ETC CMPWR160SA/R

CMPWR160
CALIFORNIA MICRO DEVICES
USB Peripheral Power Management
Features
Applications
• 3.3V regulated output up to 500mA
• Bus-powered USB peripherals
• Quiescent current 35µA (typical)
• Self-powered USB peripherals
• Shutdown mode current 7µA (typical)
• Portable/battery-powered devices
• 30ms active LOW Power-On Reset (POR) pulse
• Critical power monitoring, hot-insertion devices
• Thermal overload protection
• Foldback current limiting protection
• Reverse-current protection
• 8 pin SOIC power package
The SmartORTM CMPWR160 combines a Low Dropout
Regulator (LDO) with a Power-On Reset (POR) pulse
generator, and is intended for Universal Serial Bus
(USB) peripherals. To meet the specification requirements of both USB 1.0 and USB 2.0, the CMPWR160
draws a very low quiescent current (35µA), and delivers
up to 500mA of load current at a fixed 3.3V output.
The POR pulse (active LOW) has a typical duration of
30ms after the output has exceeded and stabilized
above 2.9V. Thus a new POR pulse is developed each
time the regulator power is interrupted and restored,
which occurs often on USB buses when cables are
connected (or disconnected) by the user. It is not
necessary to have a VCC supply for POR to operate,
allowing the CMPWR160 to work in Wired-ORed power
systems.
When VCC is powered down, the device will automatically
enter reverse-current protection mode and maintain
isolation between VOUT and VCC. This is useful for applications that can use power from the USB port in addition to
internal batteries or an AC adapter supply (Wired-ORed
power systems). In the event of VCC collapsing below
VOUT, the device will automatically enter shutdown mode
and fully isolate the VCC power source from the output.
A ShutDown input (SD ) forces the regulator to be
powered down on demand. While in shutdown mode the
POR circuitry will remain active, making the device
suitable for systems which contain backup or alternative
power sources.
The CMPWR160 is available in an 8-pin SOIC thermally
enhanced package, ideal for applications where space
is tight.
Pin Diagram and Electrical Schematic
VCC
Top View
VCC
1
8
GND
SD
2
7
GND
POR
3
6
GND
VOUT
4
5
GND
SD
+
VREF
3.3V
SD
–
VOUT
3.3V/500mA
+
GND
CMPWR160
8 LEAD SOIC
POR
30ms
–
Pin Diagram
2.9V
Simplified Electrical Schematic
Standard Part Ordering Information
Package
Pin
8
Style
Tubes
Ordering Part Number
Tape & Reel
Part Marking
Power SOIC
CMPWR160SA/T
CMPWR160SA/R
CMPWR160SA
C1571000
©2001 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
215 Topaz Street, Milpitas, California 95035 5/22/2001
Tel: (408) 263-3214
Fax: (408) 263-7846
www.calmicro.com
1
CMPWR160
CALIFORNIA MICRO DEVICES
Absolute Maximum Ratings
Parameter
ESD Protection (HBM)
V CC /V OUT Voltage
Rating
Unit
2000
V
6.0, GND –0.5
V
SD Logic Input Voltage
V CC + 0.5, GND –0.5
V
POR Logic Output Voltage
V OUT + 0.5, GND –0.5
V
–40 to 150
0 to 70
0 to 125
˚C
Temperature: Storage
Operating Ambient
Operating Junction
Power Dissipation Note 1
Internally Limited
Operating Conditions
Parameter
VCC
Temperature (Ambient)
Load Current
CEXT
Range
Unit
4.2 to 5.5
V
0 to 70
˚C
0 to 500
mA
10 ± 10%
µF
Electrical Operating Characteristics
(over operating conditions unless specified otherwise)
Symbol
VOUT
Parameter
Regulator Output Voltage
ILIM
Regulator Current Limit
IS/C
Short-Circuit Current Limit
VR LOAD
Load Regulation
Conditions
0mA < ILOAD < 500mA
MIN
3.135
TYP
3.30
MAX
3.465
550
VCC = 5V, ILOAD = 5mA to 500mA
UNIT
V
mA
300
mA
75
mV
VR LINE
Line Regulation
VCC = 4.2V to 5.5V, ILOAD = 5mA
2
VDO
Regulator Dropout Voltage
MIN VCC – VOUT for ILOAD = 500mA
0.6
0.9
V
IQ
Quiescent Supply Current
Regulator Enabled (No Load)
35
50
µA
ISD
Shutdown Supply Current
Regulator Disabled
7
10
µA
1
10
µA
IRCC
VCC Pin Reverse Leakage
VOUT = 3.3V, VCC = 0V
VIH SD
Shutdown High Detect
VCC = 5V
VIL SD
Shutdown Low Detect
VCC = 5V
VPOR
POR Detect Threshold
4.2V < VCC < 5.5V
2.8
After POR Threshold Detected
Sinking to GND/Sourcing from VCC
mV
3.0
V
1.0
V
2.9
3.0
V
20
30
40
ms
0.2
0.5
2
kΩ
TPOR
POR Pulse Duration
RPOR
POR Output Impedance
TDISABLE
Shutdown Temperature
160
THYST
Thermal Hysteresis
20
˚C
˚C
Note 1: The SOIC package used is thermally enhanced through the use of a fused integral leadframe. The power rating is based on a printed
circuit board heat spreading capability equivalent to 2 square inches of copper connected to the GND pins. Typical multi-layer boards
using power plane construction will provide this heat spreading ability without the need for additional dedicated copper area. (Please
consult with factory for thermal evaluation assistance.)
©2001 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
2
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214
Fax: (408) 263-7846
www.calmicro.com
5/22/2001
CMPWR160
CALIFORNIA MICRO DEVICES
Interface Signals
VCC is the input power source for the Low Drop Out
Regulator, capable of delivering 3.3V/500mA output
current even when the input is as low as 4.2V.
Internal loading on this pin is typically 35µA when the
regulator is enabled, which reduces to only 7µA whenever the regulator is shutdown (SD taken Low). In the
event of VCC collapsing below VOUT, the loading at VCC will
immediately reduce to less than 0.1µA.
If the VCC pin is within a few inches of the main input
filter, a capacitor may not be necessary. Otherwise an
input filter capacitor in the range of 1µF to 10µF will
ensure adequate filtering.
SD is the regulator shutdown input logic signal which is
Active Low. This is a true CMOS input signal referenced
to VCC supply. When the pin is tied High (VCC ) the
regulator operates fully. When the pin is taken to GND,
the device enters shutdown mode and the regulator is
fully disabled. In this mode all critical POR circuitry
remains fully powered consuming less than 7µA (typical).
VOUT is the regulator output voltage used to power the
load. An output capacitor of 10µF is used to provide the
necessary phase compensation, thereby preventing
oscillation. The capacitor also helps to minimize the peak
output disturbance during line or load transients. Whenever VCC collapses below the output the device immedi-
ately enters reverse protection mode to prevent any
current flow back into the regulator pass transistor.
Under these conditions VOUT will also be used to provide
the necessary quiescent current for the internal reference and POR circuits. This ensures excellent start-up
characteristics for the regulator.
POR is the Power-On-Reset output pin (Active Low).
When VOUT rises above the POR threshold voltage
(typically 2.9V), the pin is forced to logic low (GND). The
pin remains logic low for 30ms then it is forced logic high
(3.3V). If VOUT falls below the POR threshold voltage
during this 30ms interval POR will remain logic low. If it
falls below the voltage threshold and then recovers the
30ms time will reset.
If VOUT falls below the POR threshold voltage POR is
immediately forced to logic low.
The power-on reset circuitry is designed to remain active
under all conditions and will produce a valid output even
when VCC is not present. A very low quiescent current
(7µA typical) ensures continuous operation of the POR
circuit.
GND is the negative reference for all voltages. This
current that flows in the ground connection is very low
(35µA typical with the regulator enabled and 7µA typical
with the regulator disabled).
Pin Functions
Symbol
Description
VCC
Positive supply input for regulator. When VCC falls below VOUT the regulator is disabled.
SD
Shutdown control input signal (Active Low) to disable internal voltage regulator and current supply
to less than 7µA.
POR
Power-On-Reset output signal is held Low until the output has been stable (>2.9V) for at least 30ms.
VOUT
Regulator voltage ouput (3.3V) capable of delivering 500mA when device is enabled (SD is High).
Whenever the output exceeds 2.9V (TYP) the POR pulse is triggered.
GND
Negative reference for all voltages
CMPWR160
VCC
+
VCC
5V +
CIN
SD
1µF
uP Reset
POR
VOUT
GND
VOUT
3.3V/500mA
+
COUT
10µF
–
GND
Typical Application Circuit
©2001 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
215 Topaz Street, Milpitas, California 95035 5/22/2001
Tel: (408) 263-3214
Fax: (408) 263-7846
www.calmicro.com
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CMPWR160
CALIFORNIA MICRO DEVICES
Typical DC Characteristics
Unless stated otherwise, all DC characteristics were
measured at room temperature with a nominal VCC
supply voltage of 5V and an output capacitance of 10µF.
Resistive load conditions were used.
3.35
5mA Load
3.30
500mA Load
VOUT (V)
3.25
Line Regulation Characteristics of the regulator are
shown in Figure 3. At maximum rated load conditions
(500mA), a 100mV drop in regulation occurs when the
line voltage has collapses below 3.8V. For light load
conditions (5mA), regulation is maintained for line
voltages as low as 3.3V.
3.20
3.15
3.10
3.05
3.0
3.5
4.0
VCC (V)
4.5
5.0
Figure 3. Line Regulation
3.40
3.35
VOUT (V)
Load Regulation performance is shown from zero to
maximum rated load in Figure 4. A 10% to 100%
change of rated load, results in an output voltage
change of less than 10mV. This translates into an
effective output impedance of approximately 0.02Ω.
3.30
3.25
3.20
0
200
400
600
Load Current (mA)
Figure 4. Load Regulation
100
Ground Current (µA)
Ground Current is shown across the entire range of
load conditions in Figure 5. The ground current increases by 40µA across the range of load conditions.
This increase is due to the current limiting protective
circuitry becoming active.
80
60
40
20
0
0
200
400
600
Load Current (mA)
Figure 5. Ground Current
©2001 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
4
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214
Fax: (408) 263-7846
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5/22/2001
CMPWR160
CALIFORNIA MICRO DEVICES
Typical DC Characteristics (continued)
60
50
Supply Current (µA)
VCC Operating Current (no load, SD high) is shown
across a range of VCC supply voltages with the regulator enabled in Figure 6. The graph shows that the
operating current is 35µA typical and changes by less
than 1µA across this range.
40
30
20
10
0
3.5
4.5
5.5
VCC (V)
Figure 6. VCC Operating Current (no load)
VCC Shutdown Current variation with the VCC supply
voltage is shown in Figure 7.
Supply Current (µA)
10
8
6
4
2
0
1.5
2.5
3.5
4.5
5.5
VCC (V)
Figure 7. VCC Shutdown Current
©2001 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
215 Topaz Street, Milpitas, California 95035 5/22/2001
Tel: (408) 263-3214
Fax: (408) 263-7846
www.calmicro.com
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CMPWR160
CALIFORNIA MICRO DEVICES
Typical Transient Characteristics
The transient characterization test setup is shown in
Figure 8. It was the setup used for the transient tests
unless specified otherwise.
A maximum rated load current of 6.6Ω (500mA @ 3.3V)
was used during characterization along with a nominal
VCC supply voltage of 5V DC, unless specified otherwise.
The load transient characterization was done by switching between 6.6 and 660Ω load resistors. This switched
the load between 500 and 5mA respectively.
For the VCC power-up and power-down characterizations
VCC supply was ramped between 0 and 5V. Both the rise
and fall times for the VCC power-up/down pulses were
controlled to be 15ms.
In the line transient characterizations the VCC supply
voltage was controlled to step between 4.5 to 5.5V.
For the POR response characterization VCC and SD were
tied to ground and the VOUT voltage was directly driven
between 2.7 and 3.1V. This was done by connecting a
function generator directly to the output of the device.
These voltage values were picked because it drove VOUT
directly across the typical POR threshold voltage of 2.9V.
VCC was tied to ground to show that the POR circuitry will
operate even when the VCC supply voltage is not present.
The oscilloscope traces show the full bandwidth response at the SD , POR , VCC and VOUT pins depending on
the characterization.
CMPWR160
POR
POR
VOUT
GND
VOUT
VCC
VCC
+ C1
10µF
C2
SD
0.1µF
C4
+ C3
0.1µF
(500mA)
6.6Ω
10µF
GND
GND
Figure 8. Transient Characterization Test Setup
VCC power-up Cold Start
Figure 9 shows the output response during an initial VCC
power up with SD tied to VCC. When VCC reaches a
particular threshold, the regulator turns on. The uncharged output capacitor causes maximum inrush
current to flow. At this point the device sees the output
as a short circuit and the device enters a protective
current limiting mode. The output capacitor quickly
charges and VOUT rises. Once this voltage rises to just
below VCC the inrush current stops flowing and the output
rises with the input. VOUT continues to rise with the input
until it reaches 3.3V.
Tek Run 25.0kS/s Sample
VCC
VOUT
(500mA Load)
1.00V
Ch2 1.00V M 2.00ms Ch2
280mV
Figure 9. VCC Power-up Cold Start
©2001 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
6
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214
Fax: (408) 263-7846
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5/22/2001
CMPWR160
CALIFORNIA MICRO DEVICES
Typical Transient Characteristics continued
VCC Power down
Tek Run 25.0kS/s Sample
Figure 10 shows the output response of the regulator
during a complete power down situation under full load
conditions with SD tied to VCC.
VCC
VOUT
(500mA Load)
Ch2 1.00V M 2.00ms Ch2
1.00V
3.50V
Figure 10. VCC Power Down
Shutdown Transient Response
Tek
The transient response of the output voltage to the SD
pin is shown in Figure 11. The graph shows that a
rising edge on the SD pin enables the regulator and a
falling edge disables the regulator.
2
25.0kS/s
3 Acqs
SD
The rise and fall time for the output voltages are 100µs
and 200µs respectively.
(500mA Load)
VOUT
1.00V
Ch2 5.00V
M 200µs Ch2
3.0V
Figure 11. Shutdown Transient Response
Tek Run 5.0kS/s
POR Response
The transient response of the active low POR pin to VOUT
is shown in Figure 12. When VOUT rises above the
POR threshold voltage (typically 2.9V), the pin is forced
to logic low (0V). The pin remains at logic low for 30ms
then it is forced to logic high (3.3V). If VOUT falls below the
POR threshold voltage during this 30ms interval POR
will remain logic low. If it falls below the voltage threshold
and then recovers the 30ms time will reset.
Sample
3.1V
VOUT
2
2.7V
When VOUT falls below the POR threshold voltage POR is
immediately forced to logic low.
VCC is tied to ground to show that the POR circuitry will
work without VCC present.
POR
1.00V
Ch2 200mV M 10.0ms Ch2
2.90V
Figure 12. POR Response
©2001 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
215 Topaz Street, Milpitas, California 95035 5/22/2001
Tel: (408) 263-3214
Fax: (408) 263-7846
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CMPWR160
CALIFORNIA MICRO DEVICES
Typical Transient Characteristics continued
Load Step response
Tek Run 250kS/s
Figure 13 shows the output voltage (Ch1) response of
the regulator during a step load change between 5mA
and 500mA (represented on Ch2). For the 5mA to
500mA transition an initial transient overshoot of 60mV
occurs and then the output settles to its final voltage
within 20µs. For the 500mA to 5mA transition there is
also an initial overshoot of 60mV however it takes
approximately 250µs to settle to its final voltage.
The overall DC voltage disturbance on the output is
approximately 25mV, which demonstrates the regulator
output impedance of 50mΩ.
Sample
500mA
Load
5mA
1
VOUT (offset = 3.3V)
VOUT offset = 3.3V
Ch1 50.0mV
2.00V
M 200µs Ch2
1.60V
Figure 13. Load Step Response
Line Step Response
250kS/s
Tek
Figure 14 shows the output response of the regulator to
a VCC line voltage transient between 4.5V and 5.5V
(1Vpp as shown on Ch2). The load condition during this
test is 5mA. The output response produces less than
10mV of disturbance on both edges indicating a line
rejection of better than 40dB at high frequencies.
2 Acqs
5.5V
VCC
2
4.5V
VOUT offset = 3.3V
(5mA Load)
VOUT(offset = 3.3V)
20.0mV Ch2 500mV M 200µs Ch2
5.00V
Figure 14. Line Step Response
Reset response time with overdrive
Figure 15 shows the time it takes for the POR signal to
reset when the output voltage is driven below the POR
trigger threshold by varying amounts. The amount the
voltage is driven below the POR trigger threshold is the
overdrive voltage.
Turn Off Delay (µs)
1000
100
10
1
0
50
100
150
200
250
300
Overdrive (mV)
Figure 15. Reset Response Time with Overdrive
©2001 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
8
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214
Fax: (408) 263-7846
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5/22/2001
CMPWR160
CALIFORNIA MICRO DEVICES
Typical Thermal Characteristics
Thermal dissipation of junction heat consists primarily
of two paths in series. The first path is the junction to
the case (θJC) thermal resistance which is defined by
the package style, and the second path is the case to
ambient (θCA) thermal resistance, which is dependent on
board layout.
The overall junction to ambient (θJA) thermal resistance is
equal to:
θJA = θJC + θCA
For a given package style and board layout, the operating junction temperature is a function of junction power
dissipation PJUNC, and the ambient temperature, resulting
in the following thermal equation:
TJUNC = TAMB + PJUNC (θJC ) + PJUNC (θCA )
= TAMB + PJUNC (θJA)
The CMPWR160SA is housed in a thermally enhanced
package where all the GND pins (5 through 8) are
integral to the leadframe (fused leadframe). When the
device is mounted on a double sided printed circuit
board with two square inches of copper allocated for
“heat spreading”, the resulting θJA is 50°C/W.
Based on a maximum power dissipation of
1.0W (2Vx500mA) with an ambient of 70°C the resulting
junction temperature will be:
TJUNC = TAMB + PJUNC (θJA )
= 70°C + 1.0W (50°C/W)
= 70°C + 50°C = 120°C
All thermal characteristics of the CMPWR160SA were
measured using a double sided board with two square
inches of copper area connected to the GND pins for
“heat spreading”.
Measurements showing performance up to junction
temperature of 125°C were performed under light load
conditions (5mA). This allows the ambient temperature to
be representative of the internal junction temperature.
Note: The use of multi-layer board construction with
power planes will further enhance the thermal performance of the package. In the event of no copper area
being dedicated for heat spreading, a multi-layer board
construction, using only the minimum size pad layout,
will typically provide the CMPWR160SA with an overall
θJA of 70°C/W which allows up to 780mW to be safely
dissipated.
Output Voltage vs. Temperature
3.35
3.33
VOUT (v)
Figure 16 shows the regulator VOUT performance up to
the maximum rated junction temperature. A 125°C
variation in junction temperature from –25°C causes an
output voltage variation of about 50mV, reflecting
a voltage temperature coefficient of approximately
±50ppm/°C.
3.31
3.29
3.27
3.25
–25
0
25
50
75
100
125
Temperature (˚C)
Figure 16. VOUT Temperature Variation (5mA)
©2001 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
215 Topaz Street, Milpitas, California 95035 5/22/2001
Tel: (408) 263-3214
Fax: (408) 263-7846
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CMPWR160
CALIFORNIA MICRO DEVICES
Typical Thermal Characteristics continued
Output Voltage (Rated) vs. Temperature
3.34
Figure 17 shows the regulator steady state performance when fully loaded (500mA) from –25°C up to the
rated maximum temperature of 70°C. The output
variation at maximum load is approximately 20mV
across the shown operating temperature. This translates to a temperature coefficient of approximately
±30ppm/°C.
3.32
VOUT (v)
3.30
3.28
3.26
3.24
–25
0
25
50
Temperature (˚C)
Figure 17. VOUT Temperature Variation (500mA)
POR Voltage Threshold Temperature Variation
The POR pulse duration does not vary with temperature.
3.00
POR Threshold (v)
Figure 18 shows the POR threshold voltage variation
from –25°C up to the maximum rated junction temperature. The overall 150°C change in junction temperature
causes less than a 5mV variation in the POR threshold
voltage. This translates to a temperature coefficient of
±6ppm/°C.
2.95
2.90
2.85
3.24
–25
0
25
50
75
100
125
100
125
Temperature (˚C)
Figure 18. POR Threshold
Temperature Variation
VCC Supply Current Temperature Variation
40
38
Current (µA)
Figure 19 shows the VCC supply current variation with
temperature from –25°C to the maximum rated junction
temperature with no load on the device. The supply
current changes less than 1µA over the entire 150°C
range shown in the plot.
36
34
32
30
–25
0
25
50
75
Temperature (˚C)
Figure 19. VCC Supply Current
vs. Temperature
©2001 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
10
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214
Fax: (408) 263-7846
www.calmicro.com
5/22/2001
CMPWR160
CALIFORNIA MICRO DEVICES
Applications
USB Bus-powered Peripheral Application
Universal Serial Bus (USB) peripherals can be powered
from the USB port. The cable carries signal on 2 lines,
a VBUS line which is nominally 5V at the source and a
GND wire. See Figure 1. For example, an external
modem (USB device or peripheral) draws its power
from the USB port of a personal computer (USB host),
and one definite advantage of bus-powered devices is
that they do not need extra power cords and plugs.
The USB specification (revisions 1.1 and 2.0) sets
various limitations on the power distribution. A buspowered device must draw no more than 500mA in
operating mode. A “Suspend” mode is entered when no
data is exchanged on the bus between the host and
the peripheral device. In this mode the current drawn
by the peripheral is reduced and may not exceed
500µA. The CMPWR160 addresses these requirements
by providing regulations up to 500mA, with overload
current limit, short-circuit current limit, and a very low
quiescent current.
Each peripheral is required to have one data line, D+ or
D–, connected to a 1.5KΩ pull-up resistor terminated to
a 3.3V reference. The resistor is either connected to
the D+ data line for selecting high-speed mode, or to
the D– data line for low-speed mode. The pull-up
resistor draws 200µA current on all USB devices. In
Suspend mode, there is only 300µA (500µA - 200µA)
left to power the controller and the regulator. Clearly,
the low quiescent current (35µA typical) of the
CMPWR160 is a definite advantage. The CMPWR160
3.3V output can be used as a reference voltage for the
pull-up resistor.
operating with an input VBUS voltage as low as 4.75V.
The CMPWR160 operates with input voltage down to
4.2V under full rated load of 500mA. It is suited for any
type of function even under transient conditions with
330mV drop on VBUS.
Power-On Reset Operation
The CMPWR160 asserts a reset signal (POR ) whenever the output voltage VOUT drops below the VPOR
threshold of 2.9V typical, keeping it asserted for 30ms
after VOUT has risen above the reset threshold. The
reset signal is active-low, and its high level voltage is
set by VOUT.
The device provides immunity to short-duration
negative-going pulse applied to VOUT. The data sheet
figure 15 on pg.8 shows typical transient duration
versus reset comparator overdrive (VPOR - VOUT), below
which the CMPWR160 will not generate a reset pulse.
In other words, the graph shows the maximum pulse
duration on a transient on VOUT that will not cause a
reset pulse. For example, a VOUT transient of 100mV
below the 2.9V threshold is detected only if it lasts for
4ms or more.
Dual Power Battery and USB Application
Some hand-held devices can be powered from two
independent supplies: either a battery or a computer
USB port 5V. These devices could also require a
regulated 3.3V. A dual CMPWR160 configuration, as
shown in Figure 2, provides uninterrupted power, so
that the device can remain fully “on” when plugged into
the USB port.
Figure 2. Dual Power USB/Battery
CMPWR160
VBUS
3.3V
CMPWR160
CMPWR160
USB_VBUS
USB_VBUS
VBUS
USB
HOST
D+
D–
GND
USB
CABLE
Rpu
1.5kΩ
VCC
VCC
3.3V
+ + CC
ININ
D+
D–
CONTROLLER
SD
SD
1µF
1µF
µP
µPReset
Reset
POR
POR
VOUT
VOUT
GND
GND
GND
VOUT
VOUT
3.3V/
3.3V/
500mA
500mA
GND
GND
1X
CMPWR160
CMPWR160
Figure 1. High-speed Device Cable
and Pull-up Resistor Connection
VCC
VCC
BATTERY
BATT + +
ININ
– – + + CC
1µF
1µF
USB peripherals are classified in two groups: low-power
and high-power bus-powered devices. Low-power
functions draw less that 100mA when operational and
must be capable of operating with input VBUS voltage as
low as 4.40V. High-power functions can draw up to
500mA when operational and must be capable of
SD
SD
µP
µPReset
Reset
POR
POR
VOUT
VOUT
GND
GND
+ + CC
OUT
OUT
10µF
10µF
GND
GND
Application Circuit
©2001 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
215 Topaz Street, Milpitas, California 95035 5/22/2001
Tel: (408) 263-3214
Fax: (408) 263-7846
www.calmicro.com
11
CMPWR160
CALIFORNIA MICRO DEVICES
Applications continued
Dual Power Battery
and USB Application (continued)
References
Possible usage for this configuration is in portable
equipment such as PDAs, wireless PDAs, cellular
phones, video camcorders, digital cameras, CD
players, MP3 players, and games.
1. California Micro Devices Application Note AP211,
“Instantly Available PCI Card Power
Management”.
2. Universal Serial Bus Specification Revision 1.1
and 2.0
The regulator is compatible with various battery
configurations using non-rechargeable alkaline “AA”
batteries of 1.5V each, or rechargeable Nickel-Metal
Hydride (NiMH) batteries of 1.2V per cell.
• 4 “AA” batteries (1.5V per cell): 4 X 1.5V = 6.0V
• 4 NiMH cell (1.2V per cell): 4 X 1.2V = 4.8V
• 3 “AA” batteries (1.5V per cell): 3 X 1.5V = 4.5V
• 3 NiMH cell (1.2V per cell): 3 X 1.2V = 3.6V
(200mA MAX rated)
©2001 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
12
215 Topaz Street, Milpitas, California 95035 Tel: (408) 263-3214
Fax: (408) 263-7846
www.calmicro.com
5/22/2001