CMPWR025
Dual Input SmartOR
TM
Power Switch
Features
•
•
•
•
•
•
•
•
•
Implements logical "Input V
CC1
OR Input V
CC2
"
Integrated low impedance switches (0.2Ω TYP)
Operating supply range from 2.8V to 5.5V
Provides up to 600mA output current
Glitch-free output during supply switching
transitions
Low operating supply current of 20µA (TYP)
User-selectable hysteresis for supply selection
8-pin MSOP package
RoHS compliant (lead-free) finishing
Product Description
California Micro Devices’ SmartOR
™
CMPWR025 is a
dual input power switch that selects between two differ-
ent power inputs and delivers it to one output. The
device integrates two very low impedance power
switches and automatically implements an OR function
that selects the higher of the two inputs. Hysteresis is
built in (and is user selectable) to prevent switch chat-
ter.
The CMPWR025 is a much-improved solution over
simply ORing two diodes, due to the greatly reduced
losses of the CMPWR025 when compared to low for-
ward drop Schottky diodes.
The CMPWR025 is designed to operate above the 1W
(375mA at 3.3V) sleep mode rating stated in the PCI
Rev 2.2 spec. In fact the CMPWR025 current rating is
dependent upon the power dissipation resulting from
the voltage drop across the internal switch elements.
See the Typical DC Characteristics section in this data
sheet for details.
For IAPC (Instantly Available Personal Computer)
applications see CMD Application Note AP-211
“Instantly Available PCI Card Power Management”.
The CMPWR025 is housed in a 8-lead MSOP package
and is available with RoHS compliant lead-free finish-
ing.
Applications
•
•
•
•
•
•
PCI cards for Wake-On-LAN/Wake-On-Ring
Dual power systems
Systems with standby capabilities
Battery backup systems
See also Application Note AP-211
USB enabled mobile electronics such as MP3
Players, PDAs, Digital Cameras and Wireless
Handsets
Typical Application Circuit
Simplified Electrical Schematic
SW1
0.2Ω
CMPWR025
V
CC1
V
OUT
V
CC2
V
CC1
5V
V
CC1
V
OUT
+
C
OUT
+
+
-
V
CC2
5V
HYS
+
-
GND
-
V
OUT
SW2
0.2Ω
10
μ
F
V
CC2
HYS
GND
GND
© 2008 California Micro Devices Corp. All rights reserved.
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
●
Tel: 408.263.3214
Issue B – 06/23/08
●
Fax: 408.263.7846
●
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1
CMPWR025
PACKAGE / PINOUT DIAGRAM
Top View
V
CC1
V
CC1
V
CC2
V
CC2
1
8
HYS
V
OUT
V
OUT
GND
R025
2
3
4
7
6
5
8-pin MSOP
CMPWR025R
Note: This drawing is not to scale.
PIN DESCRIPTIONS
PIN(S)
1,2
NAME
V
CC1
DESCRIPTION
V
CC1
is the primary power source, which is given priority when present. If pin 8 (HYS) is uncon-
nected, then the hysteresis level is 75mV (typ.). Whenever the primary power source drops below
the secondary supply V
CC2
by more than 125mV, it will immediately become deselected. When the
primary power source is restored to within 50mV of the secondary supply, the primary power
source will once again be selected and provide all the output current. When V
CC1
is selected, it will
supply all the internal current requirements which are typically 20µA. When V
CC1
is not selected,
there will be no current loading on this input.
Pins 1 & 2 must be connected together externally.
V
CC2
is the secondary power source and is selected when the primary source has fallen below it by
more than 125mV (or 200mV if pin 8 is grounded). The secondary source will be deselected imme-
diately once the primary source is restored to within 50mV of V
CC2
. When V
CC2
is selected, it will
supply all the internal current requirements which are typically 20µA. When V
CC2
is not selected,
there will be no current loading on this input.
Pins 3 & 4 must be connected together externally.
Negative reference for all voltages.
Positive voltage output switched from V
CC1
or V
CC2
inputs. During normal operation the impedance
,
from V
OUT
to the selected supply is typically less than 0.28Ω which results in minimal voltage loss
from input to output. During the cold-start interval when both inputs are initially applied, the internal
circuitry provides a soft turn-on for the switches, which limits peak in-rush current.
Pins 6 & 7 must
be connected together externally.
HYS is the user-selectable hysteresis input. The hysteresis level is set to 150mV when pin 8 is
grounded. The default hysteresis level is set to 75mV by leaving pin 8 unconnected. Using 150mV
hysteresis is recommended, especially in environments with noisy power supplies, high power sup-
ply resistances or high load currents. If the hysteresis level is set to 150mV, the primary supply
V
CC1
must now fall 200mV below the secondary supply V
CC2
before it becomes deselected.
3,4
V
CC2
5
6,7
GND
V
OUT
8
HYS
Ordering Information
PART NUMBERING INFORMATION
Regulator
CMPWR025
Pins
8
Package
MSOP
Ordering Part Number
1
CMPWR025R
Part Marking
R025
Note 1: Parts are shipped in Tape & Reel form unless otherwise specified.
© 2008 California Micro Devices Corp. All rights reserved.
2
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
●
Tel: 408.263.3214
Issue B – 06/23/08
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Fax: 408.263.7846
●
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CMPWR025
Specifications
ABSOLUTE MAXIMUM RATINGS
PARAMETER
ESD Protection (HBM)
Pin Voltages
V
CC1
V
CC2
Maximum DC Output Current
Storage Temperature Range
Operating Temperature Range
Ambient
Junction
Power Dissipation
RATING
+2000
[GND - 0.5] to [+6.0]
[GND - 0.5] to [+6.0]
750
-65 to +150
-20 to +70
-20 to +125
0.3
UNITS
V
V
V
mA
°C
°C
°C
W
STANDARD OPERATING CONDITIONS
PARAMETER
V
CC1
and V
CC2
Input Voltage
Ambient Operating Temperature Range
I
LOAD
RATING
2.8 to 5.5
0 to +70
0 to 600
UNITS
V
°C
mA
© 2008 California Micro Devices Corp. All rights reserved.
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
●
Tel: 408.263.3214
Issue B – 06/23/08
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3
CMPWR025
Specifications (cont’d)
ELECTRICAL OPERATING CHARACTERISTICS
(SEE NOTE 1)
SYMBOL
V
CCDES1
V
CCDES2
V
CC1SEL
V
HYS1
V
HYS2
t
DL
t
DH
R
SW
V
SW
PARAMETER
V
CC1
Deselect
V
CC2
Deselect 2
V
CC1
Select Preference
Hysteresis
V
CC1SEL
-V
CC1DES
V
CC1SEL
-V
CC1DES
Switching Delay
Switch Resistance
HYS input (Pin 8) floating; Note 2
HYS input (Pin 8) grounded; Note 2
V
CC1,2
falltime < 100ns; Note 3
V
CC1,2
risetime < 100ns; Note 3
I
LOAD
= 0 to 600mA; V
CC1,2
= 2.8V; Note 4
I
LOAD
= 0 to 600mA; V
CC1,2
= 5.0V; Note 4
CONDITIONS
V
CC1
deselect level below V
CC2
; HYS input
(Pin 8) floating
V
CC1
deselect level below V
CC2
; HYS input
(Pin 8) grounded
MIN
50
90
10
40
80
TYP
125
200
50
75
150
200
200
0.28
0.21
28
56
168
21
42
125
0.4
0.3
40
80
240
30
60
180
100
100
MAX
200
300
100
100
200
UNITS
mV
mV
mV
mV
mV
ns
ns
Ω
Ω
mV
mV
mV
mV
mV
mV
µA
µA
µA
µA
50
µA
Voltage Drop Across Switch I
OUT
= 100mA; V
CC1,2
= 2.8V; Note 4
(V
CC1,2
- V
OUT
)
I
OUT
= 200mA; V
CC1,2
= 2.8V; Note 4
I
OUT
= 600mA; V
CC1,2
= 2.8V; Note 4
I
OUT
= 100mA; V
CC1,2
= 5.0V; Note 4
I
OUT
= 200mA; V
CC1,2
= 5.0V; Note 4
I
OUT
= 600mA; V
CC1,2
= 5.0V; Note 4
I
RCC1
I
RCC2
I
CC1
, I
CC2
I
GND
Reverse Leakage
Supply Current
Ground Pin Current
V
CC1
=0V; V
CC2
= 5.0V
V
CC1
=5.0V; V
CC2
= 0V
When selected (I
OUT
= 0)
When NOT selected
V
CC1
= V
CC2
= 5.0V; I
LOAD
= 0mA to 600mA
x
x
20
1
20
Note 1: Operating Characteristics are over Standard Operating Conditions unless otherwise specified.
Note 2: Hysteresis level defines the maximum level of acceptable noise on V
CC
during switching. Excessive parasitic inductance on
V
CC
board traces to the CMPWR025 may require an input capacitor to adequately filter the supply noise to below the hyster-
esis level. This will ensure that precise switching occurs between V
CC1
and V
CC2
supply inputs.
Note 3: This is the time, after the select/deselect threshold is reached, for the switches to react. Not tested, guaranteed by device
design and characterization.
Note 4: Guaranteed by design and characterization.
© 2008 California Micro Devices Corp. All rights reserved.
4
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
●
Tel: 408.263.3214
Issue B – 06/23/08
●
Fax: 408.263.7846
●
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CMPWR025
Selection Threshold Diagrams
Figure 1. Supply Threshold Diagram
(Hysteresis input pin floating, see Typical Application Circuit, pg. 1)
Figure 2. Supply Threshold Diagram
(Hysteresis input tied to GROUND, see Typical Application Circuit, pg. 1)
© 2008 California Micro Devices Corp. All rights reserved.
490 N. McCarthy Blvd., Milpitas, CA 95035-5112
●
Tel: 408.263.3214
Issue B – 06/23/08
●
Fax: 408.263.7846
●
www.cmd.com
5
