This is information on a product in full production.
January 2014 DocID9587 Rev 15 1/22
LD3985
Ultra low drop and low noise BiCMOS voltage regulators
Datasheet
-
production data
Features
• Input voltage from 2.5 V to 6 V
• Stable with low ESR ceramic capacitors
• Ultra low-dropout voltage (60 mV typ. at 150
mA load, 0.4 mV typ. at 1 mA load)
• Very low quiescent current (85 µA typ. at no
load, 170 µA typ. at 150 mA load; max.1.5 µA
in OFF mode)
• Guaranteed output current up to 150 mA
• Wide range of output voltage: 1.22 V; 1.8 V; 2.5
V; 2.6 V; 2.7 V; 2.8 V; 2.9 V; 3 V; 3.3 V; 4.7 V
• Fast turn-on time: typ. 200 µs [C
O
= 1 µF, C
BYP
= 10 nF and I
O
= 1 mA]
• Logic-controlled electronic shutdown
• Internal current and thermal limit
• Output low noise voltage 30 µV
RMS
over 10 Hz
to 100 kHz
• SVR of 60 dB at 1 kHz, 50 dB at 10 kHz
• Temperature range: - 40 °C to 125 °C
Description
The LD3985 provides up to 150 mA, from 2.5 V to
6 V input voltage. The ultra low drop voltage, low
quiescent current and low noise make it suitable
for low power applications and in battery-powered
systems. Regulator ground current increases
slightly in dropout only, prolonging the battery life.
Power supply rejection is better than 60 dB at low
frequencies and rolls off at 10 kHz. High power
supply rejection is maintained down to low input
voltage levels common to battery operated
circuits. Shutdown logic control function is
available, this means that when the device is
used as local regulator, it is possible to put a part
of the board in standby, decreasing the total
power consumption. The LD3985 is designed to
work with low ESR ceramic capacitors. Typical
applications are in mobile phones and similar
battery-powered wireless systems.
Flip-chip
SOT23-5L
TSOT23-5L
(1.57 x 1.22)
Table 1. Device summary
Part numbers
LD3985XX122 LD3985XX28
LD3985XX18 LD3985XX29
LD3985XX25 LD3985XX30
LD3985XX26 LD3985XX33
LD3985XX27 LD3985XX47
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