7 A boost in a 2.5 × 2 mm QFN — when you need it
The TPS61089RNRR is a 7 A, adjustable-output step-up (boost) converter from Texas Instruments, in an 11-pin VQFN-HR package measuring 2.5 × 2 mm. It accepts a 2.7 V to 12 V input rail and delivers a regulated output from 4.5 V up to 12.6 V, with synchronous rectification built in for efficiency. The switching frequency is programmable between 200 kHz and 2.2 MHz, letting the designer trade inductor size against switching losses.
Sizing the inductor and setting the switching frequency
The 200 kHz to 2.2 MHz switching range determines the inductor value. At 2.2 MHz the inductor can be small, saving board area.
Input voltage range and battery-powered fit
The 2.7 V minimum input lets this part run directly from a single-cell Li-Ion battery (3.0-4.2 V) through most of its discharge curve. The 12 V maximum input also suits 5 V or 12 V regulated rails, making it a universal boost stage for USB-C Power Delivery, portable speakers, or multi-cell battery packs. The adjustable output (4.5 V min) covers 5 V, 9 V, and 12 V rails — common targets for USB PD fixed-voltage profiles.
Package and layout — 11-VQFN-HR (2.5 × 2 mm)
The 11-VFQFN package has a 2.5 × 2 mm body. The small footprint means the surrounding passive components must be placed within a few mm to keep switching loops tight.