LD49300
3 A very low-dropout voltage regulator
Datasheet
-
production data
Applications
•
Graphics processors
•
PC add-in cards
•
Microprocessor core voltage supply
PPAK
•
Low voltage digital ICs
•
High efficiency linear power supplies
•
SMPS post regulators
Features
•
Input voltage range:
– V
I
= 1.4 V to 5.5 V
– V
BIAS
= 3 V to 6 V
•
Stable with ceramic capacitors
•
±1.5% initial tolerance
•
Maximum dropout voltage (V
I
- V
O
) 400 mV
over the operating temperature range
•
Adjustable output voltage starting from 0.8 V
•
Very fast transient response (up to 10 MHz
bandwidth)
•
Excellent line and load regulation
specifications
•
Logic-controlled shutdown option
•
Thermal shutdown and current limit protection
Description
The LD49300 is a high-bandwidth, low-dropout,
3.0 A voltage regulator, ideal for powering core
voltages of low power microprocessors. The
LD49300 implements a dual supply configuration,
which guarantees a very low output impedance
and a fast transient response. The LD49300
requires a bias input supply and a main input
supply, allowing ultra-low input voltages on the
main supply rail. The input supply operates from
1.4 V to 5.5 V and bias supply requires between 3
V and 6 V to work properly. The LD49300 offers
fixed output voltages from 0.8 V to 1.8 V and
adjustable output voltages from 0.8 V. The
LD49300 requires a minimum output capacitance
for stability, and works optimally with small
ceramic capacitors.
•
Junction temperature range: - 25 °C to 125 °C
Table 1. Device summary
Order codes
LD49300PT08R
(1)
LD49300PT10R
LD49300PT12R
1. Adjustable version.
Package
PPAK (tape and reel)
PPAK (tape and reel)
PPAK (tape and reel)
Packaging
2500 pieces per reel
2500 pieces per reel
2500 pieces per reel
May 2014
This is information on a product in full production.
DocID12861 Rev 4
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Contents
LD49300
Contents
1
2
3
4
5
6
7
8
Typical application circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Alternative application circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Typical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Application hints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
8.1
8.2
8.3
8.4
8.5
8.6
8.7
8.8
8.9
8.10
Input supply voltage (VIN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Bias supply voltage (VBIAS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
External capacitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Output capacitor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Minimum load current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Power sequencing recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Power dissipation/heatsinking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
PPAK package heatsinking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Adjustable regulator design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Enable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
9
10
11
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Packaging mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
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LD49300
Typical application circuits
1
Typical application circuits
Figure 1. Adjustable version
Figure 2. Fixed version with enable
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Alternative application circuits
LD49300
2
Alternative application circuits
Figure 3. Single supply voltage solution
Figure 4. LD49300 and DC-DC pre-regulator to reduce power dissipation
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LD49300
Pin configuration
3
Pin configuration
Figure 5. Pin connection (top view)
Table 2. Pin description
Pin
1
ADJ
2
3
4
5
V
IN
GND
V
OUT
V
BIAS
Adjustable regulator feedback input connected to resistor voltage divider
Input voltage regulator
Ground (tab is connected to ground)
Regulator output
Input bias voltage powers the circuitry on the regulator except the output power device
Symbol
EN
Note
Enable (input): logic high = enable, logic low = shutdown
DocID12861 Rev 4
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