MC33761SNT1-030G [ONSEMI]
Ultra LowâNoise Low Dropout Voltage Regulator with 1.0 V ON/OFF Control; 超洛瓦????噪声，低压差稳压器与1.0 V ON / OFF控制
| 型号： | MC33761SNT1-030G |
| 厂家： | 
ONSEMI |
| 描述： | Ultra LowâNoise Low Dropout Voltage Regulator with 1.0 V ON/OFF Control |
| 文件： | 总13页 (文件大小：408K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
MC33761
Ultra Low−Noise Low
Dropout Voltage Regulator
with 1.0 V ON/OFF Control
The MC33761 is an Low DropOut (LDO) regulator featuring
excellent noise performances. Thanks to its innovative design, the
circuit reaches an impressive 40 mVRMS noise level without an
external bypass capacitor. Housed in a small SOT−23 5 leads−like
package, it represents the ideal designer’s choice when space and
noise are at premium. The absence of external bandgap capacitor
accelerates the response time to a wake−up signal and keeps it within
40 ms (in repetitive mode), making the MC33761 as a natural
candidate for portable applications.
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5
1
THIN SOT−23−5
SN SUFFIX
The MC33761 also hosts a novel architecture which prevents
excessive undershoots in the presence of fast transient bursts, as in any
bursting systems.
CASE 483
Finally, with a static line regulation better than −75 dB, it naturally
shields the downstream electronics against choppy lines.
Features
PIN CONNECTIONS AND
MARKING DIAGRAM
• Ultra−Low Noise: 150 nV/√Hz @ 100 Hz, 40 mVRMS
100 Hz−100 kHz Typical, I = 60 mA, Co = 1.0 mF
• Fast Response Time from OFF to ON: 40 ms Typical at a 200 Hz
Repetition Rate
out
5
1
2
V
V
out
in
GND
• Ready for 1.0 V Platforms: ON with a 900 mV High Level
• Nominal Output Current of 80 mA with a 100 mA Peak Capability
3
4
ON/OFF
NC
• Typical Dropout of 90 mV @ 30 mA, 160 mV @ 80 mA
• Ripple Rejection: 70 dB @ 1.0 kHz
• 1.5% Output Precision @ 25°C
(Top View)
= Device Code
= Assembly Location
= Year
Lxx
A
Y
W
G
• Thermal Shutdown
= Work Week
= Pb−Free Package
• V Available at 2.5 V, 2.8 V, 2.9 V, 3.0 V, 5.0 V
out
• Operating Range from −40 to +85°C
• Dual Version is Available as MC33762
(Note: Microdot may be in either location)
• Pb−Free Packages are Available
ORDERING INFORMATION
See detailed ordering and shipping information in the package
dimensions section on page 12 of this data sheet.
Applications
• Noise Sensitive Circuits: VCOs RF Stages, etc.
• Bursting Systems (TDMA Phones)
• All Battery Operated Devices
V
in
1
5
ON/
OFF
On/Off
Thermal
Shutdown
3
4
Band Gap
Reference
NC
V
out
*Current Limit
*Antisaturation Protection
*Load Transient Improvement
2
GND
Figure 1. Simplified Block Diagram
©
Semiconductor Components Industries, LLC, 2006
1
Publication Order Number:
July, 2006 − Rev. 8
MC33761/D
MC33761
PIN FUNCTION DESCRIPTIONS
Pin #
Pin Name
Function
Powers the IC
Description
1
2
3
V
in
A positive voltage up to 12 V can be applied upon this pin.
GND
The IC’s ground
ON/OFF
Shuts or wakes−up the IC
A 900 mV level on this pin is sufficient to start the IC. A 150 mV shuts it
down.
4
5
NC
None
It makes no arm to connect the pin to a known potential, like in a
pin−to−pin replacement case.
V
out
Delivers the output voltage
This pin requires a 1.0 mF output capacitor to be stable.
MAXIMUM RATINGS
Value
Min
−
Max
Rating
Pin #
Symbol
Unit
Power Supply Voltage
1
V
in
12
V
ESD Capability, HBM Model
All Pins
All Pins
−
−
−
1.0
200
kV
V
ESD Capability, Machine Model
−
−
Maximum Power Dissipation
NW Suffix, Plastic Package
Thermal Resistance Junction−to−Air
P
−
Internally Limited
W
D
R
−
210
°C/W
q
JA
Operating Ambient Temperature
Maximum Junction Temperature (Note 1)
Maximum Operating Junction Temperature (Note 2)
−
T
Jmax
T
−
−
−
−40 to +85
150
°C
°C
°C
A
T
125
J
Storage Temperature Range
−
T
stg
−
−60 to +150
°C
Stresses exceeding Maximum Ratings may damage the device. Maximum Ratings are stress ratings only. Functional operation above the
Recommended Operating Conditions is not implied. Extended exposure to stresses above the Recommended Operating Conditions may affect
device reliability.
ELECTRICAL CHARACTERISTICS
(For typical values T = 25°C, for min/max values T = −40°C to +85°C, max T = 125°C unless otherwise noted)
A
A
J
Characteristics
Pin #
Symbol
Min
Typ
Max
Unit
LOGIC CONTROL SPECIFICATIONS
Input Voltage Range
3
3
3
V
R
V
0
−
−
V
V
ON/OFF
ON/OFF
ON/OFF
in
ON/OFF Input Resistance (all versions)
250
−
kW
mV
ON/OFF Control Voltages (Note 3)
−
−
−
150
−
Logic Zero, OFF State, I = 50 mA
O
Logic One, ON State, I = 50 mA
900
O
CURRENTS PARAMETERS
Current Consumption in OFF State (all versions)
−
IQ
−
0.1
2.0
mA
OFF
OFF Mode Current: V = V + 1.0 V, I = 0, V
=
in
out
O
OFF
150 mV
Current Consumption in ON State (all versions)
−
−
−
IQ
−
−
180
800
180
−
−
mA
mA
ON
ON Mode Current: V = V + 1.0 V, I = 0, V = 3.5 V
ON
in
out
O
Current Consumption in ON State (all versions), ON Mode
IQ
SAT
Saturation Current: V = V − 0.5 V, No Output Load
in
out
Current Limit V = Vout
+ 1.0 V,
I
100
500
mA
in
nom
MAX
Output is brought to Vout
− 0.3 V (all versions)
nom
1. Internally limited by shutdown.
2. Specifications are guaranteed below this value.
3. Voltage slope should be greater than 2.0 mV/ms.
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MC33761
ELECTRICAL CHARACTERISTICS (continued)
(For typical values T = 25°C, for min/max values T = −40°C to +85°C, max T = 125°C unless otherwise noted)
A
A
J
Characteristics
Pin #
Symbol
Min
Typ
Max
Unit
OUTPUT VOLTAGES
V
+ 1.0 V < V < 6.0 V, T = 25°C, 1.0 mA < I < 80 mA
5
V
out
2.462
2.5
2.537
V
out
2.5 V
in
A
out
2.8 V
2.9 V
3.0 V
5.0 V
5
5
5
5
5
5
V
2.758
2.857
2.955
4.925
−1.5
2.8
2.9
3.0
5.0
X
2.842
2.943
3.045
5.075
+1.5
V
V
V
V
%
V
out
V
out
V
out
V
out
Other Voltages up to 5.0 V Available in 50 mV Increment Steps
+ 1.0 V < V < 6.0 V, T = −40°C to +85°C, 1.0 mA < I < 80 mA
V
out
V
V
out
2.425
2.5
2.575
out
2.5 V
in
A
out
2.8 V
2.9 V
3.0 V
5.0 V
5
5
5
5
5
V
2.716
2.813
2.91
2.8
2.9
3.0
5.0
X
2.884
2.987
3.090
5.150
+3.0
V
out
V
out
V
out
V
V
V
out
4.850
−3.0
Other Voltages up to 5.0 V Available in 50 mV Increment Steps
LINE AND LOAD REGULATION, DROPOUT VOLTAGES
Line Regulation (all versions)
V
out
%
5/1
5
Reg
−
−
−
−
20
40
mV
mV
mV
line
V
out
+ 1.0 V < V < 12 V, I = 80 mA
in out
Load Regulation (all versions)
= V + 1.0 V, C = 1.0 mF, I = 1.0 to 80 mA
Reg
load
V
in
out
out
out
Dropout Voltage (all versions) (Note 4)
5
5
5
V −V
−
−
−
90
140
160
150
200
250
I
I
I
= 30 mA
= 60 mA
= 80 mA
in out
out
out
out
V −V
in out
V −V
in out
DYNAMIC PARAMETERS
Ripple Rejection (all versions)
5/1
5
Ripple
−
−
−
−
−
−70
150
35
−
−
−
−
dB
V
in
= V + 1.0 V + 1.0 kHz 100 mVpp Sinusoidal Signal
out
Output Noise Density @ 1.0 kHz
nV/
√Hz
RMS Output Noise Voltage (all versions)
5
Noise
mV
ms
C
out
= 1.0 mF, I = 50 mA, F = 100 Hz to 1.0 MHz
out
Output Rise Time (all versions) C = 1.0 mF, I = 50 mA,
5
t
40
out
out
rise
10% of Rising ON Signal to 90% of Nominal V
out
THERMAL SHUTDOWN
Thermal Shutdown (all versions)
−
−
−
−
125
°C
4. V is brought to V − 100 mV.
out
out
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MC33761
DEFINITIONS
Load Regulation
Line Regulation
The change in output voltage for a change in output
current at a constant chip temperature.
The change in output voltage for a change in input voltage.
The measurement is made under conditions of low
dissipation or by using pulse technique such that the average
chip temperature is not significantly affected. One usually
distinguishes static line regulation or DC line regulation (a
DC step in the input voltage generates a corresponding step
in the output voltage) from ripple rejection or audio
susceptibility where the input is combined with a frequency
generator to sweep from a few hertz up to a defined
boundary while the output amplitude is monitored.
Dropout Voltage
The input/output differential at which the regulator output
no longer maintains regulation against further reductions in
input voltage. Measured when the output drops 100 mV
below its nominal value (which is measured at 1.0 V
differential value). The dropout level is affected by the chip
temperature, load current and minimum input supply
requirements.
Thermal Protection
Output Noise Voltage
Internal thermal shutdown circuitry is provided to protect
the integrated circuit in the event that the maximum junction
temperature is exceeded. When activated at typically 125°C,
the regulator turns off. This feature is provided to prevent
catastrophic failures from accidental overheating.
This is the integrated value of the output noise over a
specified frequency range. Input voltage and output current
are kept constant during the measurement. Results are
expressed in mVRMS.
Maximum Power Dissipation
The maximum total dissipation for which the regulator
will operate within its specs.
Maximum Package Power Dissipation
The maximum power package power dissipation is the
power dissipation level at which the junction temperature
reaches its maximum operating value, i.e. 125°C.
Depending on the ambient temperature, it is possible to
calculate the maximum power dissipation and thus the
maximum available output current.
Quiescent Current
The quiescent current is the current which flows through
the ground when the LDO operates without a load on its
output: internal IC operation, bias etc. When the LDO
becomes loaded, this term is called the Ground current. It is
actually the difference between the input current (measured
through the LDO input pin) and the output current.
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MC33761
CHARACTERIZATION CURVES
All curves taken with Vin = Vout + 1.0 V, Vout = 2.8 V, Cout = 1.0 mF
4.5
4.0
185
−40°C
25°C
3.5
3.0
2.5
2.0
1.5
1.0
85°C
180
175
170
165
0.5
0
0
20
40
60
80
100
−60 −40
−20
0
20
40
60
80
100
OUTPUT CURRENT (mA)
AMBIENT TEMPERATURE (°C)
Figure 2. Ground Current versus
Output Current
Figure 3. Quiescent Current versus
Temperature
200
150
100
2.805
2.800
2.795
2.790
2.785
85°C
85°C
25°C
40°C
−40°C
25°C
0°C
50
0
−20°C
−40°C
2.780
2.775
0
20
40
60
80
100
0
20
40
60
80
100
OUTPUT CURRENT (mA)
OUTPUT CURRENT (mA)
Figure 4. Dropout versus Output Current
Figure 5. Output Voltage versus
Output Current
180
160
140
120
100
80
80 mA
60 mA
30 mA
60
40
20
0
1.0 mA
60
−60 −40
−20
0
20
40
80
100
TEMPERATURE (°C)
Figure 6. Dropout versus Temperature
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MC33761
APPLICATION HINTS
Protections
Input Decoupling
As with any regulator, it is necessary to reduce the
dynamic impedance of the supply rail that feeds the
component. A 1.0 mF capacitor either ceramic or tantalum is
recommended and should be connected close to the
MC33761 package. Higher values will correspondingly
improve the overall line transient response.
The MC33761 hosts several protections, giving natural
ruggedness and reliability to the products implementing the
component. The output current is internally limited to a
maximum value of 180 mA typical while temperature
shutdown occurs if the die heats up beyond 125°C. These
values let you assess the maximum differential voltage the
device can sustain at a given output current before its
protections come into play.
Output Decoupling
Thanks to a novel concept, the MC33761 is a stable
component and does not require any specific Equivalent
Series Resistance (ESR) neither a minimum output current.
Capacitors exhibiting ESRs ranging from a few mW up to
3.0 W can thus safely be used. The minimum decoupling
value is 1.0 mF and can be augmented to fulfill stringent load
transient requirements. The regulator accepts ceramic chip
capacitors as well as tantalum devices.
The maximum dissipation the package can handle is given
by:
T
* T
Jmax
R
A
P
+
max
qJA
If T
is limited to 125°C, then the MC33761 can
Jmax
dissipate up to 470 mW @ 25°C. The power dissipated by
the MC33761 can be calculated from the following formula:
Noise Decoupling
) ) ǒV
Ǔ
Ptot + ǒVin
out Ǔ
I
(I
* V
I
out
out
gnd
in
Unlike other LDOs, the MC33761 is a true low−noise
regulator. Without the need of an external bypass capacitor,
it typically reaches the incredible level of 40 mVRMS overall
noise between 100 Hz and 100 kHz. To give maximum
insight on noise specifications, ON Semiconductor includes
spectral density graphics. The classical bypass capacitor
impacts the start−up phase of standard LDOs. However,
thanks to its low−noise architecture, the MC33761 operates
without a bypass element and thus offers a typical 40 ms
start−up phase.
or
Ptot ) V
I
out
out
Vin
+
max
I
) I
out
gnd
If a 80 mA output current is needed, the ground current is
extracted from the data−sheet curves: 4.0 mA @ 80 mA. For
a MC33761SNT1−28 (2.8 V) delivering 80 mA and
operating at 25°C, the maximum input voltage will then be
8.3 V.
Typical Applications
The following picture portrays the typical application of
the MC33761.
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MC33761
Dropout
Charge
5
4
Input
1
Output
Permanently
Enables the IC
When Closed
2
3
+
C3
1 mF
+
MC33761
C2
1.0 mF
R1
100 k
On/Off
Figure 7. A Typical Application Schematic
As for any low noise designs, particular care has to be
taken when tackling Printed Circuit Board (PCB) layout.
The figure below gives an example of a layout where stray
inductances/capacitances are minimized. This layout is the
basis for the MC33761 performance evaluation board. The
BNC connectors give the user an easy and quick evaluation
mean.
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MC33761
Understanding the Load Transient Improvement
The MC33761 features a novel architecture which allows
During this decreasing phase, the LDO stops the PNP bias
and one can consider the LDO asleep (Figure 8). If by
misfortune a current shot appears, the reaction time is
incredibly lengthened and a strong undershoot takes place.
This reaction is clearly not acceptable for line sensitive
devices, such as VCOs or other Radio−Frequency parts.
This problem is dramatically exacerbated when the output
current drops to zero rather than a few mA. In this later case,
the internal feedback network is the only discharge path,
accordingly lengthening the output voltage decay period
(Figure 9).
The MC33761 cures this problem by implementing a
clever design where the LDO detects the presence of the
overshoot and forces the system to go back to steady−state
as soon as possible, ready for the next shot. Figure 10 and 11
show how it positively improves the response time and
decreases the negative peak voltage.
the user to easily implement the regulator in burst systems
where the time between two current shots is kept very small.
The quality of the transient response time is related to
many parameters, among which the closed−loop bandwidth
with the corresponding phase margin plays an important
role. However, other characteristics also come into play like
the series pass transistor saturation. When a current
perturbation suddenly appears on the output, e.g. a load
increase, the error amplifier reacts and actively biases the
PNP transistor. During this reaction time, the LDO is in
open−loop and the output impedance is rather high. As a
result, the voltage brutally drops until the error amplifier
effectively closes the loop and corrects the output error.
When the load disappears, the opposite phenomenon takes
place with a positive overshoot. The problem appears when
this overshoot decays down to the LDO steady−state value.
Figure 8. A Standard LDO Behavior when the Load
Current Disappears
Figure 9. A Standard LDO Behavior when the Load
Current Appears in the Decay Zone
Figure 10. Without Load Transient Improvement
Figure 11. MC33761 with Load Transient Improvement
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MC33761
MC33761 Has a Fast Start−Up Phase
Thanks to the lack of bypass capacitor the MC33761 is
unacceptable level. MC33761 offers the best of both worlds
since it no longer includes a bypass capacitor and starts in
less than 40 ms typically (Repetitive at 200 Hz). It also
ensures a low−noise level of 40 mVRMS 100 Hz−100 kHz.
The following picture details the typical 33761 start−up
phase.
able to supply its downstream circuitry as soon as the OFF
to ON signal appears. In a standard LDO, the charging time
of the external bypass capacitor hampers the response time.
A simple solution consists in suppressing this bypass
element but, unfortunately, the noise rises to an
Figure 12. Repetitive Start−Up Waveforms
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MC33761
TYPICAL TRANSIENT RESPONSES
Figure 13. Output is Pulsed from 2.0 mA to 80 mA
Figure 14. Discharge Effects from 0 to 40 mA
Figure 15. Load Transient Improvement Effect
Figure 16. Load Transient Improvement Effect
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MC33761
TYPICAL TRANSIENT RESPONSES
250
200
150
100
V
T
C
= V + 1 .0V
= 25°C
RMS Noise, I = 50 mA:
20 Hz − 100 kHz: 27 mV
20 Hz − 1.0 MHz: 30 mV
in
out
O
A
= 1.0 mF
out
I
= 50 mA
10 mA
O
RMS Noise, I = 10 mA:
20 Hz − 100 kHz: 29 mV
20 Hz − 1.0 MHz: 31 mV
O
50
0
100
1,000
10,000
100,000 1,000,000
f, FREQUENCY (Hz)
Figure 17. MC33761 Typical Noise Density Performance
0
3.5
−10
I
= 1.0 mA
3.0
2.5
2.0
1.5
1.0
O
−20
−30
−40
−50
−60
−70
−80
10 mA
I
= 50 mA
O
80 mA
10 mA
V
T
C
= V + 1.0 V
= 25°C
in
O
A
0.5
0
−90
= 1.0 mF
20 mA
out
−100
100
1,000
10,000
100,000
1,000,000
100
1,000
10,000
100,000 1,000,000
f, FREQUENCY (Hz)
f, FREQUENCY (Hz)
Figure 18. MC33761 Typical Ripple Rejection
Performance
Figure 19. Typical Output Impedance plot
Cout = 1.0 mF, Vin = Vout + 1.0
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MC33761
ORDERING INFORMATION
†
Device
Specific Marking Code
Voltage Output
Package
Shipping
MC33761SNT1−025
MC33761SNT1−025G
Thin SOT−23−5
L25
L28
L29
L30
L50
2.5 V
Thin SOT−23−5
(Pb−Free)
MC33761SNT1−028
MC33761SNT1−028G
Thin SOT−23−5
2.8 V
2.9 V
3.0 V
5.0 V
Thin SOT−23−5
(Pb−Free)
MC33761SNT1−029
MC33761SNT1−029G
Thin SOT−23−5
3000 / Tape & Reel
Thin SOT−23−5
(Pb−Free)
MC33761SNT1−030
MC33761SNT1−030G
Thin SOT−23−5
Thin SOT−23−5
(Pb−Free)
MC33761SNT1−050
MC33761SNT1−050G
Thin SOT−23−5
Thin SOT−23−5
(Pb−Free)
†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
Specifications Brochure, BRD8011/D
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MC33761
PACKAGE DIMENSIONS
TSOP−5
CASE 483−02
ISSUE F
NOTES:
1. DIMENSIONING AND TOLERANCING PER
ASME Y14.5M, 1994.
2. CONTROLLING DIMENSION: MILLIMETERS.
3. MAXIMUM LEAD THICKNESS INCLUDES
LEAD FINISH THICKNESS. MINIMUM LEAD
THICKNESS IS THE MINIMUM THICKNESS
OF BASE MATERIAL.
4. DIMENSIONS A AND B DO NOT INCLUDE
MOLD FLASH, PROTRUSIONS, OR GATE
BURRS.
5. OPTIONAL CONSTRUCTION: AN
ADDITIONAL TRIMMED LEAD IS ALLOWED
IN THIS LOCATION. TRIMMED LEAD NOT TO
EXTEND MORE THAN 0.2 FROM BODY.
NOTE 5
5X
D
0.20 C A B
2X
2X
0.10
T
T
M
5
4
3
0.20
B
S
1
2
K
L
DETAIL Z
G
A
MILLIMETERS
DIM
A
B
MIN
3.00 BSC
1.50 BSC
MAX
DETAIL Z
J
C
D
G
H
J
K
L
M
S
0.90
0.25
0.95 BSC
1.10
0.50
C
SEATING
PLANE
0.05
H
0.01
0.10
0.20
1.25
0
0.10
0.26
0.60
1.55
T
10
3.00
_
_
2.50
SOLDERING FOOTPRINT*
1.9
0.074
0.95
0.037
2.4
0.094
1.0
0.039
0.7
0.028
mm
inches
ǒ
Ǔ
SCALE 10:1
*For additional information on our Pb−Free strategy and soldering
details, please download the ON Semiconductor Soldering and
Mounting Techniques Reference Manual, SOLDERRM/D.
ON Semiconductor and
are registered trademarks of Semiconductor Components Industries, LLC (SCILLC). SCILLC reserves the right to make changes without further notice
to any products herein. SCILLC makes no warranty, representation or guarantee regarding the suitability of its products for any particular purpose, nor does SCILLC assume any liability
arising out of the application or use of any product or circuit, and specifically disclaims any and all liability, including without limitation special, consequential or incidental damages.
“Typical” parameters which may be provided in SCILLC data sheets and/or specifications can and do vary in different applications and actual performance may vary over time. All
operating parameters, including “Typicals” must be validated for each customer application by customer’s technical experts. SCILLC does not convey any license under its patent rights
nor the rights of others. SCILLC products are not designed, intended, or authorized for use as components in systems intended for surgical implant into the body, or other applications
intended to support or sustain life, or for any other application in which the failure of the SCILLC product could create a situation where personal injury or death may occur. Should
Buyer purchase or use SCILLC products for any such unintended or unauthorized application, Buyer shall indemnify and hold SCILLC and its officers, employees, subsidiaries, affiliates,
and distributors harmless against all claims, costs, damages, and expenses, and reasonable attorney fees arising out of, directly or indirectly, any claim of personal injury or death
associated with such unintended or unauthorized use, even if such claim alleges that SCILLC was negligent regarding the design or manufacture of the part. SCILLC is an Equal
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P.O. Box 5163, Denver, Colorado 80217 USA
Phone: 303−675−2175 or 800−344−3860 Toll Free USA/Canada
Fax: 303−675−2176 or 800−344−3867 Toll Free USA/Canada
Email: orderlit@onsemi.com
Japan: ON Semiconductor, Japan Customer Focus Center
2−9−1 Kamimeguro, Meguro−ku, Tokyo, Japan 153−0051
Phone: 81−3−5773−3850
For additional information, please contact your
local Sales Representative.
MC33761/D
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