uP0114
Functional Description
Definitions
Supply Input Voltage
The uP0114 works with 2.4V ~ 5.5V supply input voltage
at VIN pin. The VIN voltage is continuosly monitored for
power on reset (POR). The IC is disabled until POR is
asserted. The POR level is about 2.2V at VIN rising. The
input voltage requires a minimum 2.2uF ceramic bypassing
physically near the IC.
Some important terminologies for LDO are specified
below.
Dropout Voltage
The input/output voltage differential at which the regulator
output no longer maintains regulation against further
reductions in input voltage. Measured when the output
drops 2% below its nominal value. Dropout voltage is
affected by junction temperature, load current and
minimum input supply requirements.
Output Voltage Regulation
The output voltage is tighly regulated to 1.6 times of VSET
voltage until the uP0114 enters dropout region. When
FON# is pulled lower than 0.4V, the uP0114A fully turns
on the pass transistor and connects VOUT to VIN. This
runs the fan with full speed.
Line Regulation
The change in output voltage for a change in input voltage.
The measurement is made under conditions of low
dissipation or by using pulse techniques such that average
chip temperature is not significantly affected.
Current Limit
The uP0114 features a fold-back current limit function.
When over current is triggered, the output current limit
threshold is proportional to VOUT/VSET and is typically 1A
Load Regulation
The change in output voltage for a change in load current
at constant chip temperature. The measurement is made
under conditions of low dissipation or by using pulse
techniques such that average chip temperature is not
significantly affected.
when VOUT = 1.6 x VSET
.
Maximum Power Dissipation
The maximum total device dissipation for which the
regulator will operate within specifications.
General Description
The uP0114 is high performance positive voltage regulator
specifically designed for applications where very low
dropout voltage is required. It is capable of delivering 0.6A
output current with 150mV dropout voltage and 115uA
quiescent current.
With 250mΩ PMOSFET pass transistor, the uP0114 tightly
regulates the output voltage to 1.6 times of VSET voltage
until it enters dropout regions. The uP0114 provides
excellent regulation over variations in line, load and
temperature. The uP0114A fully turns on the pass
transistor when the FON# is given low.
Other features include fold-back over current protection
and over temperature protection. This part is available in
FSOP-8L and SOT23-8L packages.
uPI Semiconductor Corp., http://www.upi-semi.com
Rev. P00, File Name: uP0114-DS-P0000
3
UNITPOWER [ ShenZhen XinDeYi Electronics Co., Ltd. ]
