CMPWR280
1.5A SmartOR
TM
Dual Regulator with V
AUX
Drive
Features
•
•
•
•
•
•
•
•
•
•
•
Selects from 3 input voltages and provides 3.3V
output
Automatic selection of V
CC
, V
SBY
or V
AUX
Drive control signal for external V
AUX
switch
Glitch-free 3.3V output during supply transitions
Built-in hysteresis for supply selection
V
CC
regulates up to 1.5A output current
V
SBY
regulates up to 375mA output current
Foldback current limiting
Thermal shutdown with hysteresis
TO-263 standard and thin-body packages
Lead-free versions avilable
Product Description
The
California
Micro
Devices’
SmartOR
TM
CMPWR280 is a fully protected Dual-Input low-dropout
CMOS regulator that also provides the necessary con-
trol signal for driving an external auxiliary P-channel
MOSFET switch. The SmartOR
TM
device automatically
selects one of three possible inputs on a priority basis:
V
CC
(1.5A), V
SBY
(375mA) or V
AUX
via the drive signal
used to control an external switch.
V
CC
is given first priority. In the event of the V
CC
supply
being powered down, the device will automatically
deselect the V
CC
prior to regulator dropout and imme-
diately select V
SBY
(second priority) as its power
source.
If neither V
CC
nor V
SBY
are present the drive control
output will turn-on an external P-channel MOSFET
switch from an auxiliary 3.3V supply V
AUX
to V
OUT
.
All the necessary control circuitry needed to provide a
smooth and automatic transition between all three sup-
plies has been incorporated. This allows V
CC
to be
dynamically switched without loss of output voltage.
The CMPWR280 is internally protected against output
short-circuits, current overload and thermal overload.
The CMPWR280 is housed in both a standard, 5-lead
TO-263 package or a thin-body, 5-lead TO-263 pack-
age and is available with optional lead-free finishing.
Applications
•
•
•
•
Peripheral Component Interface (PCI) Adapter
Cards
Network Interface Cards (NICs)
Multiple Powered Systems
Systems with Standby Capabilities
Typical Application Circuit
V
AUX
3.3V
Simplified Electrical Schematic
V
SBY
V
CC
1.5A
V
CC/SBY
ENABLE
CC
S
W
A
UX
375mA
FDN338P
(Si2310DS)
Controller
V
SBY
5V
375mA
CMPWR280
V
SBY
1.5A
+
+
+
1
µ
F
C
IN2
V
CC
5V
-
Drive
V
OUT
V
CC
GND
V
OUT
+
C
OUT
10
µ
F
GND
V
DESELECT
4.1V
+
V
REF
3.3V
SBY
3.3V
400mA
-
Regulator Amp
V
OUT
DRIVE
+
1
µ
F
C
IN1
GND
©
2004 California Micro Devices Corp. All rights reserved.
08/16/04
430 N. McCarthy Blvd., Milpitas, CA 95035-5112
●
Tel: 408.263.3214
●
Fax: 408.263.7846
●
www.calmicro.com
1
CMPWR280
PACKAGE / PINOUT DIAGRAM
Top View
VSBY
V
CC
GND
V
OUT
DRIVE
1
2
3
4
5
Top View
VSBY
V
CC
GND
V
OUT
DRIVE
1
2
3
4
5
5-pin TO-263
CMPWR280TO/TN
Note: These drawings are not to scale.
5-pin Thin TO-263
CMPWR280TA/TB
PIN DESCRIPTIONS
PIN(S)
1
NAME
V
SBY
.
DESCRIPTION
V
SBY
is the standby 5V supply power source, which is only selected on when V
CC
< V
CCDES
. If VSBY is
selected, the regulator can deliver a maximum of 375mA load current. Whenever V
SBY
exceeds both V
CC
and V
OUT
, it will be used to provide all the internal bias currents and any necessary regulator current.
V
CC
is the primary 5V power supply for the internal regulator. Whenever V
CC
exceeds V
CCSEL
(4.5V), the
internal regulator (up to 1500mA) will be enabled and deliver a fixed 3.3V at V
OUT
. When V
CC
falls below
V
CCDES
(4.1V typically) the regulator will be disabled.
Internal loading on this pin is typically 1.5mA when the regulator is enabled, which reduces to 0.2mA
whenever the regulator is disabled. If V
CC
falls below either the V
SBY
or V
OUT
voltage, the loading on
V
CC
will reduce to only a few microamperes.
During a V
CC
power up sequence, there will be an effective step increase in V
CC
line current when the
regulator is enabled. The amplitude of this step increase will depend on the dc load current and any cur-
rent required for charging/discharging the load capacitance. This line current transient will cause a volt-
age disturbance at the V
CC
pin proportional to the effective power supply source impedance being
delivered to the V
CC
input.
To prevent chatter during Select and Deselect transitions, a built-in hysteresis voltage of 400mV has
been incorporated. It is recommended that the power supply connected to the V
CC
input should have a
source impedance of less than 0.15Ω to minimize the chatter during the enabling/disabling of the regula-
tor.
GND is the negative reference for all voltages. The current that flows in the ground connection is very
low (typically 2.0mA) and has minimal variation over all load conditions.
V
OUT
is the regulator output voltage connection used to power the load. An output capacitor of ten
microfarads is used to provide the necessary phase compensation, thereby preventing oscillation. The
capacitor also helps to minimize the peak output disturbance during power supply changeover.
When both V
CC
and V
SBY
falls below V
OUT
, then V
OUT
will be used to provide the necessary quiescent
current for the internal reference circuits. This ensures excellent start-up characteristics for the regulator.
Drive is an active LOW logic output intended to be used as the control signal for driving an external P-
channel MOSFET switch whenever the regulator is disabled. This will allow the voltage at V
OUT
to be
powered from an auxiliary supply voltage (3.3V).
The Drive pin is pulled HIGH to V
CC
whenever the regulator is enabled, thus ensuring that the auxiliary
supply remains isolated during normal regulator operation.
2
V
CC
3
4
GND
V
OUT
5
DRIVE
©
2004 California Micro Devices Corp. All rights reserved.
2
430 N. McCarthy Blvd., Milpitas, CA 95035-5112
●
Tel: 408.263.3214
●
Fax: 408.263.7846
●
www.calmicro.com
08/16/04
CMPWR280
Ordering Information
PART NUMBERING INFORMATION
Standard Finish
Regulator
CMPWR280
CMPWR280
Pins
5
5
Package
TO-263
Thin TO-263
Ordering Part
Number
1
CMPWR280TO
CMPWR280TA
Part Marking
CMPWR280TO
CMPWR280TA
Lead-free Finish
Ordering Part
Number
1
CMPWR280TN
CMPWR280TB
Part Marking
CMPWR280TN
CMPWR280TB
Note 1: Parts are shipped in Tape & Reel form unless otherwise specified.
Specifications
ABSOLUTE MAXIMUM RATINGS
PARAMETER
ESD Protection (HBM)
Pin Voltages
V
CC
, V
SBY
, V
OUT
,
DRIVE
Storage Temperature Range
Operating Temperature Range
Ambient
Junction
Power Dissipation (See Note 1)
TO-263
Thin TO-263
RATING
+2000
[GND - 0.5] to [+6.0]
[GND - 0.5] to [V
CC
(V
SBY
)+ 0.5]
-40 to +150
0 to +70
0 to +150
Internally Limited
Internally Limited
UNITS
V
V
V
°C
°C
°C
W
W
Note 1: The maximum power dissipation of this device is internally limited by thermal shutdown circuitry. To achieve a power dissipa-
tion of 3.0 watts, a case-to-ambient thermal resistance of 25°C/W must be provided. This will typically require dedicated
heatsinking ability of the printed circuit board. For more details, please see the Typical Thermal Characteristics section.
STANDARD OPERATING CONDITIONS
PARAMETER
V
CC,
V
SBY
Input Voltage
Ambient Operating Temperature Range
C
EXT
RATING
4.75 to 5.25
0 to +70
10 +10%
UNITS
V
°C
µF
©
2004 California Micro Devices Corp. All rights reserved.
08/16/04
430 N. McCarthy Blvd., Milpitas, CA 95035-5112
●
Tel: 408.263.3214
●
Fax: 408.263.7846
●
www.calmicro.com
3
CMPWR280
Specifications (cont’d)
ELECTRICAL OPERATING CHARACTERISTICS
(NOTE 1)
SYMBOL
V
OUT
V
CCSEL
V
CCDES
V
CCHYST
I
OUT
I
SC
I
RCC
I
RSBY
V
R LOAD
PARAMETER
Regulator Output Voltage
Select Voltage
V
CC
Deselect Voltage
Hysteresis Voltage
Regulator Output Current
Short-circuit Output Current
V
CC
Pin Reverse Leakage
V
SBY
Pin Reverse Leakage
V
CC
Load Regulation
V
SBY
Load Regulation
V
R LINE
I
CC
I
SBY
I
GND
Line Regulation
V
CC
Supply Current
V
SBY
Supply Current
CONDITIONS
0mA < I
LOAD
< 1500mA (V
CC
)
0mA < I
LOAD
< 375mA (V
SBY
)
V
CC
Regulator Enabled
V
CC
Regulator Disabled
V
CC
Hysteresis, See Note 2
V
CC
Selected
V
SBY
Selected
V
CC
Selected
V
SBY
Selected
V
SBY
=5.0V; V
CC
= 0V
V
SBY
=0V; V
CC
= 5.0V
V
CC
selected, I
LOAD
=15mA to 1500mA
V
SBY
selected, I
LOAD
=5mA to 375mA
V
CC
=4.5 to 5.5V, I
LOAD
=5mA
V
CC
selected, I
OUT
=0mA
V
CCDES
> V
CC
> V
AUX
or V
OUT
V
SBY
selected, I
OUT
=0mA
1500
375
3.90
MIN
3.135
TYP
3.300
4.50
4.10
0.40
2500
750
800
200
x
10
x
10
MAX
3.465
4.70
UNITS
V
V
V
V
mA
mA
mA
mA
100
100
µA
µA
mV
mV
mV
30
30
5
1.5
0.1
1.5
0.2
1.5
1.8
5
0.5
x
5.0
3.0
0.2
3.0
0.3
3.0
3.5
10
1
mA
mA
mA
mA
mA
mA
kΩ
kΩ
µs
µs
°C
°C
Ground Pin Current (Note 3) Regulator disabled (only V
OUT
present)
Regulator selected, I
LOAD
=5mA
Regulator selected = 5V, I
LOAD
=500mA
Drive R
DS
High
Drive R
DS
Low
Drive High Delay
Drive Low Delay
Shutdown Temperature
Thermal Hysteresis
R
DS
to V
CC
, V
CC
> V
CCSEL
R
DS
to GND, V
CCDES
> V
CC
C
DRIVE
=1nF, V
CC
t
RISE
< 100ns
C
DRIVE
=1nF, V
CC
t
FALL
< 100ns
R
OH
R
OL
t
DH
t
DL
T
DISABLE
T
HYST
0.5
165
30
Note 1: Operating Characteristics are over Standard Operating Conditions unless otherwise specified.
Note 2: The hysteresis defines the maximum level of acceptable disturbance on V
CC
during switching. It is recommended that the
V
CC
source impedance be kept below 0.15Ω to ensure the switching disturbance remains below the hysteresis during select/
deselect transitions.
Note 3: Ground pin current consists of controller current (0.2mA) and regulator current when selected.
©
2004 California Micro Devices Corp. All rights reserved.
4
430 N. McCarthy Blvd., Milpitas, CA 95035-5112
●
Tel: 408.263.3214
●
Fax: 408.263.7846
●
www.calmicro.com
08/16/04
CMPWR280
Typical DC Characteristics
Unless stated otherwise, all DC characteristics were
measured at room temperature with a nominal V
CC
supply voltage of 5.0 volts and an output capacitance
of 10
µ
F.
V
CC
Line Regulation,
as shown in
Figure 1,
is mea-
sured while forcing the deselect threshold to an artifi-
cial low level for loads of 100mA, 500mA and 1.5A. At
the maximum rated load of 1.5A, a drop in line regula-
tion occurs when the V
CC
supply voltage drops below
3.8V. For light load conditions (100mA), regulation is
maintained as low as 3.2V.
Line Regulation
3.35
3.30
3.25
V
CC
Load Regulation (pulse condition)
performance
is shown up to and beyond the rated load. A change in
load from 10% to 100% of rated current (150mA to
1500mA) results in an output voltage change of about
20mV. This translates into an effective output imped-
ance of less than 15MΩ
.
3.36
3.34
3.32
VOUT [V]
3.30
3.28
3.26
3.24
0
500
1000
1500
100mA load
VOUT [V]
3.20
3.15
3.10
3.05
3.3
500mA load
1.5A load
Load Current [mA]
Figure 2. V
CC
Load Regulation
V
SBY
Load Regulation (pulse condition)
perfor-
mance is shown up to and beyond the rated load. A
change in load from 10% to 100% of rated (50mA to
500mA) results in an output voltage change of about
20mV. This translates into an effective output imped-
ance of less than 50MΩ.
3.36
3.34
3.6
3.9
4.2
4.5
4.8
VCC [V]
Figure 1. V
CC
Line Regulation
VOUT [V]
3.32
3.30
3.28
3.26
3.24
0
100
200
300
400
500
Load Current [mA]
Figure 3. V
SBY
Load Regulation
©
2004 California Micro Devices Corp. All rights reserved.
08/16/04
430 N. McCarthy Blvd., Milpitas, CA 95035-5112
●
Tel: 408.263.3214
●
Fax: 408.263.7846
●
www.calmicro.com
5
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