BT29 Series
Clean-and-Simple, Optocoupler-Enhanced Boost Regulators
BT29 Series overview
BT29 is a series of low-noise, switching-free optocoupler-enhanced linear boost voltage regulators that use Polaris Semiconductor’s patented circuit topology. The devices consist of a high-current MIC29152 LDO co-packaged with Polaris Semiconductor high-efficiency optocoupler chips. This offers high PSRR, low ground current, and high output-current performance combined with efficient, switching-free boost capability.
The BT29 series has been designed for up to 5 V output and is configured for 3–5 V input voltages. During optocoupler-enhanced operation, the LDO injects current into the optocoupler’s LED, which transfers photons to the PV device. In turn, the PV device steps up the input voltage, which is then regulated by the LDO’s feedback circuit. The result is an efficient, simple, and switching-free boost regulator.
Base LDO: MIC29152. Every device can also be operated as a conventional LDO by shorting two pins.
Device configurations
| Device | Nominal Vout range | Iin @ Iout = 0.1 A | Min Vin @ Iout = 0.1 A | QFN package |
|---|---|---|---|---|
| BT291D18M | Von – 5 V | 240 mA | 3.1 V (M) | QFN-28 · 6×6×0.8 mm |
- Iin is typical input current after device turn-on.
- Von denotes the turn-on voltage: the minimum input at which the boosted output regulates (defined in the ELR white paper, Eq. 1).
- An additional boost configuration — BT291D50M, the “Tiny Boost” of PSAN001 (also featured in PSAN002), with an adjustable output up to 5 V — is documented in the application notes and BT29 spotlight and is available for sampling; contact us for specifications. Earlier literature refers to this part as BT291D50H — same device.
Applications
- Clean Analog Supply Requirements
- Post-Switching Power Supply
- Rad-Tolerant Space Power Supply
- Battery-Powered Systems
Technical documentation
Application notes, white papers, and spotlights covering the BT29 series.
Datasheets and SPICE models ship with a sample request — or email info@polarissemiconductor.com.
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