Low input voltage, 3-V output voltage, synchronous boost converter with integrated load switch

The TPS61098x is an ultra-low power solution for

products powered by either a one-cell or two-cell

alkaline, NiCd or NiMH, one-cell coin cell or

one-cell Li-Ion or Li-polymer battery. It

integrates either a Low-dropout Linear Regulator

(LDO) or a load switch with a boost converter and

provides two output rails. The boost output

V(MAIN) is designed as an always-on

supply for a main system, and the LDO or load

switch output V(SUB) is to power

peripheral devices.

The TPS61098x has two modes controlled by the MODE

pin: Active mode and Low Power mode. In Active mode, both outputs are enabled with enhanced

response performance. In Low Power mode, the LDO or load switch is disabled to disconnect

peripherals. The TPS61098x consumes only 300-nA quiescent current and can achieve up to 88%

efficiency at 10-µA load in Low Power mode.

The TPS61098x supports automatic pass-through

function. When input voltage is higher than a

pass-through threshold, the boost converter stops

switching and passes the input voltage to the

VMAIN rail; when input voltage is lower than the

threshold, the boost works in Boost mode and

regulates the output at the target value. The

TPS61098x provides different versions for

different output set values.

The TPS61098x can provide up to 50-mA total output

current at 0.7-V input to 3.3-V output conversion.

The boost is based on a hysteretic controller

topology using a synchronous rectifier to obtain

maximum efficiency at minimal quiescent

current.

The TPS61098x is available in 1.5-mm × 1.5-mm WSON

package to enable small circuit layout size.