February 2012 Doc ID 2574 Rev 25 1/50
50
LFxxAB
LFxxC
Very low drop voltage regulators with inhibit
Features
■Very low dropout voltage (0.45 V)
■Very low quiescent current (typ. 50 µA in OFF
mode, 500 µA in ON mode)
■Output current up to 500 mA
■Logic-controlled electronic shutdown
■Output voltages of 1.5; 1.8; 2.5; 3.3; 4.7; 5; 6;
8; 8.5; 9; 12 V
■Automotive Grade product: 1.8 V, 2.5 V, 3.3 V,
5.0 V, 8.0 V, 8.5 V VOUT in DPAK and PPAK
packages
■Internal current and thermal limit
■Only 2.2 µF for stability
■Available in ± 1 % (AB) or ± 2 % (C) selection
at 25 °C
■Supply voltage rejection: 80 db (typ.)
■Temperature range: -40 to 125 °C
Description
The LFxxAB/LFxxC are very low drop regulators
available in PENTAWATT, TO-220, TO-220FP,
DPAK and PPAK package and in a wide range of
output voltages. The very low drop voltage (0.45
V) and the very low quiescent current make them
particularly suitable for low noise, low power
applications and specially in battery powered
systems. In the 5 pins configuration (PENTAWATT
and PPAK) a shutdown logic control function is
available (pin 2, TTL compatible). This means that
when the device is used as a local regulator, it is
possible to put a part of the board in standby,
decreasing the total power consumption. In the
three terminal configuration the device has the
same electrical performance, but is fixed in the
ON state. It requires only a 2.2 µF capacitor for
stability allowing space and cost saving. The LFxx
is available as Automotive Grade in DPAK and
PPAK packages, for the options of output voltages
whose commercial part numbers are shown in the
order codes. These devices are qualified
according to the specification AEC-Q100 of the
Automotive market, in the temperature range - 40
°C to 125 °C, and the statistical tests PAT, SYL,
SBL are performed.
TO-220FP
PENTAWATT
TO-220
DPAKPPAK
Table 1. Device summary
Part numbers
LF15AB LF25C LF33AB LF60C LF80AB LF90C LF120AB
LF18C LF25AB LF50C LF60AB LF85C LF90AB
LF18AB LF33C LF50AB LF80C LF85AB LF120C
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