July 2009 Doc ID 6738 Rev 25 1/28
28
LD1085xx
3 A low drop positive voltage regulator adjustable and fixed
Features
■Typical dropout 1.3 V (at 3 A)
■Three terminal adjustable or fixed output
voltage 1.5 V, 1.8 V, 2.5 V, 3.3 V, 5 V, 12 V.
■Automotive grade product: adjustable VOUT
only in TO-220 full pack package
■Guaranteed output current up to 3 A
■Output tolerance ± 1 % at 25°C and ± 2 % in full
temperature range
■Internal power and thermal limit
■Wide operating temperature range -40 °C to
125 °C
■Package available: TO-220, TO-220FP,
DPAK, D2PAK, D2PAK/A
■Pinout compatibility with standard adjustable
VREG
Description
The LD1085xx is a low drop voltage regulator
able to provide up to 3 A of output current.
Dropout is guaranteed at a maximum of 1.2 V at
the maximum output current, decreasing at lower
loads. The LD1085xx is pin to pin compatible with
the older 3-terminal adjustable regulators, but has
better performances in term of drop and output
tolerance.
A 2.85 V output version is suitable for SCSI-2
active termination. Unlike PNP regulators, where
a part of the output current is wasted as quiescent
current, the LD1085xx quiescent current flows
into the load, so increase efficiency. Only a 10 µF
minimum capacitor is need for stability.
The device is supplied in TO-220, TO-220FP,
DPAK, D2PAK and D2PAK/A. On chip trimming
allows the regulator to reach a very tight output
voltage tolerance, within ± 1 % at 25 °C.
The LD1085xx is available as automotive grade in
TO-220FP package only, for the option of
adjustable output voltage whose commercial part
number is shown in the Table 11: Order codes.
This device is 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
D2PAK/A
TO-220
D2PAKDPAK
Table 1. Device summary
Part numbers
LD1085XX LD1085XX25
LD1085XX15 LD1085XX33
LD1085XX18 LD1085XX50
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