features
Dual-Input, Single-Output MOSFET Switch
With No Reverse Current Flow (No Parasitic
Diodes)
IN1 . . . 250-mW, 500-mA N-Channel;
18-mA Supply Current
IN2 . . . 1.3-W, 100-mA P-Channel;
0.75-mA Supply Current (VAUX Mode)
Advanced Switch Control Logic
CMOS and TTL Compatible Enable Input
Controlled Rise, Fall, and Transition Times
2.7 V to 5.5 V Operating Range
SOT-23-5 and SOIC-8 Package
–40°C to 85°C Ambient Temperature Range
2-kV Human Body Model, 750-V Charged
Device Model, 200-V Machine-Model
ESD Protection

typical applications
Notebook and Desktop PCs
Cell phone, Palmtops, and PDAs
Battery Management

description
The TPS2104 and TPS2105 are dual-input, single-output power switches designed to provide uninterrupted
output voltage when transitioning between two independent power supplies. Both devices combine one
n-channel (250 mW) and one p-channel (1.3 W) MOSFET with a single output. The p-channel MOSFET (IN2)
is used with auxiliary power supplies that deliver lower current for standby modes. The n-channel MOSFET
(IN1) is used with a main power supply that delivers higher current required for normal operation. Low
on-resistance makes the n-channel the ideal path for higher main supply current when power-supply regulation
and system voltage drops are critical. When using the p-channel MOSFET, quiescent current is reduced to
0.75 mA to decrease the demand on the standby power supply. The MOSFETs in the TPS2104 and TPS2105
do not have the parasitic diodes, typically found in discrete MOSFETs, thereby preventing back-flow current
when the switch is off.