MIC22700

MIC22700
1MHz, 7A Integrated Switch HighEfficiency Synchronous Buck Regulator
General Description
The Micrel MIC22700 is a high-efficiency, 7A, integrated
switch, synchronous buck (step-down) regulator. The
MIC22700 is optimized for highest efficiency, achieving
more than 95% efficiency while still switching at 1MHz
over a broad range. The device works with a small 1µH
inductor and 100µF output capacitor. The ultra-high speed
control loop keeps the output voltage within regulation
even under extreme transient load swings commonly
found in FPGAs and low-voltage ASICs. The output
voltage can be adjusted down to 0.7V to address all low
voltage power needs. The MIC22700 offers a full range of
sequencing and tracking options. The Enable/Delay pin
combined with the Power Good/POR pin allows multiple
outputs to be sequenced in any way during turn-on and
turn-off. The RC (Ramp Control™) pin allows the device to
be connected to another product in the MIC22xxx and/or
MIC68xxx family, to keep the output voltages within a
certain ∆V on start up.
®
The MIC22700 is available in a 24-pin 4mm x 4mm MLF
with a junction operating range from –40°C to +125°C.
Data sheets and support documentation can be found on
Micrel’s web site at: www.micrel.com.
Features
•
•
•
•
•
•
•
•
•
•
•
•
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Input voltage range: 2.6V to 5.5V
Output voltage adjustable down to 0.7V
Output load current up to 7A
Full sequencing and tracking capability
Power-on-Reset/Power Good output
Efficiency > 95% across a broad load range
Ultra-fast transient response
– Easy RC compensation
100% maximum duty cycle
Fully integrated MOSFET switches
Micropower shutdown
Thermal shutdown and current-limit protection
®
24-pin 4mm x 4mm MLF
–40°C to +125°C junction temperature range
Applications
•
•
•
•
•
•
High power density point-of-load conversion
Servers and routers
DVD recorders / Blu-Ray players
Computing peripherals
Base stations
FPGAs, DSP and low voltage ASIC power
Typical Application
MIC22700 7A 1MHz Synchronous Output Converter
Sequencing & Tracking
Ramp Control is a trademark of Micrel, Inc.
MLF and MicroLeadFrame are registered trademarks of Amkor Technology, 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
February 28, 2014
Revision 2.2
Micrel, Inc.
MIC22700
Ordering Information
Part Number
Voltage
MIC22700YML
Junction Temperature Range
Adjustable
–40° to +125°C
Package
24-Pin 4mm x4mm MLF
Lead Finish
®
Pb-Free
Note: MLF® is a GREEN RoHS compliant package. Lead finish is NiPdAu. Mold compound is Halogen Free.
Pin Configuration
®
24-Pin 4mm x 4mm MLF (ML)
Pin Description
Pin Number
Pin Name
1, 6, 13, 18
PVIN
Power Supply Voltage (Input): Requires bypass capacitor to GND.
Description
17
SVIN
Signal Power Supply Voltage (Input): Requires bypass capacitor-to-GND.
Enable/Delay (Input): When this pin is pulled higher than the enable threshold, the part will start
up. Below this voltage the device is in its low quiescent current mode. The pin has a 1µA current
source charging it to VIN. By adding a capacitor to this pin a delay may easily be generated. The
enable function will not operate with an input voltage lower than the min specified.
2
EN/DLY
4
RC
Ramp Control: Capacitor to ground from this pin determines slew rate of output voltage during
start-up. This can be used for tracking capability as well as soft start.
14
FB
Feedback: Input to the error amplifier, connect to the external resistor divider network to set the
output voltage.
15
COMP
5
POR/PG
7, 12, 19, 24
PGND
Power Ground: Ground
16
SGND
Signal Ground: Ground
3
DELAY
Delay (Input): Capacitor to ground sets internal delay timer. Timer delays power-on reset (POR)
output at turn-on and ramp down at turn-off.
8, 9, 10, 11,
20, 21, 22, 23
SW
EP
GND
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Compensation pin (Input): Place a RC to GND to compensate the device, see applications
section.
Power On Reset (Output): Open-drain output device indicates when the output is out of
regulation and is active after the delay set by the delay pin.
Switch (Output): Internal power MOSFET output switches.
Exposed Pad (Power): Must make a full connection to a GND plane for full output power to be
realized.
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MIC22700
Absolute Maximum Ratings(1)
Operating Ratings(2)
Supply Voltage (VIN) .......................................... –0.3V to 6V
Output Switch Voltage (VSW) ............................. –0.3V to 6V
Output Switch Current (ISW )....................... Internally Limited
Logic Input Voltage (VEN VFLG) .......................... –0.3V to VIN
Storage Temperature (Ts) ......................... –65°C to +150°C
(3)
ESD Rating .................................................................. 2kV
Lead Temperature (Soldering 10s) ............................ 260°C
Supply Voltage (VIN) ......................................... 2.6V to 5.5V
Junction Temperature (TJ) ..................–40°C ≤ TJ ≤ +125°C
Thermal Resistance
4x4 MLF-24 (θJC) ............................................... 14°C/W
4x4 MLF-24 (θJA) ............................................... 40°C/W
Electrical Characteristics(4)
TA = 25°C with VIN = VEN = 3.3V; VOUT = 1.8V, unless otherwise specified. Bold values indicate –40°C< TJ < +125°C.
Parameter
Supply Voltage Range
Under-Voltage Lockout Threshold
UVLO Hysteresis
Quiescent Current, PWM Mode
Shutdown Current
[Adjustable] Feedback Voltage
FB Pin Input Current
Current Limit
Output Voltage Line Regulation
Output Voltage Load Regulation
Maximum Duty Cycle
Switch ON-Resistance PFET
Switch ON-Resistance NFET
Oscillator Frequency
EN/DLY Threshold Voltage
EN/DLY Source Current
RC Pin IRAMP
Condition
Min.
2.6
2.4
Max.
Units
5.5
2.6
VIN = 2.6 to VIN = 5.5V
0.8
1.14
0.7
0.03
0.025
1
1.24
1
1.2
1.34
1.3
V
V
mV
µA
µA
V
nA
A
%
%
%
Ω
Ω
MHz
V
µA
Ramp Control Current
0.7
1
1.3
µA
1
2
µA
µA
(turn-on)
VEN =>1.34V; VFB = 0.9V (not switching)
VEN = 0V
± 2% (over temperature)
VFB = 0.5
VOUT 1.8V; VIN = 2.6 to 5.5V, ILOAD= 100mA
100mA < ILOAD < 7A, VIN = 3.3V
VFB ≤ 0.5V
ISW = 1000mA; VFB=0.5V
ISW = 1000mA; VFB=0.9V
Power On Reset IPG(LEAK)
VPORH = 5.5V; POR = High
Power On Reset VPG(LO)
Output Logic-Low Voltage (undervoltage condition),
IPOR = 5mA
Power On Reset VPG
Typ.
Threshold, % of VOUT below nominal
Hysteresis
Over-Temperature Shutdown
Over-Temperature Shutdown
Hysteresis
0.686
7
2.5
280
850
5
0.7
1
12.5
0.2
0.2
1300
10
0.714
16
100
130
7.5
10
mV
12.5
%
2
%
160
°C
20
°C
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 recommended.
4. Specification for packaged product only.
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MIC22700
Typical Characteristics
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MIC22700
Typical Characteristics (continued)
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MIC22700
Functional Characteristics
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MIC22700
Functional Characteristics (continued)
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MIC22700
Typical Circuits and Waveforms
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MIC22700
Functional Diagram
Figure 1. MIC22700 Block Diagram
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MIC22700
Functional Description
PVIN, SVIN
PVIN is the input supply to the internal 30mΩ P-Channel
Power MOSFET. This should be connected externally to
the SVIN pin. The supply voltage range is from 2.6V to
5.5V. A 22µF ceramic is recommended for bypassing
each PVIN supply.
FB
The feedback pin provides the control path to control the
output. A resistor divider connecting the feedback to the
output is used to adjust the desired output voltage. Refer
to the feedback section in the “Applications Information”
for more detail.
EN/DLY
This pin is internally fed with a 1µA current source to
VIN. A delayed turn on is implemented by adding a
capacitor to this pin. The delay is proportional to the
capacitor value. The internal circuits are held off until
EN/DLY reaches the enable threshold of 1.24V.
POR
This is an open drain output. A 47.5kΩ resistor can be
used for a pull up to this pin. POR is asserted high when
output voltage reaches 90% of nominal set voltage and
after the delay set by CDLY. POR is asserted low without
delay when enable is set low or when the output goes
below the –10% threshold. For a Power Good (PG)
function, the delay can be set to a minimum. This can be
done by removing the Delay capacitor.
RC
RC allows the slew rate of the output voltage to be
programmed by the addition of a capacitor from RC to
ground. RC is internally fed with a 1µA current source
and VOUT slew rate is proportional to the capacitor and
the 1µA source.
SW
This is the connection to the drain of the internal PChannel MOSFET and drain of the N-Channel MOSFET.
This is a high frequency high power connection;
therefore traces should be kept as short and as wide as
practical.
Delay
Adding a capacitor to this pin allows the delay of the
POR signal.
When VOUT reaches 90% of its nominal voltage, the
Delay pin current source (1µA) starts to charge the
external capacitor. At 1.24V, POR is asserted high.
SGND
Internal signal ground for all low power sections.
PGND
Internal ground connection to the source of the internal
N-Channel MOSFETs.
Comp
The MIC22700 uses an internal compensation network
containing a fixed frequency zero (phase lead response)
and pole (phase lag response) which allows the external
compensation network to be much simplified for stability.
The addition of a single capacitor and resistor will add
the necessary pole and zero for voltage mode loop
stability using low value, low ESR ceramic capacitors.
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MIC22700
performance, the inductor should be placed very close to
the SW nodes of the IC. For this reason, the heat of the
inductor is somewhat coupled to the IC, so it offers some
level of protection if the inductor gets too hot. It is
important to test all operating limits before settling on the
final inductor choice.
The size requirements refer to the area and height
requirements that are necessary to fit a particular
design. Please refer to the inductor dimensions on their
datasheet.
DC resistance is also important. While DCR is inversely
proportional to size, DCR can represent a significant
efficiency loss. Refer to the “Efficiency Considerations”
below for a more detailed description.
Application Information
The MIC22700 is a 7A Synchronous step down regulator
IC with a fixed 1 MHz, voltage mode PWM control
scheme. The other features include tracking and
sequencing control for controlling multiple output power
systems, power on reset.
Component selection
Input Capacitor
A minimum 22µF ceramic is recommended on each of
the PVIN pins for bypassing. X5R or X7R dielectrics are
recommended for the input capacitor. Y5V dielectrics,
aside from losing most of their capacitance over
temperature, they also become resistive at high
frequencies. This reduces their ability to filter out high
frequency noise.
Enable/DLY Capacitor
Enable/DLY sources 1µA out of the IC to allow a startup
delay to be implemented. The delay time is simply the
time it takes 1µA to charge CDLY to 1.25V. Therefore:
Output Capacitor
The MIC22700 was designed specifically for the use of
ceramic output capacitors. 100µF can be increased to
improve transient performance. Since the MIC22700 is
in voltage mode, the control loop relies on the inductor
and output capacitor for compensation. For this reason,
do not use excessively large output capacitors. The
output capacitor requires either an X7R or X5R
dielectric. Y5V and Z5U dielectric capacitors, aside from
the undesirable effect of their wide variation in
capacitance over temperature, become resistive at high
frequencies. Using Y5V or Z5U capacitors can cause
instability in the MIC22700.
TDLY =
Inductance
•
Rated current value
•
Size requirements
V
×I
Efficiency % =  OUT OUT
 VIN × I IN

 × 100

Maintaining high efficiency serves two purposes. It
decreases power dissipation in the power supply,
reducing the need for heat sinks and thermal design
considerations and it decreases consumption of current
for battery powered applications. Reduced current draw
from a battery increases the devices operating time,
critical in hand held devices.
There are mainly two loss terms in switching converters:
static losses and switching losses. Static losses are
2
simply the power losses due to VI or I R. For example,
power is dissipated in the high side switch during the on
cycle. Power loss is equal to the high side MOSFET
RDS(ON) multiplied by the RMS Switch Current squared
2
(ISW ). During the off cycle, the low side N-Channel
MOSFET conducts, also dissipating power. Similarly, the
inductor’s DCR and capacitor’s ESR also contribute to
2
the I R losses. Device operating current also reduces
efficiency by the product of the quiescent (operating)
current and the supply voltage. The current required to
drive the gates on and off at a constant 1MHz or 4MHz
frequency and the switching transitions make up the
switching losses.
•
DC resistance (DCR)
The MIC22700 is designed for use with a 0.47µH to
4.7µH inductor.
Maximum current ratings of the inductor are generally
given in two methods: permissible DC current and
saturation current. Permissible DC current can be rated
either for a 40°C temperature rise or a 10% loss in
inductance. Ensure the inductor selected can handle the
maximum operating current. When saturation current is
specified, make sure that there is enough margin that
the peak current will not saturate the inductor. The ripple
can add as much as 1.2A to the output current level. The
RMS rating should be chosen to be equal or greater than
the Current Limit of the MIC22700 to prevent
overheating in a fault condition. For best electrical
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1 × 10 −6
Efficiency considerations
Efficiency is defined as the amount of useful output
power, divided by the amount of power consumed.
Inductor Selection
Inductor selection will be determined by the following
(not necessarily in the order of importance):
•
1.24 ⋅ C DLY
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MIC22700
Figure 2 shows an efficiency curve. The portion, from 0A
to 1A, efficiency losses are dominated by quiescent
current losses, gate drive and transition losses. In this
case, lower supply voltages yield greater efficiency in
that they require less current to drive the MOSFETs and
have reduced input power consumption.
The following graph in Figure 3 illustrates the effects of
inductance value at light load.
95
Efficiency
vs. Inductance
90
85
L = 1µH
80
75
L = 4.7µH
70
65
60
55
50
0
200
400
600
800
OUTPUT CURRENT (mA)
Figure 3. Efficiency vs. Inductance
Compensation
The MIC22700 has a combination of internal and
external stability compensation to simplify the circuit for
small, high efficiency designs. In such designs, voltage
mode conversion is often the optimum solution. Voltage
mode is achieved by creating an internal 1MHz ramp
signal and using the output of the error amplifier to
modulate the pulse width of the switch node, thereby
maintaining output voltage regulation. With a typical gain
bandwidth of 100-200kHz, the MIC22700 is capable of
extremely fast transient responses.
The MIC22700 is designed to be stable with a typical
application using a 1µH inductor and a 100µF ceramic
(X5R) output capacitor. These values can be varied
dependent upon the tradeoff between size, cost and
efficiency, keeping the LC natural frequency
1
) ideally less than 26kHz to ensure
(
2 ×π × L ⋅C
stability can be achieved. The minimum recommended
inductor value is 0.47µH and minimum recommended
output capacitor value is 22µF. The tradeoff between
changing these values is that with a larger inductor,
there is a reduced peak-to-peak current which yields a
greater efficiency at lighter loads. A larger output
capacitor will improve transient response by providing a
larger hold up reservoir of energy to the output.
Figure 2. Efficiency Curve
The region, 1A to 7A, efficiency loss is dominated by
MOSFET RDS(ON) and inductor DC losses. Higher input
supply voltages will increase the Gate-to-Source voltage
on the internal MOSFETs, reducing the internal RDS(ON).
This improves efficiency by decreasing DC losses in the
device. All but the inductor losses are inherent to the
device. In which case, inductor selection becomes
increasingly critical in efficiency calculations. As the
inductors are reduced in size, the DC resistance (DCR)
can become quite significant. The DCR losses can be
calculated as follows:
2
LPD = IOUT × DCR
From that, the loss in efficiency due to inductor
resistance can be calculated as follows:
 
VOUT ⋅ I OUT
Efficiency Loss = 1 − 
  (VOUT ⋅ I OUT ) + LPD

 × 100


Efficiency loss due to DCR is minimal at light loads and
gains significance as the load is increased. Inductor
selection becomes a trade-off between efficiency and
size in this case.
Alternatively, under lighter loads, the ripple current due
to the inductance becomes a significant factor. When
light load efficiencies become more critical, a larger
inductor value maybe desired. Larger inductances
reduce the peak-to-peak inductor ripple current, which
minimize losses.
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MIC22700
The integration of one pole-zero pair within the control
loop greatly simplifies compensation. The optimum
values for CCOMP (in series with a 20kΩ resistor) are
shown below.
C
22-47µF
L
0.47µH
0*-10pF
†
47µF100µF
100µF470µF
22pF
33pF
1µH
0 -15pF
15-22pF
33pF
2.2µH
15-33pF
33-47pF
100-220pF
fundamental and harmonic frequencies are achieved.
Other methods of regulation, such as burst and skip
modes, have frequency spectrums that change with load
that can interfere with sensitive communication
equipment.
Sequencing and tracking
The MIC22700 provides additional pins to provide
up/down sequencing and tracking capability for
connecting multiple voltage regulators together.
Enable/DLY pin
The Enable pin contains a trimmed, 1µA current source
which can be used with a capacitor to implement a fixed
desired delay in some sequenced power systems. The
threshold level for power on is 1.24V with a hysteresis of
20mV.
* VOUT > 1.2V, † VOUT > 1V
Feedback
The MIC22700 provides a feedback pin to adjust the
output voltage to the desired level. This pin connects
internally to an error amplifier. The error amplifier then
compares the voltage at the feedback to the internal
0.7V reference voltage and adjusts the output voltage to
maintain regulation. The resistor divider network for a
desired VOUT is given by:
R2 =
Delay Pin
The Delay pin also has a 1µA trimmed current source
and a 1µA current sink which acts with an external
capacitor to delay the operation of the Power On Reset
(POR) output. This can be used also in sequencing
outputs in a sequenced system, but with the addition of a
conditional delay between supplies; allowing a first up,
last down power sequence.
After Enable is driven high, VOUT will start to rise (rate
determined by RC capacitor). As the FB voltage goes
above 90% of its nominal set voltage, Delay begins to
rise as the 1µA source charges the external capacitor.
When the threshold of 1.24V is crossed, POR is
asserted high and Delay continues to charge to a
voltage VDD. When FB falls below 90% of nominal, POR
is asserted low immediately. However, if enable is driven
low, POR will fall immediately to the low state and Delay
will begin to fall as the external capacitor is discharged
by the 1µA current sink. When the threshold of VDD1.24V is crossed, VOUT will begin to fall at a rate
determined by the RC capacitor. As the voltage change
in both cases is 1.24V, both rising and falling delays are
1.24 ⋅ C DLY
matched at TPOR =
1 × 10 −6
R1
 VOUT


− 1
 VREF

where VREF is 0.7V and VOUT is the desired output
voltage. A 10kΩ or lower resistor value from the output
to the feedback is recommended since large feedback
resistor values increase the impedance at the feedback
pin, making the feedback node more susceptible to
noise pick-up. A small capacitor (50pF – 100pF) across
the lower resistor can reduce noise pick-up by providing
a low impedance path to ground.
PWM Operation
The MIC22700 is a voltage mode, pulse width
modulation (PWM) controller. By controlling the ratio of
on-to-off time, or duty cycle, a regulated DC output
voltage is achieved. As load or supply voltage changes,
so does the duty cycle to maintain a constant output
voltage. In cases where the input supply runs into a
dropout condition, the MIC22700 will run at 100% duty
cycle.
The MIC22700 provides constant switching at 1MHz with
synchronous internal MOSFETs. The internal MOSFETs
include a high-side P-Channel MOSFET from the input
supply to the switch pin and an N-Channel MOSFET
from the switch pin-to-ground. Since the low-side NChannel MOSFET provides the current during the off
cycle, very low power is dissipated during the off period.
PWM control provides fixed frequency operation. By
maintaining a constant switching frequency, predictable
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RC pin
The RC pin provides a trimmed 1µA current source/sink
similar to the Delay Pin for accurate ramp up (soft start)
and ramp down control. This allows the MIC22700 to be
used in systems requiring voltage tracking or ratio-metric
voltage tracking at startup.
There are two ways of using the RC pin:
1. Externally driven from a voltage source
2. Externally attached capacitor sets output ramp
up/down rate
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MIC22700
Normal Tracking:
In the first case, driving RC with a voltage from 0V to
VREF will program the output voltage between 0 and
100% of the nominal set voltage.
In the second case, the external capacitor sets the ramp
up and ramp down time of the output voltage. The time
0.7 ⋅ C RC
where TRAMP is the time
is given by TRAMP =
1 × 10 −6
from 0 to 100% nominal output voltage.
Sequencing & Tracking examples
There are four distinct variations which are easily
implemented using the MIC22700. The two sequencing
variations are Delayed and Windowed. The two tracking
variants are Normal and Ratio Metric. The following
diagrams illustrate methods for connecting two
MIC22700’s to achieve these requirements.
Sequencing:
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MIC22700
Ratio Metric Tracking:
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An alternative method here shows an example of a VDDQ
and VTT solution for a DDR memory power supply. Note
that POR is taken from Vo1 as POR2 will not go high.
This is because POR is set high when FB > 0.9⋅VREF. In
this example, FB2 is regulated to ½⋅VREF:
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MIC22700
Where:
Current Limit
The MIC22700 is protected against overload in two
stages. The first is to limit the current in the P-channel
switch; the second is over temperature shutdown.
Current is limited by measuring the current through the
high side MOSFET during its power stroke and
immediately switching off the driver when the preset limit
is exceeded.
The circuit in Figure 4 describes the operation of the
current limit circuit. Since the actual RDSON of the PChannel MOSFET varies part-to-part, over temperature
and with input voltage, simple IR voltage detection is not
employed. Instead, a smaller copy of the Power
MOSFET (Reference FET) is fed with a constant current
which is a directly proportional to the factory set current
limit. This sets the current limit as a current ratio and
thus, is not dependent upon the RDSON value. Current
limit is set to nominal value. Variations in the scale factor
K between the Power PFET and the reference PFET
used to generate the limit threshold account for a
relatively small inaccuracy.
•
PDISS is the power dissipated within the MLF
package and is typically 1.5W at 7A load. This
has been calculated for a 1µH inductor and
details can be found in table 1 below for
reference.
•
RθJA is a combination of junction to case thermal
resistance (RθJC) and Case-to-Ambient thermal
resistance (RθCA), since thermal resistance of
the solder connection from the ePAD to the PCB
is negligible; RθCA is the thermal resistance of
the ground plane to ambient, so RθJA = RθJC +
RθCA.
®
VIN
VOUT
@7A
0.7V
2.6V
3.3V
3.6V
4.5V
5.5V
2.073
1.884
1.836
1.784
1.791
1.2V
2.133
1.896
1.853
1.786
1.796
1.8V
2.207
1.934
1.873
1.814
1.826
2.5V
—
1.953
1.881
1.797
1.803
3.3V
—
—
1.423
1.79
1.789
Table 1. Power Dissipation (W) for 7A output
•
TAMB is the Operating Ambient temperature.
Example:
The Evaluation board has two copper planes
contributing to an RθJA of approximately 25°C/W. The
o
worst case RθJC of the MLF 4x4 is 14 C/W.
Figure 4. Current Limit Detail
RθJA = RθJC + RθCA
o
RθJA = 14 + 25 = 39 C/W
Thermal Considerations
®
The MIC22700 is packaged in the MLF 4mm x 4mm, a
package that has excellent thermal performance
equaling that of the larger TSSOP packages. This
maximizes heat transfer from the junction to the exposed
pad (ePAD) which connects to the ground plane. The
size of the ground plane attached to the exposed pad
determines the overall thermal resistance from the
junction to the ambient air surrounding the printed circuit
board. The junction temperature for a given ambient
temperature can be calculated using:
To calculate the junction temperature for a 50°C
ambient:
TJ = TAMB+PDISS . RθJA
TJ = 50 + (1.5 x 39)
TJ = 109°C
This is below the maximum of 125°C.
TJ = TAMB + PDISS · RθJA
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Evaluation Board Schematic
Bill of Materials
Item
Part Number
TDK
08056D226MAT
AVX
GRM21BR60J226ME39L
Murata
GRM188R71H103KA01D
Open(VJ0603Y102KXQCW1BC)
C6
C8
C9
C10, C11
C12
(2)
22µF/6.3V, 0805, Ceramic Capacitor
5
Murata
(4)
10nF, 0603, Ceramic Capacitor
1
Vishay
1nF, 0603, Ceramic Capacitor
Murata
1000pF/50V, X7R, 0603, Ceramic Capacitor
Open(C1608C0G1H102J)
TDK
1000pF/50V, COG, 0603, Ceramic Capacitor
VJ0603Y102KXQCW1BC
Vishay
1nF, 0603, Ceramic Capacitor,
GRM188R71H102KA01D
Murata
1000pF/50V, X7R, 0603, Ceramic Capacitor
C1608C0G1H102J
TDK
1000pF/50V, COG, 0603, Ceramic Capacitor
GRM1555C1H390JZ01D
Murata
VJ0402A390KXQCW1BC
39pF/50V, COG, 0402, Ceramic Capacitor
BC Components
(5)
39pF /10V, 0402, Ceramic Capacitor
C3216X5R0J476M
TDK
47µF/6.3V, X5R, 1206, Ceramic Capacitor
GRM31CR60J476ME19
Murata
47µF/6.3V, X5R, 1206, Ceramic Capacitor
GRM31CC80G476ME19L
Murata
47µF/4V, X6S, 1206, Ceramic Capacitor
VJ0402A101KXQCW1BC
Vishay
100pF, 0603, Ceramic Capacitor
GRM1555C1H101JZ01D
Murata
100pF/50V, COG, 0402, Ceramic Capacitor
SS2P2L
Vishay
DFLS220
SPM6530T-1R0M120
February 28, 2014
HCP0704-1R0-R
Qty.
(3)
Open(GRM188R71H102KA01D)
D1
L1
Description
(1)
C2012X5R0J226M
C1, C2, C3,
C4, C5
C7, C13
Manufacturer
Diodes, Inc.
(6)
TDK
Coiltronics
Schottky Diode, 2A, 20V
1µH, 12A, size 7x6.5x3mm
(7)
1µH, 12A, size 6.8x6.8x4.2mm
17
1
1
1
2
1
1
1
Revision 2.2
Micrel, Inc.
MIC22700
Bill of Materials (Continued)
Item
Part Number
Manufacturer
R1
CRCW06031101FKEYE3
Vishay
Resistor, 1.1kΩ, 0603, 1%
1
R2
CRCW04026980FKEYE3
Vishay
Resistor, 698Ω, 0603, 1%
1
R3
CRCW06034752FKEYE3
Vishay
Resistor, 47.5kΩ, 0603, 1%
1
R4
CRCW04022002FKEYE3
Vishay
Resistor, 20kΩ, 0402, 1%
1
R5
Open(CRCW06031003FRT1)
Vishay
Resistor, 100kΩ, 0603, 1%
1
Open(2N7002E)
Vishay
Signal MOSFET – SOT-23-6
1
Open(CMDPM7002A)
Central
(8)
Semiconductor
Integrated 7A Synchronous Buck Regulator
1
Q1
U1
MIC22700YML
(9)
Micrel
Description
Qty.
Notes:
1.
TDK: www.tdk.com
2.
AVX: www.avx.com
3.
Murata: www.murata.com
4.
Vishay: www.vishay.com
5.
This part is now available through Vishay.
6.
Diodes, Inc.: www.diodes.com
7.
Coiltronics: www.coiltronics.com
8.
9.
Central Semiconductor: www.centralsemi.com
Micrel, Inc.: www.micrel.com
February 28, 2014
18
Revision 2.2
Micrel, Inc.
MIC22700
PCB Layout Recommendations
Top Silk
Top Layer
February 28, 2014
19
Revision 2.2
Micrel, Inc.
MIC22700
PCB Layout Recommendations (Continued)
Bottom Silk
Bottom Layer
February 28, 2014
20
Revision 2.2
Micrel, Inc.
MIC22700
Package Information
®
24-Pin 4mm x 4mm MLF (ML)
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.
© 2009 Micrel, Incorporated.
February 28, 2014
21
Revision 2.2