AQ8211
Ultra-Low Dropout
500mA Voltage Regulator
with Enable
Product Specification
Revision 2.1
January 22, 2007
General Description
The AQ8211 is an ultra-low dropout voltage
regulator capable of delivering
500 mA
to the
load. It is adjustable and can set a precise
voltage from 1.22V to 12V with two external
resistors. The AQ8211 meets all specifications
down to 1.22V output, unlike CMOS LDO’s which
loose performance with outputs below 2.25V.
The
enable
pin provides a remote turn-off for low
power consumption. It draws virtually zero current
in shutdown mode and implements Sequential,
Ratiometric,
or
Simultaneous
sequencing
schemes. This also allows for a separate bias
connection from the pass transistor in order to
achieve
ultra low dropout
from V
IN
to V
OUT
.
Reverse current protection
blocks current
flowing from V
OUT
to V
IN
when the AQ8211 is
disabled. No current flows.
To assure accuracy over temperature, the heart
of the AQ8211 is a self-correcting AcuRef™
bandgap reference.
On-chip current limit and thermal shutdown with
hysteresis protects against any combination of
overload and ambient temperature that might
cause the junction temperature to exceed safe
limits.
Applications
•
Graphic cards and PC motherboards
•
Cell Phones
•
DVD video player
Replacement for:
•
LX8211
Features
•
Extended Temp Range
-40C˚
≤
125C˚
•
Low dropout voltage (350mV at
500 mA)
•
Enable pin implements sequencing
•
Reverse current protection
•
Featured in the very small SOT-23
•
•
•
•
•
package
Stable with low cost 1
µ
F capacitor
Low ground current <100
µA
Thermal protection with hysteresis
Short circuit protection
RoHS compliant
Typical Application
www.acutechnology.com
AQ8211
Acutechnology Semiconductor Inc.
AQ8211
Pin Configuration
Pin Descriptions
Pin Name
V
IN
Ground
E
NABLE
Adjust
V
OUT
Function
+ Unregulated Input Voltage, Collector of Pass Transistor
- Ground
Active high, E
NABLE
> (0.95V + V
OUT
), Chip bias circuit supply
OFF low, E
NABLE
< 0.25V
Adjust input. Connect to resistive feed back divider.
Regulated Output
Functional Block Diagram
www.acutechnology.com
2
Rev. 2.1
January 22, 2006
Acutechnology Semiconductor Inc.
AQ8211
Ordering Information
Device
AQ8211
AQ8211
AQ8211
AQ8211
Note:
The
Operating Tj
-40C˚
≤
125C˚
-40C˚
≤
125C˚
-40C˚
≤
125C˚
-40C˚
≤
125C˚
%Tol
1.0
1.0
1.0
1.0
PKG Type
SOT-23-5
SOT-23-5
SOT-23-5
SOT-23-5
V
OUT
1.8V
2.5V
3.3V
ADJ
Wrap
T&R
T&R
T&R
T&R
Ordering Number
AQ8211AY-M5-18-TRL
AQ8211AY-M5-25-TRL
AQ8211AY-M5-33-TRL
AQ8211AY-M5-AJ-TRL
TRL parts are Lead Free and RoHS compliant.
Absolute Maximum Ratings
Stress greater than those listed under “Absolute Maximum Ratings” may cause permanent damage to the
device. These stress ratings only, and functional operation of the device at these or any conditions beyond
those indicated under recommended Operating Conditions is not implied. Exposure to “Absolute Maximum
Rating” for extended periods may affect device reliability. Use of standard ESD handling precautions is
required.
Parameter
Maximum V
IN
Maximum V
ENABLE
Power Dissipation (Internally limited)
Maximum Junction Temperature
Operating Junction Temperature Range
Storage Temperature Range
Lead Temperature (Soldering, 4 sec.) SOT- 23-5 package
150
-40C˚
≤
125C˚
-65 to 150
300
°C
°C
°C
°C
Value
18
18
Units
Volts
Volts
Thermal Management
Thermal Resistance (Junction to Ambient)
SOT-23-5 (minimum foot print)
Typical
Value
220
Typical
Value
170
Units
°C/W
Units
°C/W
Thermal Resistance (Junction to Ambient)
SOT-23-5 (Soldered to 1 in
2
1 oz. copper PCB)
www.acutechnology.com
3
Rev. 2.1
January 22, 2006
Acutechnology Semiconductor Inc.
AQ8211
Electrical Specifications
Electrical characteristics are guaranteed over the full temperature range -40ºC <Tj< 125ºC. Ambient
temperature must be de-rated based upon power dissipation and package thermal characteristics. Unless
otherwise specified: V
ENABLE
= V
IN
= (V
OUT
+ 1.5V), I
OUT
= 10 mA, Tj = 25C. Values in
bold
are over the full
temperature range.
Symbol
VOUT
LNREG
LDREG
Parameter
Output Voltage
(1)
Line Regulation
(1)
Load Regulation
(1)
Conditions
Min
-1
-40°C
≤Tj ≤
125°C
∆V
EN
= V
OUT
+ (1.5V to 10V)
∆I
OUT
= (10mA to 250 mA)
I
OUT
= 100 mA
VD
Dropout Voltage
(1, 2)
I
OUT
= 250 mA
I
OUT
= 500 mA
ISC
I
GND
I
GND
VIL
VIH
Current Limit
(1)
Ground Current ON
Ground Current ON (5)
Enable Pin Voltage (OFF)
Enable Pin Voltage (ON)
Adjustable version
With respect to GND
With respect to V
OUT
I
OUT
= 10 mA
I
EN
ON
Enable Current ON
I
OUT
= 250 mA
I
OUT
= 500 mA
V
ADJ
I
QMIN
TC
TS
V
N
PSRR
TSD
TSD
HYST
Reference Voltage
Minimum Load Current (5)
Temperature Coefficient
Temperature Stability
RMS Output Noise
(3)
Ripple Rejection Ratio
(4)
Thermal Shutdown
TSD Hysteresis
Vin = 5V
Junction Temperature
60
Adjustable version only
-40°C
≤Tj ≤
125°C
To maintain regulation
1.208
1.202
0.5
0.005
0.5
0.003
72
150
25
0.25
V
EN
-V
OUT
= 2V
600
-1.5
Typ
V
OUT
V
OUT
0.035
0.2
50
150
300
800
100
65
0.45
0.92
0.3
1.8
3.8
1.220
0.95
0.5
3.0
5.0
1.232
1.238
2.0
150
100
Max
+1
+1.5
0.2
0.4
80
200
350
Units
%
%
%
%
mV
mV
mV
mA
µA
µA
V
V
mA
mA
mA
V
V
mA
%/°C
%/°C
%
V
OUT
dB
°C
°C
Notes:
(1) Low duty cycle pulse testing with Kelvin connections required.
(2) Measure (V
IN
- V
OUT
) when
∆V
OUT
,
OR
∆V
REF
= 1%
(3) Bandwidth of 10Hz to 10kHz
(4) 120Hz input ripple
(5) Adjustable version only
www.acutechnology.com
4
Rev. 2.1
January 22, 2006
Acutechnology Semiconductor Inc.
AQ8211
Application Notes
www.acutechnology.com
5
Rev. 2.1
January 22, 2006