Calif.—Semtech Corp. announced a new boost converter platform offering what it
claims is the industry’s smallest step-up regulators for low-voltage
SC120, SC121 and SC122 boost inputs from as low as 0.7V to a regulated output
settable from 1.8V to 5.0V and are available in tiny 1.5x2mm ultra-thin (0.6mm
max.) plastic packages. The devices are aimed at portable applications powered
by alkaline, NiMH, or 1-cell Li-ion batteries, or as point-of-load regulators
in non-portable applications where a low voltage needs to be boosted to a
higher voltage rail for localized use.
The SC120 features 1.2MHz low-noise PWM
operation, an internal low-on-resistance switch and synchronous rectifier for
up to 94% efficiency, automatic PSAVE mode for light-load efficiency, an
anti-ringing circuit that dampens stray oscillations on the inductor terminal,
±1.5% initial accuracy, internal/external feedback modes, soft-start, thermal
and current limit protection, and a 0.1µA real shutdown mode that reverses the
rectifier’s body-diode and actively discharges the output fully to ground.
For highly noise sensitive applications, the SC121 eliminates the PSAVE mode in
favor of forced-PWM operation at all loads. And for specialized keep-alive
applications, the SC122 utilizes PSAVE mode only and allows the output voltage
to float high during shutdown by eliminating active discharge. The SC122 also
limits the input to no more than 1.6V and the output to a fixed 3.3V.
For ease of use, the SC12x devices utilize internal loop compensation and
internal soft-start to minimize external components. Grounding the feedback pin
enables internally fixed 3.3V regulation mode, which requires only three small
external components: two ceramic capacitors and an inductor.
For setting other output voltages from 1.8V to 5.0V via external feedback, only
two small resistors and a small feed-forward capacitor are added.
The SC120, SC121, and SC122 are available in a 1.5x2mm, 6-pin MLPD-UT package.
The SC120 is also available in a 6-pin SOT23 package. All devices are
lead-free, halogen-free, and WEEE and RoHS compliant to meet worldwide
environmental and regulatory requirements.
The SC120, SC121, and SC122 (Order codes: SC120ULTRT, SC121ULTRT,
SC122ULTRT) are priced at $0.80 each in MLPD-UT package in 3,000-piece lots.
The SC120 (Order code: SC120SKTRT) is priced at $0.71 each in SOT23
package in 3,000-piece lots. Each device is available immediately in production