AAT3258
300mA LDO Linear Regulator with µP Reset
General Description
The AAT3258 combines a high performance, low
noise, 300mA low dropout (LDO) linear regulator
with a microprocessor reset monitor. The 300mA
output capability of the LDO regulator makes this
device ideal for use with microprocessors and DSP
cores in portable products. The microprocessor
reset monitor section has very low quiescent cur-
rent consumption and has an active low reset out-
put. The AAT3258 has separate input pins for the
reset monitor and LDO regulator so they may be
operated from independent sources for increased
design flexibility. This device features very low qui-
escent current, typically less than 71µA.
The LDO regulator has low dropout voltage, typical-
ly 400mV at the full output current level, making it
ideal for portable applications where extended bat-
tery life is critical. The AAT3258 LDO regulator sec-
tion has complete over-current/short-circuit and
over-temperature protection circuits to guard against
extreme operating conditions. The device also has
an active output pull down function when disabled.
The AAT3258 is available in a Pb-free, space-sav-
ing 8-pin TSOPJW package. This device is capa-
ble of operation over a -40°C to +85°C temperature
range.
Features
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
PowerLinear
™
Integrated LDO Regulator with µP Reset
300mA Output LDO Regulator
Low Dropout Regulator, 400mV at 300mA
High LDO Output Voltage Accuracy, Typically
1.5%
Very Low Noise and High Power Supply
Rejection Ratio (PSRR) LDO
Low Quiescent Current at 71µA
LDO Over-Current/Short-Circuit Protection
LDO Over-Temperature Protection
LDO Power Saving Shutdown Mode
Independent Device Power Inputs
High Accuracy Reset Monitor Threshold: ±1.5%
Active Low Push-Pull Monitor Reset Output
<2.0µA of Shutdown Current
Uses Low Equivalent Series Resistance
(ESR) Ceramic Capacitors
-40°C to +85°C Temperature Range
8-Pin TSOPJW Package
Applications
•
•
•
•
•
•
•
Cellular Phones
Digital Cameras
Handheld Instrumentation
Microprocessor/DSP Core/IO Power
Notebook Computers
PDAs and Handheld Computers
Portable Communication Devices
Typical Application
100k
VIN
VDET
RESET
RESET OUT
VIN
µP Reset
Manual Reset
VOUT
LDO VOUT
AAT3258
MR
GND
1µF
LDO Shutdown
SHDN
BYP
10nF
2.2µF
3258.2006.03.1.6
1
AAT3258
300mA LDO Linear Regulator with µP Reset
Pin Descriptions
Pin #
1
2
Symbol
VIN
SHDN
Function
LDO voltage regulator input pin. This pin should be decoupled with 1µF or
greater capacitor. See application information.
LDO voltage regulator shutdown pin. This pin should not be left floating.
When connected low, all the internal circuitry is powered down. When high, it
is in normal operation.
Microprocessor reset input power supply pin. It may be connected to V
IN
.
Manual reset active low input. A logic low signal on MR asserts a reset condi-
tion. Asserted reset continues as long as MR is low and for a minimum of
150ms after MR returns high.
Reset output remains low while V
DET
is below the reset threshold and remains
so for a minimum of 150ms after V
DET
rises above the reset threshold.
Ground connection pin.
LDO voltage regulator bypass capacitor connection. To improve AC ripple
rejection and decrease LDO regulator self noise, connect a 10nF ceramic
capacitor between this pin and GND.
LDO voltage regulator output pin; should be decoupled with a 2.2µF or
greater value low ESR ceramic capacitor.
3
4
VDET
MR
5
6
7
RESET
GND
BYP
8
OUT
Pin Configuration
TSOPJW-8
(Top View)
VIN
SHDN
VDET
MR
1
8
OUT
BYP
GND
RESET
2
7
3
6
4
5
2
3258.2006.03.1.6
AAT3258
300mA LDO Linear Regulator with µP Reset
Absolute Maximum Ratings
1
T
A
= 25°C, unless otherwise noted.
Symbol
V
IN
V
RESET
V
SHDNIN(MAX)
I
OUT
I
RESET
∆V
DET
/∆t
T
J
Description
Input Voltage
RESET to GND
Maximum SHDN to Input Voltage
LDO Regulator DC Output Current
Maximum Reset Output Current
Maximum Rate of V
DET
Rise
Operating Junction Temperature Range
Value
6.0
-0.3 to V
DET
+ 0.3
0.3
P
D
/(V
IN
- V
O
)
20
100
-40 to 150
Units
V
V
V
mA
mA
V/µs
°C
Thermal Information
2
Symbol
θ
JA
P
D
Description
Maximum Thermal Resistance
Maximum Power Dissipation
Value
150
833
Units
°C/W
mW
Recommended Operating Conditions
Symbol
V
IN
V
DET
T
Description
Input Voltage to LDO
3
Input Voltage to µP Reset (0° to 70°C)
Ambient Temperature Range
Value
(V
OUT
+ V
DO
) to 5.5
1.0 to 5.5
-40 to +85
Units
V
V
°C
1. Stresses above those listed in Absolute Maximum Ratings may cause permanent damage to the device. Functional operation at condi-
tions other than the operating conditions specified is not implied. Only one Absolute Maximum Rating should be applied at any one time.
2. Mounted on a demo board.
3. To calculate minimum input voltage, use the following equation: V
IN(MIN)
= V
OUT(MAX)
+ V
DO(MAX)
as long as V
IN
≥
2.5V.
3258.2006.03.1.6
3
AAT3258
300mA LDO Linear Regulator with µP Reset
Electrical Characteristics
1
T
J
= 25°C, unless otherwise noted.
Symbol
Description
Conditions
I
OUT
= 1mA T
A
= 25°C
to 300mA
T
A
= -40°C to 85°C
V
OUT
> 1.2V
V
OUT
< 0.4V
V
IN
= 5V, No Load, SHDN = V
IN
V
IN
= 5V, SHDN = 0V
V
IN
= V
OUT
+ 1 to 5.0V
I
OUT
= 300mA, T
R
/T
R
= 2µs,
V
IN
= V
OUT
+ 1V to V
OUT
+ 2V
I
OUT
= 1mA to 300mA, T
R
< 5µs
BYP = Open
I
OUT
= 300mA
Min
-1.5
-2.5
300
Typ
Max
1.5
2.5
Units
300mA LDO Regulator
V
OUT
I
OUT
I
SC
I
GND
I
SHDN
∆V
OUT
/V
OUT
*∆V
IN
∆V
OUT
(line)
V
OUT
(load)
T
ENDLY
V
DO
V
IL
V
IH
I
IL
I
IH
PSRR
Output Voltage
Output Current
Short-Circuit Current
Ground Current
Shutdown Current
Line Regulation
Dynamic Line Regulation
Dynamic Load Regulation
Enable Delay Time
Dropout Voltage
2
Input Low Voltage
Input High Voltage
Input Low Current
Input High Current
Power Supply Rejection Ratio
Over-Temperature Shutdown
Threshold
Over-Temperature Shutdown
Hysteresis
Output Noise
Output Voltage Temperature
Coefficient
%
mA
mA
µA
µA
%/V
mV
mV
µs
mV
V
V
µA
µA
dB
600
70
125
1.0
0.09
2.5
60
15
400
1.5
1.0
1.0
600
0.6
1kHz
I
OUT
= 10mA,
10kHz
C
BYP
= 10nF
1MHz
67
47
45
145
12
50
22
T
SD
T
HYS
e
N
TC
°C
°C
µV
RMS
ppm/°C
1. The AAT3258 is guaranteed to meet performance specifications over the -40°C to 85°C operating temperature range and is assured
by design, characterization, and correlation with statistical process controls.
2. V
DO
is defined as V
IN
- V
OUT
when V
OUT
is 98% of nominal.
4
3258.2006.03.1.6
AAT3258
300mA LDO Linear Regulator with µP Reset
Electrical Characteristics
1
T
A
= 25°C, unless otherwise noted.
Symbol
Description
Conditions
T
A
= 0°C to +70°C
T
A
= -40°C to +85°C
V
CC
= 5.5V
V
CC
= 3.0V
V
DET
= 3.0V
V
DET
> V
TH
AAT3258xxx-x.x-R
T
A
= 25°C
AAT3258xxx-x.x-Y
V
DET
= V
TH
to (V
TH
- 100mV)
150
10
30
Min
1
1.2
Typ
Max
5.5
5.5
3.0
2.0
2.0
1.0
2.67
2.49
Units
Microprocessor Reset Monitor
V
DET
I
Q
I
DD
I
DOFF
V
TH
∆V
TH
/°C
T
P
T
RDY
T
MR
MRGI
R
MR
T
MD
V
IH
V
IL
V
OL
Input Voltage Range
Quiescent Current
Operating Supply Current
Reset Leakage Current
Reset Threshold Voltage
RESET Threshold Tempco
Reset Propagation Delay
Reset Active Timeout Period
MR Minimum Pulse Width
MR Glitch Immunity
MR Pull-Up Resistance
MR to Reset Propagation
Delay
MR Input Threshold (high)
MR Input Threshold (low)
V
µA
µA
µA
V
ppm/°C
µs
ms
µs
ns
kΩ
µs
0.25
×
V
DET
0.3
V
0.4
V
V
1.05
0.85
0.85
2.59
2.41
2.63
2.45
40
15
250
100
65
0.5
400
90
Reset Low Voltage
V
OH
Reset High Voltage
V
DET
= V
TH(MAX)
0.7
×
V
DET
V
DET
= V
TH(MAX)
I
SINK
= 1.2mA, V
DET
= V
TH(MIN)
,
V
TH
≤
3.08V, Reset Asserted
I
SINK
= 3.2mA, V
DET
= V
TH(MIN)
,
V
TH
>
3.08V, Reset Asserted
I
SOURCE
= 800µA, V
DET
> 3.08V,
V
DET
- 1.5
V
DET
> V
TH(MAX)
I
SOURCE
= 500µA, V
DET
>
0.8 * V
DET
V
TH(MAX)
, V
TH
≤
3.08V
V
1. The AAT3258 is guaranteed to meet performance specifications over the -40°C to 85°C operating temperature range and is assured
by design, characterization, and correlation with statistical process controls.
3258.2006.03.1.6
5
京公网安备 11010802033920号
EEWORLD
