MICREL MIC94305

MIC94305
500mA Switch
with Ripple Blocker™ Technology
General Description
Features
The MIC94305 is an integrated load switch that
incorporates Micrel’s Ripple Blocker active filter
technology. The MIC94305 provides high-frequency ripple
attenuation (switching noise rejection) for applications
where switching noise cannot be tolerated by sensitive
downstream circuits, such as RF applications. A lowvoltage logic enable pin disconnects the pass element and
puts the MIC94305 in a low current-shutdown state when
disabled.
The MIC94305 operates from an input voltage of 1.8V to
3.6V, allowing true load switching of low-voltage power
rails in any electronic device. The output voltage (VOUT) is
set at a fixed drop (typically 170mV) from the input voltage
(VOUT = VIN – 170mV). This maintains high efficiency
independent of given load conditions and currents.
The MIC94305 is packaged in a 6-ball 0.84mm x 1.32mm
CSP package, or 6-pin 1.6mm x 1.6mm Thin DFN
package, and has a junction operating temperature range
of −40°C to +125°C.
Data sheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
• 1.8V to 3.6V input voltage range
• Active noise rejection over a wide frequency band
− >60dB from 40kHz to 5MHz
• Rated to 500mA output current
• Current-limit and thermal-limit protected
• Ultra-small 0.84mm x 1.32mm, 6-ball CSP
• 1.6mm x 1.6mm, 6-pin Thin DFN
• Logic-controlled enable pin
• −40°C to +125°C junction temperature range
Applications
• Smart phones
• Tablet PC/notebooks and webcams
• Digital still and video cameras
• Videoconferencing
• Bar-code scanners
• Global positioning systems
• Automotive and industrial applications
_________________________________________________________________________________________________
Typical Application
PSRR COUT = 4.7µF
0
-10
PSRR (dB)
-20
500mA
-30
-40
300mA
-50
-60
-70
-80
VIN = 2.5V + 40mVpp
10
10
100
100
10mA
1K 10,000
10K 100,00
100K 1,000,0
1M 10,000,
10M
1,000
0
00
000
FREQUENCY (Hz)
Ripple Blocker is a trademark of Micrel, Inc
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • USA • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
September 2012
M9999-091312-A
Micrel, Inc.
MIC94305
Ordering Information
Part Number
Marking Code
Package
Lead Finish
MIC94305YCS*
W1
0.84mm × 1.32mm WLCSP
Pb-Free
1
2W
1.6mm × 1.6mm Thin DFN
Pb-Free
MIC94305YMT
Notes:
1.
Thin DFN is a GREEN RoHS-compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free.
∗
Contact Micrel Marketing for availability.
Pin Configuration
6-Ball 0.84mm × 1.32mm CSP (CS)
Ball View
6-Pin 1.6mm × 1.6mm Thin DFN (MT)
Top View
Note:
1.
Thin DFN ▲ = Pin 1 identifier.
Pin Description
Pin Number
(Thin DFN)
Ball Number
(CSP)
Pin Name
1, 2
A2, B2
VOUT
Power switch output.
3
C2
GND
Ground.
4
C1
EN
Enable input. A logic HIGH signal on this pin enables the part. Logic LOW
disables the output. Do not leave floating.
5, 6
A1, B1
VIN
Power switch input and chip supply.
EP
−
ePad
September 2012
Pin Name
Exposed heatsink pad. Connect to Ground for best thermal performance.
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Micrel, Inc.
MIC94305
Functional Block Diagram
MIC94305 Block Diagram
September 2012
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MIC94305
Absolute Maximum Ratings(1)
Operating Ratings(2)
Input Voltage (VIN) ........................................... −0.3V to +4V
Output Voltage (VOUT). .................................... −0.3V to +4V
Enable Voltage (VEN)..................−0.3V to VIN + 0.3V or +4V
Lead Temperature (soldering, 10s)............................ 260°C
Storage Temperature (TS)......................... −65°C to +150°C
ESD Rating(3) .................................................................. 3kV
Input Voltage (VIN)........................................ +1.8V to +3.6V
Enable Voltage (VEN).............................................. 0V to VIN
Junction Temperature (TJ) ........................ –40°C to +125°C
Junction Thermal Resistance
0.84mm x 1.32mm WLCSP (θJA) .....................160°C/W
1.6mm x 1.6mm Thin DFN (θJA) ........................92°C/W
Electrical Characteristics(4)
VIN = VEN = 3.6V; IOUT = 1mA; COUT = 4.7µF; TA = 25°C, bold values indicate –40°C ≤ TJ ≤ +125°C, unless noted.
Parameter
Condition
Min.
Typ.
1.8
Input Voltage
VIN − VOUT, −40°C ≤ TJ ≤ +85°C
170
f = 20kHz, IOUT = 500mA
45
f = 100kHz to 5MHz, IOUT = 500mA
55
Total Output Noise
f = 10Hz to 100kHz
98
Current Limit
VOUT = 0V
Turn-On Time
Voltage Drop
VIN Ripple Rejection (PSRR)
530
Max.
Units
3.6
V
250
mV
dB
µVRMS
725
1100
mA
EN controlled
90
150
µs
Load Regulation
100µA to 100mA
10
Ground Current
IOUT = 100µA
150
200
µA
Shutdown Current
VEN = 0V
0.2
5
µA
0.4
V
mV
Enable
Input Logic LOW
1.0
Input Logic HIGH
Input Current
V
0.01
1
µA
Notes:
1.
Exceeding the absolute maximum rating may damage the device.
2.
The device is not guaranteed to function outside its operating rating.
3.
Devices are ESD sensitive. Handling precautions are recommended. Human body model, 1.5kΩ in series with 100pF.
4.
Specification for packaged product only.
September 2012
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MIC94305
Typical Characteristics
PSRR COUT = 4.7µF
0
0
-10
-10
-10
-20
300mA
-50
-30
-40
-60
-60
-70
-70
VIN = 1.8V + 40mVpp
1K 10,000
10K 100,00
100K1,000,0
1M 10,000,
10M
100100 1, 000
0
00
000
10
10
100
100
300mA
-50
PSRR COUT = 10µF
PSRR COUT = 10µF
0
-10
-20
-20
-60
-20
500mA
-30
-40
300mA
-50
PSRR (dB)
300mA
PSRR (dB)
0
-10
-50
-60
-70
VIN = 1.8V + 40mVpp
10
10
VIN = 2.5V + 40mVpp
-40
10
10
100
100
10
10
1k 10,000
10k 100,00
100k1,000,0
1M 10,000,
10M
1,000
0
00
000
100
100
10mA
1k 10,000
10k 100,00
100k1,000,0
1M 10,000,
10M
1,000
0
00
000
FREQUENCY (Hz)
FREQUENCY (Hz)
FREQUENCY (Hz)
PSRR COUT = 22µF
PSRR COUT = 22µF
PSRR COUT = 22µF
0
0
-10
-10
-10
-20
-20
-20
500mA
-40
300mA
-50
-60
VIN = 1.8V + 40mVpp
10mA
-80
100
100
1K
1,000
10K 100,00
100K1,000,0
1M 10,000,
10M
10,000
0
00
000
FREQUENCY (Hz)
September 2012
PSRR (dB)
-30
-40
300mA
-50
-60
-40
300mA
-50
-60
-70
-70
10mA
VIN = 2.5V + 40mVpp
-80
10
10
500mA
-30
PSRR (dB)
-30
10
10
VIN = 3.6V + 40mVpp
-80
0
-70
300mA
-50
-70
10mA
-80
100 1,000
1k 10,000
10k 100,00
100k1,000,0
1M 10,000,
10M
100
0
00
000
500mA
-30
-60
-70
10mA
-80
10mA
1K 10,000
10K 100,00
100K 1,000,0
1M 10,000,
10M
1,000
0
00
000
FREQUENCY (Hz)
0
-40
100
100
FREQUENCY (Hz)
-10
500mA
VIN = 3.6V + 40mVpp
-80
10
10
1K 10,000
10K 100,00
100K 1,000,0
1M 10,000,
10M
1,000
0
00
000
PSRR COUT = 10µF
PSRR (dB)
-40
-70
10mA
VIN = 2.5V + 40mVpp
FREQUENCY (Hz)
-30
500mA
-30
-60
10mA
-80
1010
300mA
-50
PSRR (dB)
-40
PSRR (dB)
-30
-20
500mA
500mA
-80
PSRR (dB)
PSRR COUT = 4.7µF
0
-20
PSRR (dB)
PSRR COUT = 4.7µF
100
100
1K
1,000
10K 100,00
100K 1,000,0
1M 10,000,
10M
10,000
0
00
000
FREQUENCY (Hz)
5
-80
VIN = 3.6V + 40mVpp
10
10
100
100
1K
1,000
10mA
10K 100,00
100K1,000,0
1M 10,000,
10M
10,000
0
00
000
FREQUENCY (Hz)
M9999-091312-A
Micrel, Inc.
MIC94305
Typical Characteristics (Continued)
Output Voltage
vs. Output Current
Output Voltage
vs. Output Current
3.6
1.8
1.7
1.65
1.6
1.55
1.5
VIN = 1.8V
1.45
220
3.55
VOLTAGE DROP (mV)
OUTPUT VOLTAGE (V)
3.5
3.45
3.4
3.35
CIN = COUT = 4.7µF
1.4
50 100 150 200 250 300 350 400 450 500
160
140
120
100
80
60
40
CIN = COUT = 4.7µF
20
VIN = 2V
0
0
OUTPUT CURRENT (mA)
180
CIN = COUT = 4.7µF
3.3
0
200
V IN = 3.6V
0
50 100 150 200 250 300 350 400 450 500
50 100 150 200 250 300 350 400 450 500
OUTPUT CURRENT (mA)
Voltage Drop
vs. Input Voltage
OUTPUT CURRENT (mA)
Ground Current
vs. Input Voltage
Ground Current
vs. Output Current
250
180
160
240
GROUND CURRENT (µA)
CIN = COUT = 4.7µF
230
400mA
220
500mA
210
200
300mA
190
180
170
100mA
140
120
100
80
60
40
V IN = 2.8V
20
0
1.8
2
2.2
2.4
2.6
2.8
3
3.2
3.4
INPUT VOLTAGE (V)
160
500mA
300mA
150
140
100mA
130
10mA
120
0
3.6
CIN = COUT = 4.7µF
170
CIN = COUT = 4.7µF
50mA
160
GROUND CURRENT (µA)
OUTPUT VOLTAGE (V)
260
240
1.75
VOLTAGE DROP (mV)
Voltage Drop
vs. Output Current
50 100 150 200 250 300 350 400 450 500
OUTPUT CURRENT (mA)
1.8
2
2.2
2.4
2.6
2.8
3
3.2
3.4
3.6
INPUT VOLTAGE (V)
MIC94305YMT
Output Noise Spectral Density
100
NOISE µV/√Hz
10
1
0.1
0.01
VIN = VEN1 = 3V
COUT = 4.7µF
0.001
1010
100 1,000
1K 10,000
10K 100,00
100K1,000,0
1M 10,000,
10M
100
0
00
000
FREQUENCY (Hz)
September 2012
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MIC94305
Functional Characteristics
September 2012
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Micrel, Inc.
MIC94305
Application Information
Enable/Shutdown
The MIC94305 comes with an active-high enable pin
that allows the Ripple Blocker to be disabled. Forcing the
enable pin low disables the MIC94305 and sends it into
a “zero” off mode current state. In this state, current
consumed by the MIC94305 goes to nearly zero. Forcing
the enable pin high enables the output voltage. The
active-high enable pin uses CMOS technology and
cannot be left floating; a floating enable pin may cause
an indeterminate state on the output.
The MIC94305 uses Ripple Blocker technology to
integrate a load switch with a high-performance active
filter. The MIC94305 includes a low-voltage logic enable
pin, and is fully protected from damage caused by fault
conditions, offering linear current limiting and thermal
shutdown.
Input Capacitor
The MIC94305 is a high-performance, high-bandwidth
device. An input capacitor of 4.7µF from the input to
ground is required to provide stability. Low-ESR ceramic
capacitors provide optimal performance using a
minimum of space. Additional high-frequency capacitors,
such as small-valued NPO dielectric-type capacitors,
help filter out high-frequency noise and are good
practice in any RF-based circuit. X5R or X7R dielectrics
are recommended for the input capacitor. Y5V dielectrics
lose most of their capacitance over temperature and are
not recommended.
Thermal Considerations
The MIC94305 is designed to provide 500mA of
continuous current in a very small package. Maximum
ambient operating temperature can be calculated based
on the output current and the voltage drop across the
part, which is fixed at 170mV typical, 250mV worst case.
For example, if the input voltage is 2.75V, the output
voltage is 2.5V, and the output current is 500mA. The
actual power dissipation of the Ripple Blocker™ can be
determined using the equation:
Output Capacitor
The MIC94305 requires an output capacitor of 4.7µF or
greater to maintain stability. For optimal ripple rejection
performance, a 4.7µF capacitor is recommended. The
design is optimized for use with low-ESR ceramic-chip
capacitors. High-ESR capacitors are not recommended
because they may cause high-frequency oscillation. The
output capacitor can be increased, but performance has
been optimized for a 4.7µF ceramic output capacitor and
does not improve significantly with larger capacitance.
X7R/X5R dielectric-type ceramic capacitors are
because
of
their
temperature
recommended
performance. X7R-type capacitors change capacitance
by 15% over their operating temperature range and are
the most stable type of ceramic capacitors. Z5U and
Y5V dielectric capacitors change value by as much as
50% and 60%, respectively, over their operating
temperature ranges. If you use a ceramic-chip capacitor
with a Y5V dielectric, the value must be much higher
than an X7R ceramic capacitor to ensure the same
minimum capacitance over the equivalent operating
temperature range.
PD = (VIN − VOUT) IOUT + VIN IGND
Because this device is CMOS and the ground current is
typically <100µA over the load range, the power
dissipation contributed by the ground current is <1% and
can be ignored for this calculation:
PD = (2.75V − 2.5V) × 500mA
PD = 0.125W
To determine the package’s maximum ambient operating
temperature, use the junction-to-ambient thermal
resistance of the device and the following basic equation:
⎛ TJ(MAX) − TA
PD(MAX) = ⎜⎜
θ JA
⎝
TJ(MAX) = 125°C, the maximum junction temperature of the
die; θJA thermal resistance = 160°C/W for the YCS
package, and 92°C/W for the YMT package.
No Load Stability
The MIC94305 will remain stable with no load. This is
especially important in CMOS RAM keep-alive
applications.
September 2012
⎞
⎟
⎟
⎠
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Micrel, Inc.
MIC94305
Substituting PD for PD(MAX) and solving for the ambient
operating temperature gives the maximum operating
conditions for the regulator circuit.
For proper operation, do not exceed the maximum
power dissipation.
For example, when operating the MIC94305YMT at a
2.75V input voltage and 500mA load with a minimum
footprint layout, the maximum ambient operating
temperature TA can be determined as follows:
0.125W = (125°C − TA)/(92 °C/W)
TA = 113.5°C
It follows from this equation that the maximum ambient
operating temperature of 113.5°C is allowed in a 1.6mm
x 1.6mm DFN package. For a full discussion of heat
sinking and thermal effects on voltage regulators, refer
to the “Regulator Thermals” section of Micrel’s Designing
with Low-Dropout Voltage Regulators handbook. This
information can be found on Micrel's website at:
http://www.micrel.com/_PDF/other/LDOBk_ds.pdf
For more information about Micrel’s Ripple Blocker
products, go to:
http://www.micrel.com/rippleblocker/
http://www.micrel.com/page.do?page=/productinfo/products/mic94300.jsp
http://www.micrel.com/page.do?page=/productinfo/products/mic94310.jsp
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MIC94305
Typical Application Schematic
Bill of Materials
Item
Part Number
CIN, COUT
C1005X5R1A475K
U1
MIC94305YCS
Manufacturer
(1)
TDK
Micrel, Inc.(2)
Description
Qty.
Capacitor, 4.7µF Ceramic, 10V, X7R, Size 0603
2
500mA Switch with Ripple Blocker Technology
1
Notes:
1. TDK: www.tdk.com.
2. Micrel, Inc.: www.micrel.com.
September 2012
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MIC94305
Package Information(1)
6-Ball 0.84mm × 1.32mm WL-CSP (CS)
Note:
1.
Package information is correct as of the publication date. For updates and most current information, go to www.micrel.com.
September 2012
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MIC94305
Package Information(1) (Continued)
6-Pin 1.6mm × 1.6mm Thin DFN (MT)
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MIC94305
MICREL, INC. 2180 FORTUNE DRIVE SAN JOSE, CA 95131 USA
TEL +1 (408) 944-0800 FAX +1 (408) 474-1000 WEB http://www.micrel.com
Micrel makes no representations or warranties with respect to the accuracy or completeness of the information furnished in this data sheet. This
information is not intended as a warranty and Micrel does not assume responsibility for its use. Micrel reserves the right to change circuitry,
specifications and descriptions at any time without notice. No license, whether express, implied, arising by estoppel or otherwise, to any intellectual
property rights is granted by this document. Except as provided in Micrel’s terms and conditions of sale for such products, Micrel assumes no liability
whatsoever, and Micrel disclaims any express or implied warranty relating to the sale and/or use of Micrel products including liability or warranties
relating to fitness for a particular purpose, merchantability, or infringement of any patent, copyright or other intellectual property right.
Micrel Products are not designed or authorized for use as components in life support appliances, devices or systems where malfunction of a product
can reasonably be expected to result in personal injury. Life support devices or systems are devices or systems that (a) are intended for surgical implant
into the body or (b) support or sustain life, and whose failure to perform can be reasonably expected to result in a significant injury to the user. A
Purchaser’s use or sale of Micrel Products for use in life support appliances, devices or systems is a Purchaser’s own risk and Purchaser agrees to fully
indemnify Micrel for any damages resulting from such use or sale.
© 2012 Micrel, Incorporated.
September 2012
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