Dual-rail generation in a 3x3 mm footprint
The LT3487EDD#TRPBF packs two independent switching converters into a 10-lead 3x3 mm DFN package — one step-up switch rated 750 mA, the other rated 900 mA, both feeding adjustable outputs from a 2.3 V to 16 V input rail. The dual positive-and-negative output configuration means a single IC generates the bipolar rails needed for op-amp supplies, LCD bias, or sensor front-ends without a separate inverting stage.
Topology flexibility and output limits
The LT3487 supports boost, charge pump, and Cuk topologies — the charge pump mode generates a negative rail from a positive input without a magnetic component, while the Cuk topology provides a regulated inverted output with continuous input and output current. Output voltage adjusts from a 1.23 V reference up to 28 V maximum, so the same part serves a 3.3 V logic rail on one channel and a 24 V bias supply on the other. No synchronous rectifier means the external Schottky diode selection matters — a 1 A, 30 V Schottky with low forward drop keeps efficiency above 80% across most of the load range.
Sourcing and cross-reference reality
The single-output LT3579EFE#TRPBF delivers higher switch current (6 A) but lacks the second channel — it fits applications needing a single high-power rail, not the dual-rail requirement the LT3487 serves.