®
RT9041F
500mA, Low Voltage, LDO Regulator with External Bias Supply
General Description
The RT9041F is a low voltage, low dropout linear regulator
with an external bias supply input. The bias supply drives
the gate of the internal N-MOSFET pass transistor, making
these devices ideal for applications that require low voltage
outputs from low voltage inputs. The RT9041F provides
fixed output voltage from 1V to 2V with 0.1V increments.
Adjustable output voltage is available for the RT9041F by
using external resistors. Other features include current
limit and thermal shutdown to protect regulator from fault
conditions.
The RT9041F is available in a WDFN-8L 2x2 package.
Features
±
2% Output Voltage Accuracy
No Minimum Load Current Required
1V to 5.5V Input Supply Voltage
3V to 5.5V Input Bias Supply Voltage
PGOOD Open-Drain Output
Supports Fixed/Adjustable Output Voltage
Low Supply Current
5μA (max) Shutdown Supply Current
μ
RoHS Compliant and Halogen Free
Applications
Set Top Box
Notebook Computers
VID Power Supplies
PDAs
Cell Phones
Low Dropout Regulators with External Bias Supply
Ordering Information
RT9041F-
Package Type
QW : WDFN-8L 2x2
Lead Plating System
G : Green (Halogen Free and Pb Free)
Output Voltage
10 : 1.0V/Adj
11 : 1.1V/Adj
:
19 : 1.9V/Adj
20 : 2.0V/Adj
Note :
Pin Configurations
(TOP VIEW)
VOUT
ADJ
PGOOD
GND
GND
1
2
3
4
8
7
6
5
9
VIN
NC
VDD
EN
Any fixed output voltage version can be used as Adj output
voltage version.
Richtek products are :
½
WDFN-8L 2x2
RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
Suitable for use in SnPb or Pb-free soldering processes.
½
Marking Information
For marking information, contact our sales representative
directly or through a Richtek distributor located in your
area.
Copyright
©
2014 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS9041F-03
November 2014
www.richtek.com
1
RT9041F
Typical Application Circuit
RT9041F
V
IN
1V to 5.5V
8
C
IN
10µF
VIN
VOUT 1
R1
ADJ
V
DD
3V to 5.5V
C
VDD
0.1µF
6 VDD
Chip Enable 5
EN
PGOOD 3
GND
4, 9 (Exposed pad)
R3
100k
2
R2
C
OUT
10µF
V
OUT
Function Pin Description
Pin No.
1
2
3
Pin Name
VOUT
ADJ
PGOOD
Output Voltage.
Output Voltage Adjust Pin. Set the output voltage by the internal feedback
resistors when ADJ is ground. If external feedback resistors is used,
V
OUT
= V
REF
x (R1 + R2)/R2.
Power Good Open Drain Output.
Ground. The exposed pad must be soldered to a large PCB and connected to
GND for maximum power dissipation.
Chip Enable (Active-High).
Supply Voltage of Control Circuitry.
No Internal Connection.
Power Input.
Pin Function
4, 9 (Exposed pad) GND
5
6
7
8
EN
VDD
NC
VIN
Function Block Diagram
VIN
OCP
VOUT
Driver
V
IN
+
-
Error
Amplifier
OTP
EN
VDD
UVLO
0.8V
-
Mode
ADJ
PGOOD
0.7V
+
GND
Copyright
©
2014 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
2
DS9041F-03
November 2014
RT9041F
Absolute Maximum Ratings
(Note 1)
6V
6V
6V
0.833VW
120°C/W
Bias Supply Input Voltage, VDD ---------------------------------------------------------------------------------------
Supply Input Voltage, VIN -----------------------------------------------------------------------------------------------
Other Input/Output Pins -------------------------------------------------------------------------------------------------
Power Dissipation, P
D
@ T
A
= 25°C
WDFN-8L 2x2 --------------------------------------------------------------------------------------------------------------
Package Thermal Resistance (Note 2)
WDFN-8L 2x2,
θ
JA
---------------------------------------------------------------------------------------------------------
WDFN-8L 2x2,
θ
JC
--------------------------------------------------------------------------------------------------------- 8.2°C/W
Lead Temperature (Soldering, 10 sec.) ------------------------------------------------------------------------------- 260°C
Junction Temperature ----------------------------------------------------------------------------------------------------- 150°C
Storage Temperature Range --------------------------------------------------------------------------------------------
−
65°C to 150°C
ESD Susceptibility (Note 3)
HBM (Human Body Model) ---------------------------------------------------------------------------------------------- 2kV
(Note 4)
3V to 5.5V
1V to 5.5V
−
40°C to 125°C
−
40°C to 85°C
Recommended Operating Conditions
Bias Supply Input Voltage, VDD ---------------------------------------------------------------------------------------
Supply Input Voltage, VIN -----------------------------------------------------------------------------------------------
Junction Temperature Range --------------------------------------------------------------------------------------------
Ambient Temperature Range --------------------------------------------------------------------------------------------
Electrical Characteristics
(V
IN
= 1.8V, I
LOAD
= 1mA, C
OUT
= 10μF, T
A
= 25°C unless otherwise specified)
Parameter
Input
Symbol
Test Conditions
Min
0.8
--
Typ
--
2.7
1
160
1
Max
2.5
--
5
250
5
Unit
V
V
A
A
A
Adjustable Output Voltage Range V
OUT
Bias Input Under Voltage Lockout V
UVLO
VIN Shutdown Current
Quiescent Current
VDD Shutdown Current
Regulator Characteristics
Line Regulation
Load Regulation
Fixed Output Voltage Accuracy
Reference Voltage
Dropout Voltage
Current Limit
Thermal-Shutdown
Thermal-Shutdown Hysteresis
V
OUT
/
V
IN
V
OUT
/
I
IN
V
OUT
V
REF
V
DROP
I
LIM
T
SD
T
SD
I
OUT
= 10mA, 1.5V < V
IN
< 5.5V,
V
IN
= V
OUT
+ 0.6V
V
IN
= V
OUT
+ 0.6V,
I
LOAD
= 1mA to 300mA
Short ADJ to GND, I
OUT
= 10mA
I
OUT
= 10mA
I
OUT
= 300mA, V
DD
V
OUT
2.1V
I
OUT
= 500mA, V
DD
V
OUT
2.1V
R
LOAD
= 0
3V < V
DD
< 5.5V
I
SHDN
I
Q
I
SHDN
1V < V
IN
< 5.5V, V
IN
= V
OUT
+ 0.6V
3V < V
DD
< 5.5V
3V < V
DD
< 5.5V
--
--
--
0.15
--
2
0.784
--
--
610
--
--
--
0.2
--
0.8
200
300
700
160
20
0.15
1
2
0.816
300
500
1400
--
--
%/V
%
%
V
mV
mA
°C
°C
Copyright
©
2014 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS9041F-03
November 2014
www.richtek.com
3
RT9041F
Parameter
ADJ
ADJ Pin Threshold
PGOOD Comparator
Comparator Threshold
Comparator Hysteresis
Logic and I/O
EN Input Voltage
EN Input Current
PGOOD Output Low Voltage
PGOOD Output High Leakage
Current
Dynamics
PGOOD Propagation Delay
t
PGOOD
Logic-High
Logic-Low
V
IH
V
IL
I
EN
V
EN
= 5V
PGOOD sinking 1mA
0 < V
PGOOD
< V
IN
Rising edge within 5% of regulation
level
1.6
--
--
--
1
--
--
12
--
--
--
0.8
--
0.1
1
V
A
V
A
V
HYST
% of regulated output voltage
(Note 5)
--
--
88
10
--
--
%
mV
--
0.2
--
V
Symbol
Test Conditions
Min
Typ
Max
Unit
1
--
5
ms
Note 1.
Stresses beyond those listed
“Absolute
Maximum Ratings” may cause permanent damage to the device. These are
stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in
the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions may
affect device reliability.
Note 2.
θ
JA
is measured at T
A
= 25°C on a high effective thermal conductivity four-layer test board per JEDEC 51-7.
θ
JC
is
measured at the exposed pad of the package.
Note 3.
Devices are ESD sensitive. Handling precaution is recommended.
Note 4.
The device is not guaranteed to function outside its operating conditions.
Note 5.
Guaranteed by Design.
Copyright
©
2014 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
www.richtek.com
4
DS9041F-03
November 2014
RT9041F
Typical Operating Characteristics
Output Voltage vs. Temperature
2.20
2.15
Reference Voltage vs. Temperature
0.84
0.83
Output Voltage (V)
2.10
2.05
2.00
1.95
1.90
1.85
1.80
-50
Reference Voltage (V)
0.82
0.81
0.80
0.79
0.78
0.77
V
DD
= 5V, V
IN
= 3.3V, V
OUT
= 2V, I
OUT
= 0mA
-25
0
25
50
75
100
125
0.76
-50
V
DD
= 5V, V
IN
= 3.3V, V
ADJ
= 0.8V, I
OUT
= 0mA
-25
0
25
50
75
100
125
Temperature (°C)
Temperature (°C)
Quiescent Current vs. Temperature
210
200
Current Limit vs. Temperature
0.90
0.85
Quiescent Current (μA)1
180
170
160
150
140
130
-50
Current Limit (A)
V
DD
= 5V, V
IN
= 3.3V, V
OUT
= 2V, I
OUT
= 0mA
190
0.80
0.75
0.70
0.65
0.60
0.55
0.50
V
DD
= 5V, V
IN
= 3.3V, V
OUT
= 2V, I
OUT
= 0mA
-50
-25
0
25
50
75
100
125
-25
0
25
50
75
100
125
Temperature (°C)
Temperature (°C)
Dropout Voltage vs. Output Current
600
500
1.6
1.5
EN Threshold Voltage vs. Temperature
Dropout Voltage (mV)
Threshold Voltage (V)
125°C
400
1.4
1.3
1.2
1.1
1.0
0.9
Rising
25°C
300
Falling
−40°C
200
100
0
0
100
200
300
V
DD
= 5V
400
500
0.8
-50
-25
0
25
V
DD
= 5V, V
OUT
= 1V
50
75
100
125
Output Current (mA)
Temperature (°C)
Copyright
©
2014 Richtek Technology Corporation. All rights reserved.
is a registered trademark of Richtek Technology Corporation.
DS9041F-03
November 2014
www.richtek.com
5