July 2008 Rev 9 1/20
20
KD1084xx
KD1084Axx
5 A low drop positive voltage regulator adjustable and fixed
Features
■ Typical dropout 1.3 V (at 5 A)
■ Three terminal adjustable or fixed output
voltage 1.8 V, 3.3 V.
■ Guaranteed output current up to 5 A
■ Output tolerance ±1 % at 25 °C and ± 2 % in full
temperature range for the "A" version
■ Output tolerance ± 2 % at 25 °C and ± 3 % in
full temperature range internal power and
thermal limit
■ Wide operating temp. range -40 °C to 125 °C
■ Package available: D
2
PAK and DPAK
■ Pinout compatibility with standard adjustable
VREG
Description
The KD1084xx is a low drop voltage regulator
able to provide up to 5 A of output current.
Dropout is guaranteed at a maximum of 1.5 V at
the maximum output current, decreasing at lower
loads. The KD1084xx is pin to pin compatible with
he 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 KD1084xx quiescent current flows
into the load, so increase efficiency. Only a 10 µF
minimum capacitor is need for stability.
The devices are supplied in D
2
PAK and DPAK. On
chip trimming allows the regulator to reach a very
tight output voltage tolerance, within ±1% at 25 °C
for "A" version and ± 2 % at 25 °C for standard
version.
DPAK
D
2
PAK
Table 1. Device summary
Part numbers
Order codes
D
2
PAK DPAK Output voltage Tolerance
KD1084AXX18 KD1084AD2T18R 1.8 V 1%
KD1084XX33 KD1084DT33R 3.3 V 2%
KD1084AXX33 KD1084ADT33R 3.3 V 1%
KD1084XX KD1084DT-R ADJ 2%
KD1084AXX KD1084ADT-R ADJ 1%
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