AQ1117
Low Dropout
1 Amp Voltage Regulator
Product Specification
Revision 1.5
September 19, 2005
General Description
The AQ1117 is a low dropout three terminal
voltage regulator, offered in popular fixed options
or an adjustable version that can set a precise
voltage from 1.22V to 12V with two external
resistors.
AQ1117 is offered in SOT-89 which has a lower
thermal resistance and fits in smaller foot print
than a standard SOT-223.
With a dropout
voltage of less than one volt, the AQ1117 can be
used in applications where drop out voltage and
size are an issue.
To assure accuracy within 1.5% over
temperature the heart of the AQ1117 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
•
PC motherboards
•
Switching power supply post-regulation
•
Telecom equipment
•
DVD video player
Features
•
Featured in small
SOT- 89
package
•
Vout tolerance 1.5% over temperature
•
Stable with low cost 1uF capacitor
•
Low dropout voltage (1V at 1 Amp)
•
Thermal protection with hysteresis
•
Short circuit protection
•
Offered with 1.8V, 2.5V, and 3.3V fixed or
•
adjustable output
RoHS complaint
available
Typical Application
www.acutechnology.com
AQ1117
Acutechnology Semiconductor Inc.
AQ1117
Pin Configuration
SOT-89
Pin Descriptions
Pin Name
V
IN
V
OUT
Ground/Adjust
Function
Accepts + VCC
Regulated Output
- VCC for fixed option / Adjust pin for adjustable option
Functional Block Diagram
www.acutechnology.com
2
Rev. 1.5 September 20, 2005
Acutechnology Semiconductor Inc.
AQ1117
Ordering Information
Device
AQ1117
AQ1117
AQ1117
AQ1117
AQ1117
AQ1117
AQ1117
AQ1117
Note:
The
Operating Tj
0C˚
≤
125C˚
0C˚
≤
125C˚
0C˚
≤
125C˚
0C˚
≤
125C˚
0C˚
≤
125C˚
0C˚
≤
125C˚
0C˚
≤
125C˚
0C˚
≤
125C˚
%Tol
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
PKG Type
SOT-89-3
SOT-89-3
SOT-89-3
SOT-89-3
SOT-89-3
SOT-89-3
SOT-89-3
SOT-89-3
V
OUT
1.8V
1.8V
2.5V
2.5V
3.3V
3.3V
ADJ
ADJ
Wrap
T&R
T&R
T&R
T&R
T&R
T&R
T&R
T&R
Ordering Number
AQ1117CY-M1-18-TR
AQ1117CY-M1-18-TRL
AQ1117CY-M1-25-TR
AQ1117CY-M1-25-TRL
AQ1117CY-M1-33-TR
AQ1117CY-M1-33-TRL
AQ1117CY-M1-AJ-TR
AQ1117CY-M1-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
Power Dissipation (Internally limited)
Maximum Junction Temperature
Operating Junction Temperature Range
Storage Temperature Range
Lead Temperature (Soldering, 4sec.) SOT packages
150
0 to 125
-65 to 150
300
°C
°C
°C
°C
Value
18
Units
Volts
Thermal Management
Thermal Resistance (Junction to Tab)
SOT-89
Typical Value
10
Units
°C/W
Thermal Resistance (Junction to Ambient)
SOT-89 (tab soldered to 1 in
2
1 oz. copper PCB)
Typical Value
30
Units
°C/W
www.acutechnology.com
3
Rev. 1.5 September 20, 2005
Acutechnology Semiconductor Inc.
AQ1117
Electrical Specifications
Electrical characteristics are guaranteed over the full temperature range 0ºC <Tj< 125ºC. Ambient temperature
must be de-rated based upon power dissipation and package thermal characteristics. Unless otherwise
specified: V
IN
= (V
OUT
+ 1.5V), I
OUT
= 10 mA, Tj = 25C. All 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
0°C
≤Tj ≤
125°C
∆V
IN
= V
OUT
+ (1.5V to 10V)
∆I
OUT
= (10mA to 1 Amp)
I
OUT
= 100 mA
VD
Drop out Voltage
(1, 2)
I
OUT
= 500 mA
I
OUT
= 1 Amp
ISC
IQON
Current Limit
(1)
Quiescent Current ON
V
IN
-V
OUT
= 2V
V
IN
= 5V
0°C
≤Tj ≤
125°C
Adjustable version only
0°C
≤Tj ≤
125°C
Adjustable version only
10mA
≤
I
OUT
≤
1Amp
1.4
≤
V
IN
≤
18V
To Maintain regulation
1.208
1.202
20
0.2
0.5
0.005
0.5
0.003
Vin = 5V
Junction Temperature
60
72
150
25
1.220
1.1
-1.5
Typ
V
OUT
V
OUT
0.035
0.2
0.91
0.93
0.95
1.5
7.5
9.0
10
1.232
1.238
40
5.0
2.0
Max
+1
+1.5
0.2
0.4
0.95
0.95
1.0
Units
%
%
%
%
V
V
V
A
mA
mA
V
V
µA
µA
mA
%/°C
%/°C
%
V
OUT
dB
°C
°C
VADJ
IADJ
∆
IADJ
I
QMIN
TC
TS
V
N
PSRR
TSD
TSD
HYST
Reference Voltage
Adjust Pin Current (5)
Adjust Pin Current (5)
Change
Minimum Load Current (5)
Temperature Coefficient
Temperature Stability
RMS Output Noise
(3)
Ripple Rejection Ratio
(4)
Thermal Shutdown
TSD Hysteresis
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. 1.5 September 20, 2005
Acutechnology Semiconductor Inc.
AQ1117
Application Notes
1. Typical Application
Notes:
1. Output voltage is 1.22V * (R2 +R1)/R1
2. Input and output capacitors should be located close to the device.
3. The AQ1117 will remain stable with C1 and C2 as low as 1.0µF. Overall transient
performance is improved with increased capacitance.
2. Stability
An input capacitor is recommended. A 1.0µF capacitor on the input is a suitable input
bypassing for almost all applications. A larger capacitor is also suitable. In the adjustable
version the “adjust” terminal can be bypassed to ground with a bypass capacitor (C
ADJ
) to
improve ripple rejection. This bypass capacitor prevents ripple from being amplified as the
output voltage is increased. At any ripple frequency, the impedance of the C
ADJ
should be
less than R1 (being R1 the resistor between the output and the adjust pin) to prevent the
ripple from being amplified:
Z = 1/(2π*f
RIPPLE
* C
ADJ
) < R1
R1 is normally in the range of 1KΩ.
The output capacitor is critical in maintaining regular stability. The AQ1117 is stable with an
output capacitor greater than. Of course any increase of the output capacitor will merely improve
the loop stability and the load transient response. In the case of the adjustable regulator, when
the C
ADJ
is used, a larger output capacitance may be required. Tantalum Capacitors exhibit the
best stability over a wide range of loads and are recommended.
3. Output Voltage
The AQ1117 adjustable version develops a 1.22V reference voltage between the output and
the adjust pin terminal. This voltage is applied across the resistor R1 to generate a constant
current (I1). The current from the adjust terminal could introduce error to the output, but since
it is very small (< 20µA) compared with the current I1 and very constant with line and load
changes, the error can be ignored. The constant current I1 then flows through resistor R2
and sets the output voltage to the desired level.
www.acutechnology.com
5
Rev. 1.5 September 20, 2005
嵌入式系统
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
