP package?

The LTC3823IGN#TRPBF in 28-lead SSOP has θJA = 80°C/W. At 85°C ambient and 1.5W dissipation, junction temperature reaches ~205°C - exceeding the 125°C absolute maximum. Therefore, thermal design must include adequate copper area, thermal vias to inner layers, and airflow. Derating is required above 60°C ambient for continuous full-load operation; consult the datasheet's power loss curves for exact limits.

Can LTC3823IGN#TRPBF synchronize to clocks other than its own switching frequency?

Yes - the LTC3823IGN#TRPBF's PLLIN pin accepts external clock signals from 100kHz to 1MHz. Its internal phase detector locks to any stable periodic signal within that range, regardless of the controller's nominal free-running frequency set by RON. This enables deterministic EMI reduction in systems with multiple switching regulators or noise-sensitive analog sections.