Enhanced Linear Regulators

Products

Inductorless, switching-free DC regulation in buck and boost topologies. Pick by current, noise floor, or radiation rating — every part ships on an evaluation board, with datasheets and SPICE models on request.

Families

Four series, one architecture

Each family pairs a proven LDO core with Polaris PV-output optocouplers: pick the core that matches your constraint, keep the same switching-free architecture.

Selection table

Every orderable part, one table

All specifications from the published product table and series pages. Parts are under development; specifications are subject to change. Unknowns are marked TBD — never estimated.

Polaris Enhanced Linear Regulators — full parametric selection table
Part Topology VOUT (V) Max VIN (V) Min VIN (enhanced) Max IOUT (mA) PSRR @ 1 kHz (dB) RMS noise (µV) TID krad(Si) Package LDO core Docs
BK191D18V Buck 1.2 – 2 20 VOUT + 1.4 (L)
VOUT + 2.8 (M)
900 75 12 200 QFN-28 · 6 mm RH1965 Spotlight
BK291D18V Buck 1.2 – 2 26 VOUT + 1.4 (L)
VOUT + 2.8 (M)
1000 65 160 200 QFN-28 · 6 mm MIC29152 Spotlight
BK291D33L Buck 1.2 – 4 26 VOUT + 1.4 1000 65 245 200 QFN-32 · 7 mm MIC29152 Spotlight
BK291D33V Buck 1.2 – 4 26 VOUT + 2.8 (M)
VOUT + 5.5 (H)
1000 65 245 200 QFN-32 · 7 mm MIC29152 Spotlight
BK291D50E Buck 1.2 – 5 26 VOUT + 7.0 1000 65 350 200 QFN-32 · 7 mm MIC29152 Spotlight
BK301D18V Buck 0 – 2 15 VOUT + 1.4 (L)
VOUT + 2.8 (M)
500 >100 <1 200 QFN-28 · 6 mm LT3045 Spotlight
BK301D33L Buck 0 – 4 15 VOUT + 1.4 500 >100 <1 200 QFN-32 · 7 mm LT3045 Spotlight
BK301D33V Buck 0 – 4 15 VOUT + 2.8 (M)
VOUT + 5.5 (H)
500 >100 <1 200 QFN-32 · 7 mm LT3045 Spotlight
BK301D50H Buck 0 – 6 15 VOUT + 4.1 500 >100 <1 200 QFN-32 · 7 mm LT3045 Spotlight
BK300D50E Buck 0 – 5 15 VOUT + 7.0 500 >100 <1 200 QFN-32 · 7 mm LT3045 Spotlight
BT291D50M Boost up to 5 12 3.1 350 60 200 200 QFN-28 · 6 mm MIC29152 Spotlight
  1. All parts listed here are under development and device specifications are subject to change.
  2. Minimum input voltage applies in optocoupler-enhanced mode at Iout = 0.1 A. Every device can also operate as a conventional low-dropout linear regulator with lower VIN via the pin connections to the device.
  3. RMS output noise is specified over 10 Hz – 100 kHz.
  4. Part numbers ending in “V” select between two input-voltage ranges via board-level pin connections.
  5. TID ratings denote device-level radiation tolerance. The BK19’s RH1965 LDO core additionally carries QML-V radiation hardness assurance (200 krad(Si) at a 50 rad/s dose rate).
  6. For the boost part (BT291D50M), at input voltages above the 5 V output the device continues to regulate.
  7. All Polaris ELR parts can be easily paralleled for higher output currents, lower output noise and improved thermal dissipation. Example schematics, BoM and PCB layout guidelines are described in application note PSAN003.
Selection guide

Reading a Polaris part number

BK29
Series · BK buck / BT boost
1D
Device code
33
Output-voltage code
L
Input-voltage range

Output-voltage code (buck): 18 ⇒ outputs up to 2 V · 33 ⇒ up to 4 V · 50 ⇒ up to 5 V (up to 6 V on BK301D50H). Outputs are adjustable: BK19 and BK29 devices down to 1.2 V, BK30 devices down to 0 V — see the selection table for each part's exact range.

Input-voltage range: L lowest · M medium · H high · E extended — IDs ending in V select between two ranges via board-level pin connections. Every device also runs as a conventional LDO by shorting two pins ("LDO mode").

Boost (BT) parts share the same grammar but regulate up to 5 V — see the BT29 series page for output behavior.

Evaluation

Every part, on a board

All products are available on evaluation boards, ready to drop into your test setup. Request one with your samples.

Documentation

Datasheets & SPICE models

Full datasheets and SPICE models are available on request — ask with your sample request or talk to an engineer.

Custom

Don't see your spec?

We also offer custom configurations — different LDO cores, output ranges, and input windows. Tell us what you need.

Get started

Ready to design it in?

Request evaluation samples, detailed datasheets, and SPICE models — an engineer answers, not a sales funnel.