an9526

A 5V to 3.3V, 7A, Synchronous Rectified Buck Regulator
Using the Intersil SynchroFET™ HIP5011
®
Application Note
September 1995
Introduction
The SynchroFET is ideal for implementing 5V to ≤3.3V or
3.3V to ≤2.9V converters. Efficiencies greater than 90% are
easily implemented, while achieving output powers in the
20W range. There are two versions of the SynchroFET. The
HIP5010 has a non-inverting PWM input and can be used
with controllers that drive single-ended N-Channel
MOSFETS. The HIP5011 has a inverting PWM input and
can be used with controllers that drive single-ended
P-Channel MOSFETs.
The Intersil SynchroFET is a new approach in partitioning a
synchronous rectified buck regulator. The device combines
power MOSFETs and drive circuitry to enable synchronous
rectification beyond 1MHz. Integrating the drive circuitry and
power MOSFETS in one silicon device offers numerous
advantages. These include increased frequency operation,
lower gate-charge, parasitic component reduction, precise
control of MOSFET switching via adaptive “shoot-through”
protection and elimination of the external Schottky rectifier
associated with a discrete solution. In addition, the tab of the
SynchroFET is tied to the substrate. This enables grounding
of the tab for greater thermal performance and lower EMI.
The device also operates in the continuous conduction mode
independent of load current. This results in a stable loop
response from no-load to full-load. A smaller inductor size is
attained with continuous conduction since the circuit will
never enter the discontinuous mode. What’s more,
discontinuous mode ringing at light loads is eliminated
further reducing EMI. To fully realize the ripple voltage
specification, the maximum allowable ripple current is
bounded by the equivalent series resistance (ESR) of the
output capacitance not the output inductance value. This
causes the inductor to be much smaller than in the standard
buck regulator. Furthermore, the SynchroFET can be driven
with a simple low cost voltage or current mode controller.
This eliminates costly application specific controller
interfacing.
HIP5011EVAL Board
The schematic for the HIP5011EVAL board is shown in
Figure 1. The circuit operates at a constant frequency of
400kHz. It accepts a 5V input and delivers a 3.3V output at
7ADC. The 12V supply provides bias power to the HIP5011
and powers the controller. As the schematic shows, the
HIP5011 can be interfaced with a very low cost controller. In
fact, this particular controller from Texas Instruments has no
MOSFET drivers making it low cost and a great companion
to the HIP5011. The board was designed to accept a surface
mount heat sink (Wakefield Engineering #216 series).
However, there is enough copper area on the evaluation
board where the heatsink is not necessary. Although,
noticeable improvement can be observed using the heatsink
within a path of airflow. The design process to follow will be
demonstrated for the 3.3V, 7A, HIP5011EVAL board
operating in a 25oC environment.
TP1-PWM
+12V
C13
1μF
2 U1
1
5
SCP VCC VO
3
CMP
DTC
4
7
RT GND FB
R2
3.32K
6
TL5001C 8
+
C15
1μF
C1
0.22μF
TP2-PHASE
+12V
+
C17
5600pF
R6
2.43K
+5V
2
VIN
L1
6
VIN
5
2μH
PWM
1
C14
PHASE
4
7
+
+
GND
1μF +
PHASE
C16
390pF
C5
C8
C6
C9
HIP5011
0.1μF
33μF 0.1μF 33μF
R4
1.47K
3
U2
+3.3V
7A
VCC
+
+
C10
33μF
C11 C12 C7
33μF 33μF 0.47μF
+
R3
3.4K
R5
15K
AN9526
+12V
C18
3900pF
+5V
+ C2
100μF
+ C3
4.7μF
FIGURE 1. SynchroFET DEMO-BOARD SCHEMATIC
1
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
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Application Note 9526
Designing the Output Filter
I
To determine the output inductor value, the duty cycle and
input current must be calculated. There are three resistive
elements within the SynchroFET circuit model shown in
Figure 2. From this model the equation for duty cycle is as
follows:
V O + I LOAD ( R W + R DSL )
D = ----------------------------------------------------------------------------V IN + I LOAD ( R DSL – R DSU )
(EQ. 1)
D = Duty Cycle
VO = Output Voltage
VIN = Input Voltage
ILOAD = Load Current
RW = Inductor Winding Resistance
RDSU = rDS(ON) of the Upper MOSFET
RDSL = rDS(ON) of the Lower MOSFET
VIN
RDSU
RW
L
VO
IN
= D
2
2
ΔΙ
ΔΙ
ΔΙ
ΔΙ
⎛I
– -----⎞ + ⎛ I
– -----⎞ • ⎛ I
+ -----⎞ + ⎛ I
+ -----⎞
⎝ LOAD 2 ⎠ ⎝ LOAD 2 ⎠ ⎝ LOAD 2 ⎠ ⎝ LOAD 2 ⎠
• -------------------------------------------------------------------------------------------------------------------------------------------------------------------3
(EQ. 2)
Before calculating the output inductance value, acceptable
ripple current needs to be determined. As stated earlier, to fully
realize the ripple voltage specification, the maximum allowable
ripple current is bounded by the ESR of the output capacitance.
In other words, the ESR of the output capacitance sets the
maximum ripple current allowable to meet the ripple voltage
specification. This is quite different from a standard buck
regulator. In a standard buck, the ripple current is limited by the
boundary between continuous and discontinuous mode
operation. The result of this boundary condition can cause the
inductor to be large, especially if the minimum load requirement
is low. In the synchronous rectified buck regulator, the
converter is always running in the continuous mode. Even at no
load! Therefore the ripple current can be made much larger,
limited only by the output capacitance ESR value which
ultimately sets the ripple voltage specification.
Choosing a ripple current equal to 20% of the rated output
current results in 1.4A of ripple current. For 10mV of ripple
voltage the minimum output capacitance and maximum ESR
requirements are:
ΔΙ O
C MIN = ---------------------------------8 • F S • ΔV O
(EQ. 3)
1.4
C MIN = ---------------------------------------------- = 44μF
8 • 400000 • 0.01
RDSL
FIGURE 2.
The following parameters are known:
VO = 3.3V
VIN = 5V
VINMAX = 5.25V
ILOAD = 7A
ΔV O
0.01
ESR = ------------ = ----------- = 0.007Ω
ΔΙ O
1.4
A polymer aluminum capacitor made by Panasonic and
Cornell Dubilier has very low ESR values. Their 33μF
capacitors have an ESR of 0.015Ω at a switching frequency
of 400kHz. Three of these 33μF capacitors in parallel will
yield 0.005Ω, meeting the requirements listed above.
The inductor can now be calculated keeping in mind that the
maximum ripple current occurs at the maximum input
voltage:
RDSU = 0.065Ω
RDSL = 0.068Ω
Assume that the winding resistance of the inductor is zero
since it is unknown at this time. Later this value can be
determined and the inductance can be recalculated.
( V INMAX – V DROP – V O ) • D • t
L = ------------------------------------------------------------------------------------ΔΙ O
(EQ. 4)
3.3 + 7 • ( 0 + 0.068 )
D = -------------------------------------------------------------------- = 0.716
5.25 + 7 • ( 0.068 – 0.065 )
The unknown parameters are:
2
2
⎛
( 7 – 0.7 ) + 7 – 0.7 • ( 7 + 0.7 ) + ( 7 + 0.7 ) ⎞
I IN = ⎜ 0.716 • ---------------------------------------------------------------------------------------------------------------⎟ = 5.02A
RW = 0Ω
⎝
ΔΙ = Ripple Current
IIN = RMS Input Current
The RMS input current can be calculated by using the
following equation:
2
3
⎠
Application Note 9526
Modeling the Error Amplifier
V DROP = I IN • ( R DSU + R W )
V DROP = 5.02 • ( 0.065 + 0 ) = 0.326V
–6
( 5.25 – 0.326 – 3.3 ) • 0.716 • 2.5 • 10
L = --------------------------------------------------------------------------------------------------------- = 2.08μH
1.4
From this calculation a 2μH inductor was chosen from
Coiltronics CTX2-4. This particular inductor has a DC
winding resistance of 0.008Ω. Running through the previous
equations with this winding resistance yields the following:
D = 0.727
I IN = 5.1A
V DROP = 0.372V
L = 2.05μH
Control Loop Stabilization
The output capacitance and ESR combination of C10, C11
and C12 results in the ESR zero being pushed out to
318kHz, making it unable to aide in loop stability. As a result,
a type-three compensation loop was implemented. The unity
gain crossover was chosen to be 1/10th the switching
frequency or 40kHz. Detailed implementation of control-loop
design and component synthesis is beyond the scope of this
text. However, references [3] and [5] do address this topic
further. Basic concepts covered here will enable proper
modeling and verification of the loop response. The loop was
simulated using Cadence’s Analog Workbench, however
any SPICE based modeling program can be used. The
model used is shown in Figure 3.
+
-
C18
C16
3900pF
390pF
R3
R6
C17
3.40K
2.43K
5600pF
A
AVOL
GAIN = 10000
BUFFER
GAIN = 1
1K
+
VIN
+
-
-
V
1μF
+
VIN
-
-
Modeling the Power Stage
The power stage begins with the pulse-width modulator gain
APWM. This gain comes from the compensation voltage
varying the duty cycle, which ultimately controls the output
voltage. Referencing the TL5001 data sheet, a graph depicts
compensation voltage variation at 400kHz. It is seen that the
compensation voltage variation is from 0.5V (0% duty cycle)
to 1.5V (100% duty cycle). The PWM gain is:
ΔV O
5–0
G PWM = ----------------------------- = ---------------------- = 5 = 14dB
ΔV OCOMP
1.5 – 0.5
V
Figure 4 shows the three separate curves. This top curve is
the open-loop response of the TL5001 error amplifier. Notice
that the unity gain crossover is 1.5MHz as specified in the
data sheet. The middle curve shows the LC filter gain
response which begins at 14dB due to the modulator gain.
The LC filter has a break frequency of 11kHz. The bottom
curve is the output filter phase response. The phase
attempts to traverse 180 degrees but is stymied by the ESR
zero at 318kHz.
+
VIN
-
0.04
+
-
B
2μH
V
0.008
99μF
0.47
0.005
R4
1.47K
FIGURE 3. HIP5011 CONTROL LOOP MODEL USING THE TL5001 CONTROLLER
3
(EQ. 5)
The remainder of the power stage simulation denotes the
SynchroFET rDS(ON) resistance, LC output filter with
associated inductor winding resistance, capacitance ESR
and full-load resistance.
APWM
GAIN = 5
2K
+
The parameters for the error amplifier are given in the
TL5001 data sheet. The first gain stage of the error amplifier
model is the open-loop gain stage AVOL. This is followed by
an RC network providing a one pole roll-off, yielding a unity
gain crossover of 1.5MHz. This is the minimum specified
bandwidth for the error amplifier. The next stage is a buffer
followed by the amplifiers output impedance. This completes
the model of the controller error amplifier.
0.47μF
Application Note 9526
100
ERROR AMP OPEN-LOOP GAIN RESPONSE
50
OUTPUT FILTER
GAIN RESPONSE
25
0
-25
120
-50
80
-75
OUTPUT FILTER
PHASE RESPONSE
-100
-125
-150
-175
-200
0.01
0.1
1
10
100
1000
10000
FREQUENCY (kHz)
FIGURE 4.
The schematic representation of the type-three
compensation network is shown in Figure 5. R3 and R4 set
the output voltage. Type three compensation components
are shown about the error amplifier model in Figure 3.
IN
R3
C17
R6
-
+
R4
OUT
VREF
This compensation scheme has two zeros and two poles
and is used when ESR values are too low to aide in the loop
stability, the case we have here. The two zeros of the
compensation loop cancel the two poles of the LC output
filter, while the two poles yield sufficient roll-off at higher
frequencies. The response of the compensation loop is
shown in Figure 6 showing two zeros located at 11kHz and
two poles at 160kHz. Also shown in Figure 6 is the open loop
gain response of the error amplifier.
60
ERROR AMP OPEN-LOOP
GAIN RESPONSE
GAIN (dB)
COMPENSATED
GAIN RESPONSE
-160
OVERALL PHASE
RESPONSE
-200
-240
-280
-360
0.001
0.01
0.1
FIGURE 6.
4
1000
o
θ JA = 30 C ⁄ W
It was also determined that the SynchroFET case could be
kept below 110oC at full load with a room temperature of
22oC. Therefore we can determine the total power
dissipated in the SynchroFET as:
• Conduction Losses
10
100
FREQUENCY (kHz)
100
Before getting into the details of the power loss analysis, the
HIP5011EVAL board was characterized for thermal
resistance. It was determined that with the amount of copper
on the board and the SynchroFET surface mounted to that
copper, the thermal resistance from junction to ambient was
approximately:
• Switching Losses
10
1
10
FIGURE 7.
• Gate Drive Power Losses
0.1
1
FREQUENCY (kHz)
This total power dissipation within the SynchroFET
culminates from three sources. These are:
20
0
0.01
-80
-120
TJ – TA
110 – 22
P T = ------------------- = ---------------------- = 2.93W
θ JA
30
40
30
-40
HIP5011 Power Loss Analysis
FIGURE 5.
50
OVERALL GAIN
RESPONSE
0
One final note. In the actual HIP5011EVAL board resistor
RX was removed from the compensation network of Figure
5, because in this case, it is somewhat superfluous. This
removes one of the poles in the transfer-function. This does
not present a problem since the natural roll-off response of
the error amplifier will aide the attenuation of the upper
frequencies. This is exemplified in Figure 6.
C16
RX
40
-320
Modeling the Compensation Network
C18
GAIN (dB) PHASE (DEGREES)
GAIN (dB) PHASE (DEGREES)
75
Finally, the combination of the compensation loop response
with the power train response yields the results shown in
Figure 7. Here is a stable overall loop response with a unity
gain crossover at 40kHz and a phase margin of nearly 45
degrees before the phase traverses 360 degrees.
1000
10000
Application Note 9526
Gate Drive Power Losses: The gate drive power losses
result in the power dissipated within the gate drivers. This
power is a result of displacing the charge on the gate-tosource capacitance CGS. The gate power is frequency
dependant and is determined by the following equation:
P G = ( Q GU • V GU + Q GL • V GL ) • F S
–9
7•5
P S = ------------ • 10 • 400000 = 70mW
2
P C = ( R DSU • D + R DSL • ( 1 – D ) ) • I
2
(EQ. 8)
The HIP5011 data sheet rDS(ON) vs Temperature curve
specifies that for a junction temperature of 110oC the value
of rDS(ON) will increase by a factor of 1.45. Therefore:
(EQ. 6)
QGU = Upper MOSFET gate charge = 7.43nC
R DSU = 1.45 • 0.039 = 0.057Ω
QGL = Lower MOSFET gate charge = 8.0nC
R DSL = 1.45 • 0.041 = 0.060Ω
VGU = Upper MOSFET gate voltage = 7V
VGL = Lower MOSFET gate voltage = 12V
2
P C = ( 0.057 • 0.727 + 0.060 • ( 1 – 0.727 ) ) • 7 = 2.83W
(EQ. 9)
The gate drive power loss is:
P G = ( 7.43 • 10
–9
• 7 + 8.0 • 10
–9
The total power loss of the SynchroFET at full load are:
• 12 ) • 400000 = 0.059mW
P T = P G + P S + P C = 0.059 + 0.07 + 2.83 = 2.96W
Switching Losses: The switching losses are caused by
crossover conduction during the switching interval and by
the output capacitance COSS being displaced. It turns out
that the power dissipation caused by the output capacitance
is very small compared to the conduction during switching
and can be neglected. The switching losses become:
I • V IN
P S = ----------------- • t SW • F S
2
This value matches very closely with the calculation of total
power dissipated using empirical data shown earlier.
SynchroFET Operation With +5V Only
It is possible to “bootstrap” the SynchroFET off of a single
+5V supply. To do this, five diodes and three capacitors are
used to generate a charge-pump from the switching action of
the converter. Using inexpensive 1N4148 diodes a VCC of
11.5V can be achieved. Using Schottky diodes in place of
the 1N4148’s, a VCC in excess of 12V can be realize. The
VCC voltage can be created from the charge-pump
technique shown in Figure 8.
(EQ. 7)
The switching transition tsw takes place in approximately
10ns. Therefore:
Conduction Losses: Conduction losses are simply I2R
losses. Conduction losses can be approximated as:
+5V
1N4148
1N4148
1N4148
+
1N4148
+
0.1μF
+
0.1μF
1μF
+5V
1N4148
1μF
+
3
5
PWM
4
VCC
PWM
+3.3V
7A
VIN 2
6
VIN
2μH
1
PHASE
7
GND
PHASE
HIP5011
+
0.1μF
33μF
0.1μF
FEEDBACK
FIGURE 8.
5
+
+
+
+
33μF
33μF
33μF
33μF
0.47μF
Application Note 9526
The component selection of the charge pump circuit
depends upon the switching frequency. The capacitors can
be tantalum or ceramic, ceramic being the lowest cost. Each
time charge is added to the capacitors (once every switching
cycle) current flows in the diode and is limited by the diode’s
forward on resistance. The time constant of this resistance
and the capacitor should be much less than the switching
period. If using P-N junction diodes the designer should
account for the reverse recovery losses when operating at
very high frequencies (FS > 500kHz). The SynchroFET will
begin switching when VCC is at least 4V. A diode from VIN to
VCC will provide 4.3V to VCC, satisfying the requirement for
switching to begin.
Layout Considerations
While the SynchroFET is highly integrated and performs
synchronous rectification transparent to the user, there is still
just cause for proper layout. This is especially true if
operation near or beyond 1MHz is planned. The critical
areas for layout are supplying input power to the device, the
phase connection and of course, ground. Figure 9 shows the
component, solder, via and silk-screen layout of the
HIP5011EVAL demo-board.
FIGURE 9A. SILK SCREEN
FIGURE 9B. COMPONENT
SIDE
FIGURE 9C. SOLDER SIDE
FIGURE 9D. SOLDER SIDE
Since a typical bench supply will be used to evaluate the demo
board performance, input bulk capacitors C2 and C3 decouple
the input inductance from the +5V and +12V sources. In an
actual embedded design, these may not be necessary.
High frequency input bypassing is performed by two pairs of
capacitors C5, C8 and C6, C9. One pair for each VIN
terminal. Each pair of capacitors needs to be as close to the
VIN terminals as possible. They also need to have a short
return path to ground. This arrangement will make a very
tight high frequency bypassing path (see Figure 9).
The input and output capacitors should be tied to the same
ground area. This ground area should be separate from the
controller analog ground. The actual feedback path should
consist of a separate ground and output power line from the
output terminals to the controller signal ground and feedback
terminal respectively.
The ground plane and input power plane should be as large
as possible to eliminate parasitic inductances. A large
ground plane will also aide thermal performance. Vias from
the top side ground area, to the bottom side ground area, will
transfer heat to a bottom side copper plane further improving
thermal performance.
6
Application Note 9526
+5V
+12V
3
VIN 2
6
VIN
5
PWM
1
PHASE
4
7
GND
PHASE
0.1μF
VCC
HIP5011
33μF
COUPLED INDUCTOR
VOUT
+
0.1μF
PWM
+
+
33μF
0.1μF
33μF
0.1μF
+
+
+5V
3
VIN 2
6
VIN
5
PWM
1
PHASE
4
7
GND
PHASE
0.1μF
VCC
HIP5011
33μF
+
0.1μF
+
FEEDBACK
FIGURE 10.
Parallel Operation
Parallel operation of two SynchroFETs is possible for
increased output current capability (an example of this is
shown in Figure 10). In addition to following proper layout
practices covered earlier there are several additional
requirements for parallel operation.
• The PWM drive signal must have very fast rise and fall
times because both SynchroFETs will not have the
same input threshold.
• Both SynchroFETs must be grounded to the same continuous ground plane. This ensures that the PWM-toground voltage is the same for both packages.
• The printed circuit board routing of VCC, VIN, and PWM
signal should be identical for both devices. This
ensures the input inductance on the board will match to
avoid delay mismatches.
• The two devices should have the identical thermal
design. This ensures thermal tracking for each device
and improves efficiency.
Performance
The performance of the HIP5011EVAL board proved to be
excellent. Figure 11 shows the phase voltage along with the
inductor current at no load. This shows the beauty of
continuous conduction. At no load the inductor current
traverses negative to maintain an average current of zero.
Also, the phase voltage is absent of severe ringing as in
discontinuous mode conduction.
The next two traces shown in Figures 12 and 13 are the
inductor current under transient conditions. In Figure 12,
the current is moving from no-load to full-load (7A). In Figure
7
13, the current moves from full-load to no-load. Again, notice
the negative current which speeds up transient response.
Figure 14 shows a load transient di/dt moving from no-load
to full-load, lasting 500μs and its effect on the output voltage.
The output voltage remains in specification during this
transient, for a total deviation of approximately 150mV.
In Figure 15 we have a short circuit condition. The short
circuit current is shown in the top trace. The lower trace is
the SCP control line, pin 5 on the TL5001. Its voltage
increases to disable the PWM drive, which it does very
nicely.
Shown in Figure 16 is the ripple voltage waveform at the full
load current. The ripple voltage is quite higher than
calculated. Possible reasons for this are additional contact
resistance between the part and the board along with
parasitic impedances.
Figure 17 shows the efficiency curve. From nearly 0.5A to
over 5.5A the efficiency is 90% or greater and reaches 95%
efficiency at 1.75A.
Finally, measurement on a network analyzer to determine
actual loop response is shown in Figure 18. Here the unity
gain crossover is at 60kHz with a phase margin of 75
degrees at full load. It was also measured at no load. At no
load the crossover frequency was measured to be 40kHz
and the phase margin was 50 degrees. As the load
increases, the unity gain crossover increases because at
higher current levels the inductance value of the output
inductor decreases. This pushes the output filter pole pair
further up the frequency scale.
Application Note 9526
TEK RUN: 50.0MS/s AVERAGE
TEK RUN: 5.00MS/s AVERAGE
6V
C1 FREQ
401.149kHz
4V
2V
0V
8A
2
6A
0.5A
0A
10A
4A
1
2A
-0.5A
0A
CH1 10.0mVΩ CH2 2.00VΩ
0.5A/DIV
M 1.00μs CH2 ∫
1
CH1 10.0mVΩ
2A/DIV
3.08V
FIGURE 11.
TEK RUN: 500kS/s AVERAGE
8A
10A
6A
8A
4A
6A
2A
1
4A
0A
2A
1
0A
100mV
2
0V
-2A
-100mV
M 10.0μs CH2 ∫
CH1 10.0mVΩ CH2 100mVΩ M 100μs CH1 ∫
Δ: 158mV @: 150mV
2A/DIV
-11.8mV
FIGURE 13.
20A
22.6V
FIGURE 12.
TEK RUN: 5.00MS/s AVERAGE
CH1 10.0mVΩ
2A/DIV
M 10.0μs CH2 ∫
14.4mV
FIGURE 14.
TEK RUN: 2.00kS/s AVERAGE TRIG?
TEK RUN: 50.0MS/s AVERAGE
15A
10A
40mV
5A
20mV
2
0A
1
0V
1V
-20mV
500mV
-40mV
2
0V
CH1 10.0mVΩ CH2 500mV
5A/DIV
M 25.0ms Ax 1 ∫
FIGURE 15.
8
1.06V
CH2 20.0mVΩ M 1.00μs CH2 ∫
FIGURE 16.
14.4mV
Application Note 9526
50
94
40
93
30
92
20
91
90
ILOAD = 7A
200
150
PHASE
100
50
10
GAIN
0
0
-50
89
-10
-100
88
-20
-150
87
-30
-200
86
0
1
2
3
4
LOAD CURRENT (A)
5
6
7
100Hz
FIGURE 17. EFFICIENCY vs LOAD CURRENT
1kHz
10kHz
PHASE (DEGREES)
95
GAIN (dB)
EFFICIENCY
96
100kHz
FIGURE 18.
Conclusion
References
The HIP5010 and HIP5011 SynchroFETs are a new
approach in partitioning a synchronous rectified buck
regulator. It has been demonstrated that a high performance
synchronous rectified buck regulator can be realized using a
very inexpensive controller. The SynchroFET facilitates the
design of such a converter by integrating the control and
power section into one device. Converters with output
powers greater than 20W and efficiencies in excess of 90%
can be easily implemented.
For Intersil documents available on the internet, see web site
http://www.intersil.com.
[1] HIP5010, HIP5011 Data Sheet, Intersil Corporation,
FN4029.
[2] Mike Walters, “An Integrated Synchronous-Rectifier
Power IC With Complementary-Switching”, Intersil
Corporation, TechBrief No. TB332.
[3] Designing With The TL5001C PWM Controller, Texas
Instruments Application Report #SLVA034.
[4] TL5001C Data Sheet, Texas Instruments, #SLVS084A.
[5] Abraham I. Pressman, Switching Power Supply Design,
McGraw-Hill, 1991.
9
Application Note 9526
Material List
ITEM
QUANTITY
DESIGNATOR
VALUE
1
1
C1
0.22μF, 50V Ceramic
2
1
C2
100μF, 10V Tantalum
3
1
C3
4.7μF, 50V Tantalum
4
2
C5, C6
0.1μF, 50V Ceramic
5
5
C8, C9, C10, C11, C12
33μF, 6.3V Aluminum Polymer, Cornel Dubilier
ESR330M0J1516
6
3
C13, C14, C15
1μF, 50V Tantalum
7
1
C7
0.47μF, 50V Ceramic
8
1
C16
390pF, 50V Ceramic
9
1
C17
5600pF, 50V Ceramic
10
1
C18
3900pF, 50V Ceramic
11
1
R2
3.32K, 1%
12
1
R3
3.4K, 1%
13
1
R4
1.47K, 1%
14
1
R5
15K, 1%
15
1
R6
2.43K, 1%
16
1
L1
2μH Inductor, CTX2-4 Coiltronics
17
2
TP1, TP2
Test-Point, Tektronix 131-4353-00
18
5
+5 IN, +12 IN, GND IN, 3.3V OUT, GND OUT
Terminal Post, Century Fasteners 1514-2
19
1
U1
TL5001C Texas Instruments
20
1
U2
HIP5011 Intersil Corporation
All Intersil U.S. products are manufactured, assembled and tested utilizing ISO9000 quality systems.
Intersil Corporation’s quality certifications can be viewed at www.intersil.com/design/quality
Intersil products are sold by description only. Intersil Corporation reserves the right to make changes in circuit design, software and/or specifications at any time without
notice. Accordingly, the reader is cautioned to verify that data sheets are current before placing orders. Information furnished by Intersil is believed to be accurate and
reliable. However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result
from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries.
For information regarding Intersil Corporation and its products, see www.intersil.com
10