MIC94310
200mA LDO with
Ripple Blocker™ Technology
General Description
The MIC94310 Ripple Bloc ker™ is a monolithic integr ated
circuit that provides low-frequency ripple attenuation
(switching noise rejection) to a regulated output voltage.
This is important f or applic a tions wher e a DC/DC s witc hin g
converter is re quired t o lo wer or raise a batt er y voltag e but
where switching noise cannot be tolerated by sensitive
downstream circuits such as in RF applications. The
MIC94310 maintains high power supply ripple rejection
(PSRR) with input voltages operating near the output
voltage level to improve overall system efficiency. A low-
voltage logic enable pin facilitates ON/OFF control at
typical GPIO voltage levels.
The MIC94310 operates from an input voltage of 1.8V to
3.6V.
Packaged in a 0.88mm × 0.88mm 4-ball WLCSP, a 4-pin
1.2mm × 1.6mm Thin DFN, or a 5-pin SOT-23, the
MIC94310 has a junction operating temperature range of
–40°C to +125°C.
Datasheets and support documentation are available on
Micrel’s web site at: www.micrel.com.
Features
• 1.8V to 3.6V input voltage range
• Active noise rejection over a wide frequency band
− >50dB from 10Hz to 10MHz at 200mA load
• Rated to 200mA output current
• Fixed output voltages
• Current-limit and thermal-limit protected
• Ultra-small 0.88mm × 0.88mm 4-ball WLCSP
• 1.2mm × 1.6mm 4-pin Thin DFN
• 5-pin SOT-23
• Logic-controlled enable pin
− −40°C to +125°C junction temperature range
Applications
• Smartphones/Smart books
• Tablet PC/notebooks and webcams
• Digital still and video cameras
• Global positioning systems
• Mobile computing
• Automotive and industrial applications
Typical Appli cation
PSRR C
OUT
= 1µF
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
FREQUENCY (Hz)
PSRR ( d B)
IOUT = 200mA
IOUT = 100mA
IOUT = 10mA
VIN = 2. 5V + 40m V pp
VOUT = 1.8V
10
100
1K
10K
100K
1M
10M
Ripple Blocker is a trademark of Micrel, Inc.
Micrel Inc. • 2180 Fortune Drive • San Jose, CA 95131 • US A • tel +1 (408) 944-0800 • fax + 1 (408) 474-1000 • http://www.micrel.com
September 11, 2014 Revision 2.1
Micrel, Inc.
MIC94310
Ordering Information
Part Number Marking Code Output Voltage Package
(1, 2)
Lead Finish
MIC94310-4YCS 1Z 1.2V 0.88mm × 0.88mm WLCSP Pb-Free
MIC94310-FYCS 2Z 1.5V 0.88mm × 0.88mm WLCSP Pb-Free
MIC94310-GYCS Z9 1.8V 0.88mm × 0.88mm WLCSP Pb-Free
MIC94310-DYCS Z8 1.85V 0.88mm × 0.88mm WLCSP Pb-Free
MIC94310-JYCS Z7 2.5V 0.88mm × 0.88mm WLCSP Pb-Free
MIC94310-LYCS 3Z 2.7V 0.88mm × 0.88mm WLCSP Pb-Free
MIC94310-MYCS Z6 2.8V 0.88mm × 0.88mm WLCSP Pb-Free
MIC94310-NYCS Z5 2.85V 0.88mm × 0.88mm WLCSP Pb-Free
MIC94310-PYCS Z4 3.0V 0.88mm × 0.88mm WLCSP Pb-Free
MIC94310-SYCS Z3 3.3V 0.88mm × 0.88mm WLCSP Pb-Free
MIC94310-4YMT 31T 1.2V 1.2mm × 1.6mm Thin DFN Pb-Free
MIC94310-FYMT 32T 1.5V 1.2mm × 1.6mm Thin DFN Pb-Free
MIC94310-GYMT 31G 1.8V 1.2mm × 1.6mm Thin DFN Pb-Free
MIC94310-DYMT 31D 1.85V 1.2mm × 1.6mm Thin DFN Pb-Free
MIC94310-JYMT 31J 2.5V 1.2mm × 1.6mm Thin DFN Pb-Free
MIC94310-LYMT 31L 2.7V 1.2mm × 1.6mm Thin DFN Pb-Free
MIC94310-MYMT 31M 2.8V 1.2mm × 1.6mm Thin DFN Pb-Free
MIC94310-NYMT 31N 2.85V 1.2mm × 1.6mm Thin DFN Pb-Free
MIC94310-PYMT 31P 3.0V 1.2mm × 1.6mm Thin DFN Pb-Free
MIC94310-SYMT 31S 3.3V 1.2mm × 1.6mm Thin DFN Pb-Free
MIC94310-4YM5 V31 1.2V 5-Pin SOT-23 Pb-Free
MIC94310-GYM5 W31 1.8V 5-Pin SOT-23 Pb-Free
MIC94310-MYM5 Z31 2.8V 5-Pin SOT-23 Pb-Free
MIC94310-SYM5 X31 3.3V 5-Pin SOT-23 Pb-Free
Note:
1. Thin DF N ▲ = Pin 1 identifier.
2. Thin DFN is a GREEN RoHS-compliant pack age. Lead finish is NiPdAu. Mold compound is Halogen Free.
September 11, 2014 2 Revision 2.1
Micrel, Inc.
MIC94310
Pin Configuration
0.88mm × 0.88mm 4-Ball CSP (CS)
Top View
1.2mm × 1.6mm 4-Pin TDFN (MT)
Top View
5-Pin SOT-23 (M5)
Top View
Pin Description
Pin Number
(TDFN) Pin Number
(SOT-23) Ball Number
(WLCSP) Pin Name Pin Function
1 5 A2 VOUT Power switch output.
2 2 B2 GND Ground.
3 3 B1 EN Enable Input. A logic HIGH signal on this pin enables the part.
Logic LOW disables the part. Do not leave floating.
4 1 A1 VIN Power switch input and chip supply.
– 4 – NC No Connect. Not internall y connected.
EP – – ePad Exposed Heatsink Pad. Connect to ground for best thermal
performance.
September 11, 2014 3 Revision 2.1
Micrel, Inc.
MIC94310
Functional Diagram
September 11, 2014 4 Revision 2.1
Micrel, Inc.
MIC94310
Absolute Maximum Ratings(3)
Input Voltage (VIN) ........................................... –0.3 to +4.0V
Output Voltage (VOUT) ................. –0.3 to VIN+0.3V or +4.0V
Enable Voltage (VEN) ................... –0.3 to VIN+0.3V or +4.0V
Lead Temperature (soldering, 10s) ............................ 260°C
Storage Temperature (Ts) ......................... –65°C to +150°C
ESD Rating(5) .................................................................. 3kV
Operating Ratings(4)
Supply Voltage (VIN) ..................................... +1.8V to +3.6V
Enable Voltage (VEN) .............................................. 0V to VIN
Junction Temperature (TJ) ........................ –40°C to +125°C
Junction Thermal Resistance
TDFN (θJA) ....................................................... 173°C/W
WLCSP (θJA) .................................................... 250°C/W
SOT-23 (θJA) .................................................... 120°C/W
Electrical Characteristics(6)
VIN = VEN = VOUT + 500mV (VIN = VEN = 3.6V for VOUT ≥ 3.1V); IOUT = 1mA; COUT = 1µF (YCS, YMT), COUT = 10µF (YM5); TA = 25°C,
bold values indi cat e –40°C≤ TJ ≤ +125°C, unless noted.
Parameter Condition Min. Typ. Max. Units
Input Voltage 1.8 3.6 V
Output Voltage Accuracy Variation from nominal VOUT
–3
±1
+3
%
Dropout Voltage VIN to VOUT dropout at 100mA output current 20 50 mV
VIN to VOUT dropout at 200mA output current 40 100 mV
Load Regulation 1mA to 100mA 4 mV
Line Regulation VIN = VOUT + 500mV to 3.6V 0.01 0.5 %
Ground Current No load to full load 170 250 µA
Shutdown Current VEN = 0V 0.2 5 µA
VIN Ripple Rejection
f = 100Hz, IOUT = 100mA 85 dB
f = 100kHz, IOUT = 100mA 68 dB
f = 1MHz, IOUT = 100mA 57 dB
f = 10MHz, IOUT = 100mA 50 dB
Current Limit VOUT = 0V 250 400 700 mA
Total Output Noise 10Hz to 100kHz 83 μVRMS
Turn-on Time 70 μs
Enable
Input Logic Level 0.4 V
Input Logic High 1.0 V
Input Current 0.01 1 µA
Notes:
3. Exceeding the absolute maximum ratings may damage the device.
4. The device is not guaranteed to functi on outside its operat i ng ratings.
5. Devices are ESD sensitive. Handling precauti ons are recomm ended. Human body model, 1.5kΩ in series with 100pF.
6. Specific at i on for pack aged product only.
September 11, 2014 5 Revision 2.1
Micrel, Inc.
MIC94310
Typical Characteris tics
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
PSRR (dB)
FREQUENCY (Hz)
PSRR C
OUT
= 0.47µF
I
OUT
= 10mA
I
OUT
= 200mA
I
OUT
= 100mA
V
IN
= 2.5V + 40mVpp
V
OUT
= 1.8V
10
100
1K
10K
100K
1M
10M
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
PSRR (dB)
FREQUENCY (Hz)
PSRR C
OUT
= 0.47µF
V
IN
= 3.6V
V
IN
= 2.5VV
IN
= 2.0V
V
IN
= V
IN(NOM)
+ 40mVpp
LOAD = 100mA
V
OUT
= 1.8V
10
100
1K
10K
100K
1M
10M
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
PSRR (dB)
FREQUENCY (Hz)
PSRR C
OUT
= 1µF
I
OUT
= 200mA
I
OUT
= 100mA
I
OUT
= 10mA
V
IN
= 2.5V + 40mVpp
V
OUT
= 1.8V
10
100
1K
10K
100K
1M
10M
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
PSRR (dB)
FREQUENCY (Hz)
PSRR C
OUT
= 1µF
V
IN
= 3.6V
V
IN
= 2.5V
V
IN
= 2.0V
V
IN
= V
IN(NOM)
+ 40mVpp
LOAD = 100mA
V
OUT
= 1.8V
10
100
1K
10K
100K
1M
10M
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
PSRR (dB)
FREQUENCY (Hz)
PSRR C
OUT
= 2.2µF
I
OUT
= 200mA
I
OUT
= 100mA
I
OUT
= 10mA
V
IN
= 2.5V + 40mVpp
V
OUT
= 1.8V
10
100
1K
10K
100K
1M
10M
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
PSRR (dB)
FREQUENCY (Hz)
PSRR C
OUT
= 2.2µF
V
IN
= 3.6V
V
IN
= 2.5V
V
IN
= 2.0V
V
IN
= V
IN(NOM)
+ 40mVpp
LOAD = 100mA
V
OUT
= 1.8V
10
100
1K
10K
100K
1M
10M
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
PSRR (dB)
FREQUENCY (Hz)
PSRR C
OUT
= 4.7µF
I
OUT
= 200mA
I
OUT
= 100mA
I
OUT
= 10mA V
IN
= 2.5V + 40mVpp
V
OUT
= 1.8V
10
100
1K
10K
100K
1M
10M
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
PSRR (dB)
FREQUENCY (Hz)
PSRR C
OUT
= 4.7µF
V
IN
= 3.6V
V
IN
= 2.5V
V
IN
= 2.0V
V
IN
= V
IN(NOM)
+ 40mVpp
LOAD = 100mA
V
OUT
= 1.8V
10
100
1K
10K
100K
1M
10M
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
PSRR (dB)
FREQUENCY (Hz)
PSRR C
OUT
= 10µF
I
OUT
= 200mA
I
OUT
= 100mA
I
OUT
= 10mA
V
IN
= 2.5V + 40mVpp
V
OUT
= 1.8V
10
100
1K
10K
100K
1M
10M
September 11, 2014 6 Revision 2.1
Micrel, Inc.
MIC94310
Typical Characteristics (Continued)
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
PSRR (dB)
FREQUENCY (Hz)
PSRR C
OUT
= 10µF
V
IN
= 3.6V
V
IN
= 2.5V V
IN
= 2.0V
V
IN
= V
IN(NOM)
+ 40mVpp
LOAD = 100mA
V
OUT
= 1.8V
10
100
1K
10K
100K
1M
10M
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
PSRR (dB)
FREQUENCY (Hz)
PSRR (Varying C
OUT
)
C
OUT
= 2.2µF
C
OUT
= 1µF
C
OUT
= 0.47µF
V
IN
= 2.5V + 40mVpp
LOAD = 100mA
V
OUT
= 1.8V
10
100
1K
10K
100K
1M
10M
Dropout Voltage
vs. Output C urrent
0
5
10
15
20
25
30
35
025 50 75 100 125 150 175 200
O UT PUT CURRE NT (mA)
DROPOUT VOLTAGE (mV)
Output Voltage
vs. Output C urrent
1.700
1.725
1.750
1.775
1.800
1.825
1.850
1.875
1.900
020 40 60 80 100 120 140 160 180 200
O UT PUT CURRE NT (mA)
O UTPUT VOLTAG E ( V)
V
IN
= 3. 6V
C
IN
= C
OUT
= 1 µF
Output Voltage
vs. Input Voltage
1.60
1.65
1.70
1.75
1.80
1.85
1.90
1.95
2.00
22.2 2.4 2.6 2.8 33.2 3.4 3.6
I NPUT VO L TAGE (V)
O UTPUT VOLTAG E ( V)
I
OUT
= 200m A
Ground Current
vs. O utput Current
150
155
160
165
170
175
020 40 60 80 100 120 140 160 180 200
O UT PUT CURRE NT (mA)
GROUND CURRENT (μA)
V
IN
= 2. 8V
C
IN
= C
OUT
= 1 µF
Ground Current
vs. Input V oltage
120
130
140
150
160
170
180
190
22.2 2.4 2.6 2.8 33.2 3.4 3.6
I NPUT VO L TAGE (V)
GROUND CURRENT (μA)
I
OUT
= 100m A
I
OUT
= 200m A
C
IN
= C
OUT
= 1 µF
PSRR (Varying COUT)
-120
-100
-80
-60
-40
-20
0
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
FREQUENCY (Hz)
PSRR ( d B)
C
OUT
= 2. 2µF
C
OUT
= 10µF
C
OUT
= 4. 7µF
V
IN
= 2. 5V + 40m Vpp
LOA D = 100m A
V
OUT
= 1. 8V
10
100
1K
10K
100K
1M
10M
Output Noise Spectral Density
0.01
0.10
1.00
10.00
1.E+01 1.E+02 1.E+03 1.E+04 1.E+05 1.E+06
FREQUENCY (Hz)
Noise µV/√Hz
V
IN
= V
EN
= 3. 1V
C
IN
= C
OUT
= 1 µF
V
OUT
= 1. 8V
NOISE (10Hz to 100kHz)
= 82. 55µV
RMS
10
100
1k
10k
100k
1M
September 11, 2014 7 Revision 2.1
Micrel, Inc.
MIC94310
Functional Characteristics
September 11, 2014 8 Revision 2.1
Micrel, Inc.
MIC94310
Application Information
The MIC943 10 is a ver y-high P SRR, fix ed-outp ut, 200mA
LDO utilizing Ripple Blocker technology. The MIC94310
is fully protected from damage due to fault conditions,
offering linear current limiting and thermal shutdown.
Input Capacitor
The MIC94310 is a high-performance, high-bandwidth
device. An input capacitor of 0.47µF is required from the
input to ground to provide stability. Low-ESR ceramic
capacitors provide optimal performance at 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
therefore, not recommended.
Output Capacitance
In order to maintain stability, the MIC94310 requires an
output capacitor of 0.47µF or greater for the Thin DFN
and WLCSP packages and 10µF or greater for the SOT-
23 package. For optimal ripple rejection performance a
1µF capacitor is recommended for the CSP and Thin
DFN packages, while a 10µF capacitor is recommended
for the SOT -23 package. The design is opt imized 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 1µF ceramic output capacitor and does not im prove
significan tly with larger cap ac itance .
X7R/X5R dielectric type ceramic capacitors are
recommended because of their temperature
performance. X7R type capacitors change capacitance
by 15% over their operating temperature range and are
the m ost stable t ype of cer amic capacitors. Z 5U and Y5 V
dielectric capacitors change their value by as much as
50% and 60%, respectively, over their operating
temperature rang es . T o us e a c er amic chip c a pac it or w ith
the 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.
No Load Sta bility
The MIC94310 will remain stable and in regulation with
no load. This is especially important in CMOS RAM keep-
alive applications.
Enable/Shutdown
Forcing the enable (EN) pin low disables the MIC94310
and sends it into a “zero” off mode current state. In this
state, curr ent consum ed by the MIC9 4310 goes near ly to
zero. Forcing EN high enables the output voltage. The
EN pin uses CMOS tec hn ol og y and cannot be left f loati ng
as it could cause an indeterminate state on the output.
Thermal Considerations
The MIC94310 is designed to provide 200mA 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. For example if the input voltage is 2.5V, the output
voltage is 1.8V, and the output current = 200mA. The
actual power dissipation of the Ripple Blocker™ can be
determined using Equat ion 1:
PD = (VIN – VOUT1) IOUT + VIN IGND Eq. 1
Because this device is CMOS and the ground current is
typically <170µA over the load range, the power
dissipation contributed by the ground current is <1% and
can be ignored for this calculation.
PD = (2.5V – 1.8V) × 200mA
PD = 0.14W
To determine the maximum ambient operating
temperature of the package, use the junction-to-ambient
thermal resistance of the device and the Equation 2:
−
=JA
AJ(max)
D(MAX) θ
TT
P
Eq. 2
TJ(MAX) = 125ºC, the m aximum junction tem peratur e of the
die, θJA thermal resistance = 173°C/W for the Thin DFN
package.
Substituting PD for PD(MAX) and solving for the ambient
operating temperature will give the maximum operating
conditions for the regulator circuit.
September 11, 2014 9 Revision 2.1
Micrel, Inc.
MIC94310
For proper operation, the maximum power dissipation
must not be exceeded.
For exam ple, when oper ating the MIC943 10-GYMT at an
input voltage of 2.5V and 200mA load with a minimum
footprint layout, the maximum ambient operating
temperature (TA) can be determined as follows:
0.14W = (125ºC – TA)/(173ºC/W)
TA = 101ºC
Therefore, the maximum ambient operating temperature
allowed in a 1.2mm × 1.6mm Thin DFN package is
101ºC. For a full discussion of heat sinking and thermal
effects on voltage regulators, refer to the “Regulator
Thermals” s ect ion of Mic rel’ s Des igning 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, please visit:
http://www.micrel.com/index.php/en/products/power-
management-ics/ldos/linear-power-filters.html
http://www.micrel.com/index.php/en/products/power-
management-ics/ldos/linear-power-filters/article/1-
mic94300.html
http://www.micrel.com/index.php/en/products/power-
management-ics/ldos/linear-power-filters/article/3-
mic94310.html
September 11, 2014 10 Revision 2.1
Micrel, Inc.
MIC94310
Evaluation Board Schematic
Bill of Materials
Item Part Number Manufacturer Description Qty.
C1, C2 GRM155R61A105KE15D Murata(7) Capac itor , 1µF Ceramic, 10V, X7R, Size 0402 2
U1 MIC94310-xxYMT Micrel, Inc.
(8)
200mA LDO with Ripple Blocker Technology 1
Notes:
7. Murata: www.murata.com.
8. Micrel, Inc.: www.micrel.com.
September 11, 2014 11 Revision 2.1
Micrel, Inc.
MIC94310
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, Inc. is a leadi ng global manufacturer of I C solutions for the worldwide high perform ance linear and po wer, LAN, and t
iming &
communications
markets. The Company’s products include advanced mixed
-signal, analog & power semiconductors; high-
performance communication, clock
management,
MEMs-based clock oscillators & crystal-less clock generators, Ethernet switches, and physical layer transceiver ICs.
Company
customers include leading manufacturers of enterprise, consumer, industrial, mobile, telecommunications, automotive, and comp
uter products.
Corporation headquarters and state
-of-the-art wafer fabrication facilities are locat
ed in San Jose, CA, with regional sales and support offices and
advanced technol ogy design centers s ituated throughout the Americas, Europe, and As ia.
Additionally, the Company maintains an extensive network
of distribut ors and reps worldwide.
Micrel mak
es 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 righ
t 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 term
s and condit ions of sale for such produc ts, Micrel assumes no liabi lity
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 particul
ar purpose, merchantability, or infringement of any patent, copyright, or other intellectual propert y 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 s al e of Micrel Products for use in life support appliances, devi ces or systems is a Purchas er’s own risk and Purchaser agrees t o f ul l y
indemnify Micrel f or any damages resulting from suc
h use or sale.
© 2012 Micrel, Incorporated.
September 11, 2014 15 Revision 2.1
