RT9194 [RICHTEK]
Low-Dropout Linear Regulator Controller with PGOOD Indication; 低压差线性稳压器控制器的PGOOD指示型号: | RT9194 |
厂家: | RICHTEK TECHNOLOGY CORPORATION |
描述: | Low-Dropout Linear Regulator Controller with PGOOD Indication |
文件: | 总10页 (文件大小:222K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
RT9194
Low-Dropout Linear Regulator Controller with PGOOD
Indication
General Description
Features
z 4.5V to 13.5V Operation Voltage
z High Accuracy 2% 0.8V Voltage Reference
z Quick Transient Response
The RT9194 is a low-dropout voltage regulator controller
with a specific PGOOD indicating scheme, it acts as a
power supervisor of the power regulated. The part could
drive an external N-Channel MOSFET for various
applications accordingly; especially, the part is operated
with VCC power ranging from 4.5V to 13.5V. With such a
topology, it's with advantages of flexible and cost-effective.
The part comes to a small footprint package of SOT-23-6.
z Power Good Indicator with Delay
z Enable Control
z Compliant with Intel “Grantsdale Chipset Platform
Design Guide” Specification
z Small Footprint Package SOT-23-6
z RoHS Compliant and 100% Lead (Pb)-Free
Ordering Information
Applications
RT9194
z Special Designed for Intel® Grantsdale platform
Package Type
E : SOT-23-6
FSB_VTT power regulation
z Processor Power-Up Sequening
Operating Temperature Range
P : Pb Free with Commercial Standard
G : Green (Halogen Free with Commer-
cial Standard)
z Notebook and laptop PC
z Other Power regulation with Power Good indication.
Note :
Pin Configurations
RichTek Pb-free and Green products are :
`RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
(TOP VIEW)
VCC DRI PGOOD
`Suitable for use in SnPb or Pb-free soldering processes.
`100%matte tin (Sn) plating.
6
1
5
2
4
3
Marking Information
EN GND
FB
For marking information, contact our sales representative
directly or through a RichTek distributor located in your
area, otherwise visit our website for detail.
SOT-23-6
Note : There is no pin1 indicator on top mark for SOT-23-6
type, and pin 1 will be lower left pin when reading top mark
from left to right.
Typical Application Circuit
V
V
IN
CC
Ccc
Chip Enable
1
6
5
EN
VCC
DRI
C
IN
2
3
RT9194
Q1
GND
FB
R
PGOOD
4
V
PGOOD
OUT
R1
C
OUT
PGOOD
R2
R1+R2
R2
VOUT = 0.8×
DS9194-08 March 2007
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1
RT9194
Test Circuit
V
CC
V
IN
12V
Ccc
1uF
Chip Enable
C
100uF
IN
EN
VCC
DRI
RT9194
Q1
PHD3055
GND
FB
100k
V
PGOOD
OUT
R
PGOOD
C
R1
1k
OUT
100uF
PGOOD
R2
2k
R1+R2
VOUT = 0.8×
R2
Figure 1. Typical Test Circuit
V
CC
12V
Ccc
1uF
Chip Enable
5V
EN
VCC
DRI
RT9194
V
A
DRI
GND
FB
V
PGOOD
FB
C
FB
V
= 1V for current sink at DRI
FB
V
= 0.6V for current source at DRI
FB
Figure 2. DRI Source/Sink Current Test Circuit
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RT9194
Functional Pin Description
Pin Name
Pin No.
Pin Function
EN
1
2
3
4
5
6
Chip Enable (Active High)
GND
FB
Ground
Output Voltage Feedback
Power Good Open Drain Output
Driver Output
PGOOD
DRI
VCC
Power Supply Input
Function Block Diagram
EN
VCC
PGOOD
GND
Reference
Voltage
0.8V
0.7V
+
DRI
-
Driver
+
-
3ms
Delay
FB
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RT9194
Absolute Maximum Ratings (Note 1)
z Supply Input Voltage, VCC ------------------------------------------------------------------------------------------- 15V
z Enable Voltage --------------------------------------------------------------------------------------------------------- 7V
z PowerGood Output Voltage ---------------------------------------------------------------------------------------- 7V
z Power Dissipation, PD @ TA = 25°C
SOT-23-6 ---------------------------------------------------------------------------------------------------------------- 0.4W
z Package Thermal Resistance
SOT-23-6, θJA ----------------------------------------------------------------------------------------------------------- 250°C/W
z Lead Temperature (Soldering, 10 sec.)--------------------------------------------------------------------------- 260°C
z Junction Temperature ------------------------------------------------------------------------------------------------- 150°C
z Storage Temperature Range ---------------------------------------------------------------------------------------- −65°C to 150°C
z ESD Susceptibility (Note 2)
HBM (Human Body Mode) ------------------------------------------------------------------------------------------ 2kV
MM (Machine Mode) -------------------------------------------------------------------------------------------------- 200V
Recommended Operating Conditions (Note 3)
z Supply Input Voltage, VCC ------------------------------------------------------------------------------------------- 4.5V to 13.5V
z Enable Voltage --------------------------------------------------------------------------------------------------------- 0V to 5.5V
z Junction Temperature Range---------------------------------------------------------------------------------------- −40°C to 125°C
z Ambient Temperature Range---------------------------------------------------------------------------------------- −40°C to 85°C
Electrical Characteristics
(VCC = 5V/12V, TA = 25°C, unless otherwise specified)
Parameter
Symbol
Test Conditions
input range
Min
Typ
Max Units
V
Operation Voltage Range
V
CC
V
CC
V
CC
V
CC
V
CC
V
CC
V
CC
V
CC
V
CC
V
CC
4.5
4.0
--
--
4.2
0.2
0.3
--
13.5
4.5
--
V
V
CC
POR Threshold
POR Hysteresis
rising
falling
V
V
CC
Supply Current
= 12V
--
0.8
--
mA
mA
mA
V
Driver Source Current
Driver Sink Current
= 12V, V
= 12V, V
= 12V, V
= 6V
= 6V
= 5V
5
DRI
DRI
DRI
5
--
--
Reference Voltage (V
)
0.784 0.8 0.816
FB
Reference Line Regulation (V
Amplifier Voltage Gain
PSRR at 100Hz, No Load
Power Good
)
= 4.5V to 15V
= 12V, no load
= 12V, no load
--
--
3
70
--
6
--
--
mV
dB
dB
FB
50
Rising Threshold
Hysteresis
V
CC
V
CC
V
CC
V
CC
V
CC
= 12V
--
--
--
1
90
15
0.2
3
--
--
%
%
= 12V
Sink Capability
= 12V @ 1mA
= 12V
0.4
10
--
V
Delay Time
ms
us
Falling Delay
= 12V
--
15
To be Continued
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RT9194
Parameter
Chip Enable
Test Conditions
Min
Typ
Max Units
EN Rising Threshold
EN Hysteresis
V
CC
V
CC
V
CC
= 12V
= 12V
--
--
--
0.7
30
--
--
--
5
V
mV
uA
Standby Current
= 12V, V = 0V
EN
Note 1. Stresses listed as the above "Absolute Maximum Ratings" may cause permanent damage to the device. These are for
stress ratings. 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 for extended
periods may remain possibility to affect device reliability.
Note 2. Devices are ESD sensitive. Handling precaution recommended.
Note 3. The device is not guaranteed to function outside its operating conditions.
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RT9194
Typical Operating Characteristics
Feedback Voltage vs. Temperature
Quiescent Current vs. Temperature
0.9
0.85
0.8
0.5
0.49
0.48
0.47
0.46
0.75
0.7
VIN = 1.5V, VCC = 12V, RPGOOD = 100k
CIN = COUT = 100uF, R1 = 1k, R2 = 2k
VIN = 1.5V, VCC = 12V, RPGOOD = 100k
CIN = COUT = 100uF, R1 = 1k, R2 = 2k
0.45
-50
-25
0
25
50
75
100
125
-50
-25
0
25
50
75
100
125
(°C)
Temperature
(°C)
Temperature
DRI Source Current vs. Temperature
DRI Sink Current vs. Temperature
60
55
50
45
40
35
30
27
24
21
18
15
12
VFB = 1V, VCC = 12V, VDRI = 6V
-50 -25 25 50
VFB = 0.6V, VCC = 12V, VDRI = 6V
-50 -25 25 50
0
75
100
125
0
75
100
125
(°C)
Temperature
(°C)
Temperature
Sink Current vs. DRI Voltage
PGOOD Delay Time vs. Temperature
4
3.5
3
25
20
15
10
5
VIN = 1.5V, VCC = 12V
RPGOOD = 100k
R1 = 1k, R2 = 2k
2.5
2
TA = 25°C
2.5 3
1.5
0
-50
-25
0
25
50
75
100
125
0
0.5
1
1.5
2
(°C)
Temperature
DRI Voltage (V)
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RT9194
PGOOD Delay Time
PGOOD Delay Time
VCC = 12V, ILOAD = 1A
IN = COUT = 100uF
VCC = 12V, CIN = COUT = 100uF, ILOAD = 100mA
C
VOUT
VOUT
ILoad (A)
VPGOOD
VPGOOD
VEN (V)
VEN (V)
Time (500us/Div)
Time (500us/Div)
PGOOD Off
Enable Threshold Voltage vs. Temperature
1
VCC = 12V
CIN = COUT = 100uF
VIN = 1.5V, VCC = 12V, RPGOOD = 100kΩ
VOUT
CIN = COUT = 100uF, R1 = 1k, R2 = 2k
0.95
0.9
0.85
0.8
Turn on
ILoad (A)
Turn off
0.75
0.7
VPGOOD
VEN (V)
0.65
0.6
-50
-25
0
25
50
75
100
125
Time (50us/Div)
Temperature
(°C)
Load Transient Response
Line Transient Response
VIN = 2.5V, VOUT = 1.2V
CIN = COUT = 100uF
VIN = 1.5V to 2.5V, ILOAD = 100mA
IN = 2.2uF, COUT = 100uF
C
20
0
10
0
-20
-10
5
0
2.5
1.5
Time (250us/Div)
Time (100us/Div)
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RT9194
Application Information
Capacitors Selection
the output voltage decay rate. Drive the EN pin high to
turn on the device again.
Careful selection of the external capacitors for RT9194 is
highly recommended in order to remain high stability and
performance.
Under Voltage Protection
RT9194 equips the VOUT under-voltage (UV) protection
function. The UV protection circuits will start monitoring
the power status after the PGOOD pin goes high. If the
output voltage drops to below 75% of its setting value,
the PGOOD and DRI pins will be pulled low and latch
RT9194. The UV latch status will be released only when
VCC or Enable pin goes low and returns high again, which
will also cause RT9194 to re-activate.
Regarding the supply voltage capacitor, connecting a
capacitor which is 1μF between VCC and ground is a must.
The capacitor improves the supply voltage stability to
provide chip normally operating.
Regarding the input capacitor, connecting a capacitor which
100μF between VIN and ground is recommended to
increase stability. With large value of capacitance could
result in better performance for both PSRR and line
transient response.
MOSFET Selection
The RT9194 are designed to driver external N-Channel
MOSFET pass element. MOSFET selection criteria
include threshold voltage VGS (VTH), maximum
continuous drain current ID, on-resistance RDS(ON)
,maximum drain-to-source voltage VDS and package
When driving external pass element, connecting a
capacitor 100μF between VOUT and ground is
recommended for stability. With larger capacitance can
reduce noise and improve load transient response and
PSRR.
thermal resistance θ(JA)
.
Output Voltage Setting
The most critical specification is the MOSFET RDS(ON).
Calculate the required RDS(ON) from the following formula:
The RT9194 develop a 0.8V reference voltage; especially
suit for low voltage application. As shown in application
circuit, the output voltage could easy set the output
voltage by R1 & R2 divider resistor.
V
− V
IN
OUT
NMOSFETR
=
DS(ON)
I
LOAD
For example, the MOSFET operate up to 2A when the
input voltage is 1.5V and set the output voltage is 1.2V,
RON = (1.5V-1.2V) / 2A = 150mΩ, the MOSFET's
RON have to select lower than 150mΩ.APhilip PHD3055E
MOSFET with an RDS(ON) of 120mΩ(typ.) is a close
match.
Power Good Function
The RT9194 has the power good function with delay. The
power good output is an open drain output. Connect a
100kΩ pull up resistor to VOUT to obtain an output voltage.
When the output voltage arrive 90% of normal value the
power good will output voltage with 3ms delay time.
And carry on consider the thermal resistance from
junction to ambient θ(JA) of the MOSFET's package. The
power dissipation calculate by :
When the output voltage falling arrive 75% of normal value
the power good will turn off with less than 1ms delay time.
But, there are two exceptions. One is the enable pull low
the power good will turn off quickly. The second is the
VCC falling arrive POR value (4V typ.) the power good
also will turn off quickly.
PD = (VIN − VOUT) x ILOAD
The thermal resistance from junction to ambient θ(JA)
calculate by :
(T − T )
J
A
θ
=
(JA)
P
D
In this example, PD = (1.5V − 1.2V) x 2A = 0.6W. The
PHD3055E's θ(JA) is 75°C/W for itsD-PAK package, which
translates to a 45°C temperature rise above ambient. The
package provides exposed backsides that directly transfer
heat to the PCB board.
Chip Enable Operation
Pull the EN pin low to drive the device into shutdown mode.
During shutdown mode, the standby current drops to
5μA(MAX). The external capacitor and load current determine
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RT9194
PNP Transistor Selection
The RT9194 could driver the PNP transistor to sink output current. PNP transistor selection criteria include DC current
gain hFE, threshold voltage VEB, collector-emitter voltage VCE, maximum continues collector current IC, package thermal
resistance θ(JA).
For example, the PNP transistor operates sink current up to 0.5A when the input voltage is 1.5V and set the output
voltage is 1.2V. As show in Figure 3. A KSB772 PNP transistor, the VCE = 1.2V, VBE = -1V, IC = 0.5A, IB = 0.5/160 ]
3.125mA, when the DRI pin voltage is 0.2V could sink 6.8mA(MAX) is a close match.
Sink Current vs. DRI Voltage
25
V
IN
20
15
10
5
PGOOD
R
C
IN
VCC
Q1
DRI
V
CC
Ccc
PGOOD
V
PGOOD
GND
EN
OUT
RT9194
Chip Enable
FB
C
R1
R2
OUT
Q2
TA = 25°C
0
0
0.5
1
1.5
2
2.5
3
Figure 3
DRI Voltage (V)
Figure 4
Layout Considerations
There are three critical layout considerations. One is the divider resistors should be located to RT9194 as possible to
avoid inducing any noise. The second is capacitors place. The CIN and COUT have to put at near the NMOS for improve
performance. The third is the copper area for pass element. We have to consider when the pass element operating
under high power situation that could rise the junction temperature. In addition to the package thermal resistance limit,
we could add the copper area to improve the power dissipation. As show in Figure 5 and Figure 6.
V
IN
V
IN
PGOOD
C
IN
VCC
Q1
DRI
V
GND
CC
Ccc
R
PGOOD
PGOOD
GND
EN
V
OUT
PGOOD
FB
V
RT9194
CC
Chip Enable
FB
R1
R2
C
OUT
V
OUT
EN
GND
Figure 5
Figure 6
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RT9194
Outline Dimension
H
D
L
C
A
B
b
A1
e
Dimensions In Millimeters
Dimensions In Inches
Symbol
Min
Max
Min
Max
A
A1
B
0.889
0.000
1.397
0.250
2.591
2.692
0.838
0.080
0.300
1.295
0.152
1.803
0.560
2.997
3.099
1.041
0.254
0.610
0.031
0.000
0.055
0.010
0.102
0.106
0.033
0.003
0.012
0.051
0.006
0.071
0.022
0.118
0.122
0.041
0.010
0.024
b
C
D
e
H
L
SOT-23-6 Surface Mount Package
Richtek Technology Corporation
Headquarter
Richtek Technology Corporation
Taipei Office (Marketing)
5F, No. 20, Taiyuen Street, Chupei City
Hsinchu, Taiwan, R.O.C.
8F, No. 137, Lane 235, Paochiao Road, Hsintien City
Taipei County, Taiwan, R.O.C.
Tel: (8863)5526789 Fax: (8863)5526611
Tel: (8862)89191466 Fax: (8862)89191465
Email: marketing@richtek.com
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DS9194-08 March 2007
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