NCP623
Ultra Low Noise
150 mA Low Dropout
Voltage Regulator with
ON/OFF Control
Housed in a Micro8t or QFN6 package, the NCP623 delivers up to
150 mA where it exhibits a typical 180 mV dropout. With an
incredible noise level of 25
mVRMS
(over 100 Hz to 100 kHz, with a
10 nF bypass capacitor), the NCP623 represents the ideal choice for
sensitive circuits, especially in portable applications where noise
performance and space are premium. The NCP623 also excels in
response time and reacts in less than 25
ms
when receiving an OFF to
ON signal (with no bypass capacitor).
Due to a novel concept, the NCP623 accepts output capacitors without
any restrictions regarding their Equivalent Series Resistance (ESR) thus
offering an obvious versatility for immediate implementation.
With a typical DC ripple rejection better than −90 dB (−70 dB @
1.0 kHz), it naturally shields the downstream electronics against
choppy power lines.
Additionally, thermal shutdown and short−circuit protection
provide the final product with a high degree of ruggedness.
Features
http://onsemi.com
MARKING
DIAGRAMS
8
Micro8
DM SUFFIX
CASE 846A
1
1
NCP6
23yy
ALYW
XXX
AYW
1
QFN6, 3X3
MN SUFFIX
CASE 488AE
•
Very Low Quiescent Current 170
mA
(ON, no load), 100 nA
•
•
•
•
•
•
•
•
•
•
(OFF, no load)
Very Low Dropout Voltage, Typical Value is 137 mV at an Output
Current of 100 mA
Very Low Noise with External Bypass Capacitor (10 nF),
Typically 25
mVrms
over 100 Hz to 100 kHz
Internal Thermal Shutdown
Extremely Tight Line Regulation Typically −90 dB
Ripple Rejection −70 dB @ 1.0 kHz
Line Transient Response: 1.0 mV for
DV
in
= 3.0 V
Extremely Tight Load Regulation, Typically 20 mV at
DI
out
= 150 mA
Multiple Output Voltages Available
Logic Level ON/OFF Control (TTL−CMOS Compatible)
ESR can vary from 0 to 3.0
W
XXX
yy
A
L
Y
W
= Specific Device Code
= Voltage Option
= Assembly Location
= Wafer Lot
= Year
= Work Week
PIN CONNECTIONS
Bypass
NC
NC
ON/OFF
1
2
3
4
Micro8
(Top View)
8
7
6
5
V
OUT
GND
GND
V
IN
Applications
•
All Portable Systems, Battery Powered Systems, Cellular
Telephones, Radio Control Systems, Toys and Low Voltage Systems
V
IN
GND
V
OUT
1
2
3
6
5
4
ON/OFF
GND
Bypass
QFN6
(Top View)
ORDERING INFORMATION
See detailed ordering and shipping information on page 12 of
this data sheet.
©
Semiconductor Components Industries, LLC, 2004
1
August, 2004 − Rev. 0
Publication Order Number:
NCP623/D
NCP623
V
IN
On/Off
ON/OFF
Thermal
Shutdown
Bypass
Band Gap
Reference
V
OUT
* Current Limit
* Antisaturation
*
Protection
GND
GND
Figure 1. NCP623 Block Diagram
MAXIMUM RATINGS
Rating
Power Supply Voltage
Power Dissipation and Thermal Resistance
Maximum Power Dissipation
Case 488AE (QFN6, 3x3) MN Suffix
Thermal Resistance, Junction−to−Air
Thermal Resistance, Junction−to−Case
Case 846A (Micro8) DM Suffix
Thermal Resistance, Junction−to−Air
Thermal Resistance, Junction−to−Case
Operating Ambient Temperature Range
Maximum Junction Temperature
Storage Temperature Range
ESD Protection − Human Body Model
Machine Model
Symbol
V
in
P
D
R
qJA
R
qJC
R
qJA
R
qJC
T
A
T
Jmax
T
stg
V
ESD
Value
12
Internally Limited
161
19
240
105
−40 to +85
150
−60 to +150
2000
200
°C
°C
°C
V
Unit
V
W
°C/W
Maximum ratings are those values beyond which device damage can occur. Maximum ratings applied to the device are individual stress limit
values (not normal operating conditions) and are not valid simultaneously. If these limits are exceeded, device functional operation is not implied,
damage may occur and reliability may be affected.
http://onsemi.com
2
NCP623
ELECTRICAL CHARACTERISTICS
(For typical values T
A
= 25°C, for min/max values T
A
= −40°C to +85°C, Max T
J
= 150°C)
Characteristics
Symbol
Min
Typ
Max
Unit
CONTROL ELECTRICAL CHARACTERISTICS
Input Voltage Range
ON/OFF Input Current (All versions)
V
ON/OFF
= 2.4 V
ON/OFF Input Voltages (All versions)
Logic “0”, i.e. OFF State
Logic “1”, i.e. ON State
V
ON/OFF
I
ON/OFF
−
V
ON/OFF
−
2.2
−
−
0.3
−
mA
−
IQ
ON
−
IQ
SAT
−
I
MAX
175
V
out
3.23
3.92
4.90
V
out
3.18
3.86
4.83
3.3
4.0
5.0
3.42
4.14
5.17
3.3
4.0
5.0
3.37
4.08
5.1
V
210
−
V
900
1400
mA
170
200
mA
0.1
2.0
mA
2.5
−
V
0
−
V
in
V
mA
CURRENTS PARAMETERS
Current Consumption in OFF State (All versions)
OFF Mode Current: V
in
= V
out
+ 1.0 V, I
out
= 0 mA
Current Consumption in ON State (All versions)
ON Mode Sat Current: V
in
= V
out
+ 1.0 V, I
out
= 0 mA
Current Consumption in Saturation ON State (All versions)
ON Mode Sat Current: V
in
= V
out
− 0.5 V, I
out
= 0 mA
Current Limit V
in
= V
out
+ 1.0 V, (All versions)
Output Short−circuited (Note 1)
V
in
= V
out
+ 1.0 V, T
A
= 25°C, 1.0 mA < I
out
< 150 mA
3.3 Suffix
4.0 Suffix
5.0 Suffix
V
in
= V
out
+ 1.0 V, −40°C < T
A
< 85°C
3.3 Suffix
4.0 Suffix
5.0 Suffix
IQ
OFF
LINE AND LOAD REGULATION, DROPOUT VOLTAGES
Line Regulation (All versions)
V
out
+ 1.0 V < V
in
< 12 V, I
out
= 60 mA
Load Regulation (All versions)
V
in
= V
out
+ 1.0 V
I
out
= 1.0 to 60 mA
I
out
= 1.0 to 100 mA
I
out
= 1.0 to 150 mA
I
out
= 10 mA
I
out
= 100 mA
I
out
= 150 mA
Reg
line
−
Reg
load
−
−
−
V
in
− V
out
−
−
−
30
137
180
90
230
260
8.0
15
20
25
35
45
mV
2.0
10
mV
mV
Dropout Voltage (All versions)
DYNAMIC PARAMETERS
Ripple Rejection (All versions)
V
in
= V
out
+ 1.0 V, V
pp
= 1.0 V, f = 1.0 kHz, I
out
= 60 mA
Line Transient Response
V
in
= V
out
+ 1.0 V to V
out
+ 4.0 V, I
out
= 60 mA, d(V
in
)/dt = 15 mV/ms
Output Noise Voltage (All versions)
C
out
= 1.0
µF,
I
out
= 60 mA, f = 100 Hz to 100 kHz
C
bypass
= 10 nF
C
bypass
= 1.0 nF
C
bypass
= 0 nF
Output Noise Density
C
out
= 1.0
µF,
I
out
= 60 mA, f = 1.0 kHz
Output Rise Time (All versions)
C
out
= 1.0
µF,
I
out
= 30 mA, V
ON/OFF
= 0 to 2.4 V
1% of ON/OFF Signal to 99% of Nominal Output Voltage
Without Bypass Capacitor
With C
bypass
= 10 nF
V
RMS
−
−
−
V
N
−
t
r
µs
ms
°C
230
−
25
40
65
−
−
−
nV/
√Hz
dB
60
−
70
1.0
−
mV
−
µVrms
−
−
40
1.1
−
−
THERMAL SHUTDOWN
Thermal Shutdown (All versions)
−
150
−
1. I
out
(Output Current) is the measured current when the output voltage drops below 0.3 V with respect to V
out
at I
out
= 30 mA.
http://onsemi.com
3
NCP623
DEFINITIONS
Load Regulation
− The change in output voltage for a
change in load current at constant chip temperature.
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), dropout voltage is affected
by junction temperature, load current and minimum input
supply requirements.
Output Noise Voltage
− The RMS AC voltage at the
output with a constant load and no input ripple, measured
over a specified frequency range.
Maximum Power Dissipation
− The maximum total
dissipation for which the regulator will operate within
specifications.
Quiescent Current
− Current which is used to operate the
regulator chip and is not delivered to the load.
Line Regulation
− The change in input voltage for a
change in the input voltage. The measurement is made under
conditions of low dissipation or by using pulse techniques
such that the average chip temperature is not significantly
affected.
Line Transient Response
− Typical over− and
undershoot response when input voltage is excited with a
given slope.
Thermal Protection
− Internal thermal shutdown
circuitry is provided to protect the integrated circuit in the
event that the maximum junction temperature is exceeded.
When activated, typically 150°C, the regulator turns off.
This feature is provided to prevent catastrophic failures from
accidental overheating.
Maximum Package Power Dissipation
− The maximum
package power dissipation is the power dissipation level at
which the junction temperature reaches its maximum value
i.e. 125°C. The junction temperature is rising while the
difference between the input power (V
CC
X I
CC
) and the
output power (V
out
X I
out
) is increasing.
Depending on ambient temperature, it is possible to
calculate the maximum power dissipation, maximum load
current or maximum input voltage (see Application Hints:
Protection).
The maximum power dissipation supported by the device
is a lot increased when using appropriate application design.
Mounting pad configuration on the PCB, the board material
and also the ambient temperature are affected the rate of
temperature rise. It means that when the I
C
has good thermal
conductivity through PCB, the junction temperature will be
“low” even if the power dissipation is great.
The thermal resistance of the whole circuit can be
evaluated by deliberately activating the thermal shutdown
of the circuit (by increasing the output current or raising the
input voltage for example).
Then you can calculate the power dissipation by
subtracting the output power from the input power. All
variables are then well known: power dissipation, thermal
shutdown temperature (150°C for NCP623) and ambient
temperature.
http://onsemi.com
4
NCP623
APPLICATION HINTS
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 NCP623 package. Higher values will correspondingly
improve the overall line transient response.
Output Decoupling
− Due to a novel concept, the
NCP623 is a stable component and does not require any
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.
Noise Performances
− Unlike other LDOs, the NCP623
is a true low−noise regulator. With a 10 nF bypass capacitor,
it typically reaches the incredible level of 25
mVRMS
overall
noise between 100 Hz and 100 kHz. To give maximum
insight on noise specifications, ON Semiconductor includes
spectral density graphics as well as noise dependency versus
bypass capacitor.
The bypass capacitor impacts the start−up phase of the
NCP623 as depicted by the data−sheet curves. A typical
1.0 ms settling time is achieved with a 10 nF bypass
capacitor. However, due to its low−noise architecture, the
NCP623 can operate without bypass and thus offers a typical
20
ms
start−up phase. In that case, the typical output noise
stays lower than 65
mVRMS
between 100 Hz − 100 kHz.
Protections
− The NCP623 hosts several protections,
conferring natural ruggedness and reliability to the products
implementing the component. The output current is
internally limited to a minimum of 175 mA while
temperature shutdown occurs if the die heats up beyond
150°C. These value lets you assess the maximum
differential voltage the device can sustain at a given output
current before its protections come into play.
The maximum dissipation the package can handle is given
by:
T
– T
A
P max
+
Jmax
R
qJA
If a 150 mA output current is needed, the ground current
is extracted from the data−sheet curves: 6.5 mA @ 150 mA.
For a NCP623NW28R2 (2.8 V), the maximum input voltage
will then be 6.48 V, a rather comfortable margin.
Typical Application
− The following figure portraits the
typical application for the NCP623 where both input/output
decoupling capacitors appear.
On/Off
6
C3
1.0
mF
1
5
4
C1
10 nF
NCP623
C2
1.0
mF
3
2
Input
Output
Figure 2. A Typical NCP623 Application with
Recommended Capacitor Values (QFN6)
Output
Input
8
C2
1.0
mF
1
C1
10 nF
7
6
5
C3
1.0
mF
4
On/Off
NCP623
2
3
NC NC
If T
Jmax
is internally limited to 150°C, then the NCP623 can
dissipate up to 595 mW @ 25°C.
The power dissipated by the NCP623 can be calculated
from the following formula:
Ptot
+
V
@
I
(I )
)
V
*
Vout
@
I out
in gnd out
in
Figure 3. A Typical NCP623 Application with
Recommended Capacitor Values (Micro8)
or
Vin max
+
Ptot
)
Vout
@
I out
I
)
I out
gnd
http://onsemi.com
5
京公网安备 11010802033920号
EEWORLD
