Analog Devices Inc. LT1302CN8-5#PBF

Overview

LT1302CN8-5#PBF from Analog Devices (formerly Linear Technology) is a fixed 5V micropower step-up DC/DC converter with integrated 2A NPN switch, operating from 2V–8V input and delivering up to 600mA at 5.05V in Burst Mode. It features 200µA quiescent current, logic-controlled shutdown (15µA), and low 310mV typical V_CE(SAT). Used in battery-powered portable instruments and PDAs requiring stable 5V rail from 2-cell alkaline or NiMH.

For engineers reviewing the LT1302CN8-5#PBF datasheet, LT1302CN8-5#PBF pinout, LT1302CN8-5#PBF application, or LT1302CN8-5#PBF equivalent, key selection criteria include input voltage range down to 2V, fixed 5V output tolerance (±4%), thermal shutdown protection, 8-pin PDIP package compatibility, and Burst Mode efficiency optimization at light loads.

Technical Context

The LT1302CN8-5#PBF implements dual-mode control: hysteretic Burst Mode for sub-100mA loads (enabling 200µA IQ) and current-mode regulation above ~100mA (ensuring fast line/load transient response). Its internal 2A NPN switch operates up to 400kHz with 75–95% duty cycle capability and 3.9µs minimum on-time.

Feedback is internally trimmed for 5.05V nominal output in Burst Mode, dropping to 4.97V in current mode. The SENSE pin (Pin 4) connects directly to an internal resistor divider; no external feedback resistors are required. Compensation is applied via RC network on VC pin (Pin 2) to stabilize the error amplifier loop.

Key Specifications

Pinout & Package

LT1302CN8-5#PBF uses an 8-lead plastic DIP (N8) package with 0.300" width and through-hole mounting. Thermal resistance θ_JA = 100°C/W (still air, 1oz copper).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar fixed-output step-up converter applications.

Compared with LT1302CS8-5#PBF, the LT1302CN8-5#PBF offers identical regulation but trades thermal performance for through-hole manufacturability; versus MAX756CPA+, it delivers 2× output current and higher input voltage tolerance but requires more careful compensation design.

Availability

LT1302CN8-5#PBF is available at Aetrix Electronics and suitable for portable instrumentation, handheld medical devices, and industrial data loggers requiring stable component supply with long-term obsolescence planning.

Supply support for LT1302CN8-5#PBF 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, inheriting its precision analog and power management portfolio. Linear pioneered high-performance switching regulators with integrated power switches.

The LT1302 family was designed for ultra-low-power portable systems needing efficient 5V generation from weak or multi-cell battery sources, emphasizing micropower operation, robust thermal behavior, and minimal external component count.

FAQ

What is the guaranteed minimum input voltage for reliable start-up of the LT1302CN8-5#PBF?

The LT1302CN8-5#PBF guarantees start-up and regulation from 2.0V input across the 0°C to 70°C temperature range. At 25°C, it can often start below 2.0V (e.g., 1.8V), but 2.0V is the tested minimum specification. This enables operation from deeply discharged 2-cell alkaline or NiMH batteries, extending usable runtime in portable equipment using the LT1302CN8-5#PBF.

Does the LT1302CN8-5#PBF require external feedback resistors to set its 5V output?

No. The LT1302CN8-5#PBF integrates precision feedback resistors internally, so Pin 4 (SENSE) connects directly to the internal 5.05V reference divider. Unlike the adjustable LT1302CN8, no external resistors are needed-reducing BOM cost, layout area, and potential drift. This fixed configuration is confirmed in the Electrical Characteristics table and block diagram for the LT1302CN8-5#PBF.

How does the LT1302CN8-5#PBF behave under no-load conditions?

Under no-load, the LT1302CN8-5#PBF enters Burst Mode, drawing just 200µA quiescent current. It delivers short, high-current pulses to maintain output voltage, resulting in low average power draw. Output ripple remains within 50mV_P-P with proper output capacitance. This behavior is intrinsic to the LT1302CN8-5#PBF's hysteretic comparator control and is verified in Figure TA02 and the Typical Performance Characteristics section.

Can the LT1302CN8-5#PBF be used in a 12V output application?

No-the LT1302CN8-5#PBF is factory-trimmed for fixed 5V output only. For 12V, use the adjustable LT1302CN8 with external feedback resistors, or select a dedicated 12V boost IC like the LT1302-12 variant. Attempting to force 12V with the LT1302CN8-5#PBF will result in overvoltage failure or unregulated operation, as its internal SENSE divider ratio is permanently set for 5.05V.

What is the maximum allowable output capacitor ESR for stable operation of the LT1302CN8-5#PBF?

The maximum recommended output capacitor ESR is 0.03Ω. Exceeding this value causes mode-hopping between Burst and current modes, leading to >500mV_P-P ripple and low-frequency oscillation (as shown in Figure F05). The LT1302CN8-5#PBF requires low-ESR capacitors such as AVX TPS polymer or Sanyo OS-CON types-standard aluminum electrolytics typically exceed this limit and destabilize regulation.