Fairchild FAN2108MPX Tinybuckâ ¢ 3-24v input, 8a, high-efficiency, integrated synchronous buck regulator Datasheet

FAN2108 — TinyBuck™
3-24V Input, 8A, High-Efficiency, Integrated Synchronous
Buck Regulator
Features
Description
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Wide Input Voltage Range: 3V-24V
The FAN2108 TinyBuck™ is a highly efficient, small
footprint, 8A, synchronous buck regulator.
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Over 95% Peak Efficiency
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Internal Bootstrap diode
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Internal Soft-Start
Wide Output Voltage Range: 0.8V to 80% VIN
8A Output Current
Programmable Frequency Operation: 200KHz to
600KHz
Integrated Schottky Diode on Low-side MOSFET
Boosts Efficiency
External compensation, programmable switching
frequency, and current limit features allow design
optimization and flexibility.
The summing current mode modulator uses lossless
current sensing for current feedback and over-current
protection. Voltage feedforward helps operation over a
wide input voltage range.
Power-Good Signal
Pre-Bias Startup
Accepts Ceramic Capacitors on Output
External Compensation for Flexible Design
Input Under-Voltage Lockout
Programmable Current Limit
Under-Voltage, Over-Voltage, and Thermal
Shutdown Protections
5x6mm, 25-Pin, 3-Pad MLP Package
The FAN2108 contains both synchronous MOSFETs
and a controller/driver with optimized interconnects in
one package, which enables designers to solve highcurrent requirements in a small area with minimal
external components.
Fairchild’s advanced BiCMOS power process,
combined with low-RDS(ON) internal MOSFETs and a
thermally efficient MLP package, provide the ability to
dissipate high power in a small package.
Output over-voltage, under-voltage, and thermal
shutdown protections help protect the device from
damage during fault conditions. FAN2108 prevents prebiased output discharge during startup in point-of-load
applications.
Applications
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Servers
Point-of-Load Regulation
High-End Computing Systems
Graphics Cards
Battery-Powered Equipment
Set-Top Boxes
Ordering Information
Part Number
Operating
Temperature Range
Package
Eco
Status
Packing
Method
FAN2108MPX
FAN2108EMPX
-10°C to 85°C
-40°C to 85°C
Molded Leadless Package (MLP) 5x6mm
Molded Leadless Package (MLP) 5x6mm
Green
Green
Tape and Reel
Tape and Reel
For Fairchild’s definition of “green” Eco Status, please visit: http://www.fairchildsemi.com/company/green/rohs_green.html.
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
www.fairchildsemi.com
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
September 2008
Figure 1. Typical Application Diagram
Block Diagram
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
Typical Application
Figure 2. Block Diagram
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
www.fairchildsemi.com
2
Figure 3. MLP 5x6mm Pin Configuration (Bottom View)
Pin Definitions
Pin #
Name
Description
P1, 6-12
SW
Switching Node.
P2, 2-5
VIN
Power Input Voltage. Connect to the main input power source.
P3, 21-23
PGND
Power Ground. Power return and Q2 source.
1
BOOT
High-Side Drive BOOT Voltage. Connect through capacitor (CBOOT) to SW. The IC
includes an internal synchronous bootstrap diode to recharge the capacitor on this pin to
VCC when SW is LOW.
13
PGOOD
Power-Good Flag. An open-drain output that pulls LOW when FB is outside a ±10% range
of the reference. PGOOD does not assert HIGH until the fault latch is enabled.
14
EN
ENABLE. Enables operation when pulled to logic HIGH or left open. Toggling EN resets the
regulator after a latched fault condition. This input has an internal pull-up when the IC is
functioning normally. When a latched fault occurs, EN is discharged by a current sink.
15
VCC
16
AGND
17
ILIM
Current Limit. A resistor (RILIM) from this pin to AGND can be used to program the currentlimit trip threshold lower than the default setting.
18
R(T)
Oscillator Frequency. A resistor (RT) from this pin to AGND sets the PWM switching
frequency.
19
FB
Output Voltage Feedback. Connect through a resistor divider to the output voltage.
20
COMP
Compensation. Error amplifier output. Connect the external compensation network
between this pin and FB.
24
NC
25
RAMP
Input Bias Supply for IC. The IC’s logic and analog circuitry are powered from this pin.
Analog Ground. The signal ground for the IC. All internal control voltages are referred to
this pin. Tie this pin to the ground island/plane through the lowest impedance connection.
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
Pin Configuration
No Connect. This pin is not used.
Ramp Amplitude. A resistor (RRAMP) connected from this pin to VIN sets the ramp amplitude
and provides voltage feedforward functionality.
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
www.fairchildsemi.com
3
Stresses exceeding the absolute maximum ratings may damage the device. The device may not function or be
operable above the recommended operating conditions and stressing the parts to these levels is not recommended.
In addition, extended exposure to stresses above the recommended operating conditions may affect device
reliability. The absolute maximum ratings are stress ratings only.
Parameter
Conditions
Min.
VIN to PGND
VCC to AGND
AGND=PGND
SW to PGND
Continuous
ESD
28
V
6
V
V
-0.3
6.0
V
-0.5
24.0
V
-5
30
V
-0.3
VCC+0.3
V
Transient (t < 20ns, f < 600KHz)
All other pins
Unit
35
BOOT to PGND
BOOT to SW
Max.
Human Body Model, JEDEC JESD22-A114
kV
2
Charged Device Model, JEDEC JESD22-C101
2.5
Recommended Operating Conditions
The Recommended Operating Conditions table defines the conditions for actual device operation. Recommended
operating conditions are specified to ensure optimal performance to the datasheet specifications. Fairchild does not
recommend exceeding them or designing to absolute maximum ratings.
Symbol
Parameter
Conditions
Min.
Typ.
Max.
Unit
5.0
VCC
Bias Voltage
VCC to AGND
4.5
5.5
V
VIN
Supply Voltage
VIN to PGND
3
24
V
TA
Ambient Temperature
FAN2108MPX
-10
+85
°C
FAN2108EMPX
-40
+85
°C
TJ
Junction Temperature
+125
°C
f
Switching Frequency
600
kHz
Max.
Unit
+150
°C
Thermal Information
Symbol
TSTG
Parameter
Min.
Storage Temperature
Typ.
-65
TL
Lead Soldering Temperature, 10 Seconds
+300
°C
TVP
Vapor Phase, 60 Seconds
+215
°C
Infrared, 15 Seconds
+220
°C
TI
P1 (Q2)
θJC
θJ-PCB
PD
Thermal Resistance: Junction-to-Case
Power Dissipation, TA=25°C
°C/W
P2 (Q1)
7
°C/W
P3
4
°C/W
35
°C/W
Thermal Resistance: Junction-to-Mounting Surface
(1)
4
(1)
2.8
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
Absolute Maximum Ratings
W
Note:
1. Typical thermal resistance when mounted on a four-layer, two-ounce PCB, as shown in Figure 24. Actual results
are dependent on mounting method and surface related to the design.
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
www.fairchildsemi.com
4
Electrical specifications are the result of using the circuit shown in Figure 1 unless otherwise noted.
Symbol
Parameter
Conditions
Min.
Typ. Max. Unit
Power Supplies
ICC
VUVLO
VCC Current
SW=Open, FB=0.7V, VCC=5V,
fSW =600KHz
8
12
mA
Shutdown: EN=0, VCC=5V
7
10
µA
4.3
4.5
V
Rising VCC
VCC UVLO Threshold
4.1
Hysteresis
300
mV
Oscillator
f
tON
VRAMP
tOFF
Frequency
Minimum On-Time
255
300
345
KHz
RT=24KΩ
540
600
660
KHz
50
65
ns
(2)
Ramp Amplitude, peak-to–peak
Minimum Off-Time
RT=50KΩ
16VIN, 1.8VOUT, RT=30KΩ,
RRAMP=200KΩ
0.53
(2)
100
V
150
ns
Reference
VFB
Reference Voltage (see Figure 4 for
Temperature Coefficient)
FAN2108MPX, 25°C
794
800
806
mV
FAN2108EMPX, 25°C
795
800
805
mV
80
85
dB
12
15
MHz
Error Amplifier
G
BW
VCOMP
ISINK
ISOURCE
IBIAS
DC Gain
(2)
Gain Bandwidth Product
(2)
VCC=5V
Output Voltage
0.4
3.2
V
Output Current, Sourcing
VCC=5V, VCOMP=2.2V
1.5
2.2
mA
Output Current, Sinking
VCC=5V, VCOMP=1.2V
0.8
1.2
mA
FB Bias Current
VFB=0.8V, 25°C
-850
-650 -450
nA
Protection and Shutdown
ILIM
Current Limit
IILIM
ILIM Current
TTSD
Over-Temperature Shutdown
THYS
Over-Temperature Hysteresis
RILIM Open at 25°C (see Circuit
Description)
12
15
18
A
-11
-10
-9
µA
Internal IC Temperature
+155
°C
+30
°C
VOVP
Over-Voltage Threshold
Two Consecutive Clock Cycles
110
115
121
%VOUT
VUVLO
Under-Voltage Shutdown
16 Consecutive Clock Cycles
68
73
78
%VOUT
VFLT
Fault Discharge Threshold
Measured at FB Pin
250
mV
VFLT_HYS
Fault Discharge Hysteresis
Measured at FB Pin (VFB ~500mV)
250
mV
5.3
ms
6.7
ms
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
Electrical Specifications
Soft-Start
tSS
VOUT to Regulation (T0.8)
tEN
Fault Enable/SSOK (T1.0)
Frequency=600KHz
Note:
2. Specifications guaranteed by design and characterization; not production tested.
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
www.fairchildsemi.com
5
Recommended operating conditions are the result of using the circuit shown in Figure 1 unless otherwise noted.
Symbol
Parameter
Conditions
Min. Typ. Max.
Unit
EN Threshold, Rising
1.35
V
EN Hysteresis
250
mV
800
KΩ
1
µA
Control Functions
VEN_R
VEN_HYS
REN
EN Pull-Up Resistance
IEN
EN Discharge Current
RFB
FB OK Drive Resistance
VPG
PGOOD Threshold
VPG_L
PGOOD Output Low
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
Auto-Restart Mode
2.00
800
FB < VREF
-14
-11
-8
FB > VREF
+7
+10
+13.5
IOUT < 2mA
0.4
Ω
%VREF
V
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
Electrical Specifications (Continued)
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6
1.20
1.005
1.10
I FB
V FB
1.010
1.000
0.995
1.00
0.90
0.990
0.80
-50
0
50
100
150
-50
0
Temperature (oC)
Figure 4. Reference Voltage (VFB)
vs. Temperature, Normalized
1200
1.01
Frequency
Frequency (KHz)
150
1.02
900
600
600KHz
1.00
300KHz
0.99
300
0.98
0
0
20
40
60
80
100
120
-50
140
0
RT (KΩ)
100
150
Temperature ( C)
Figure 7.
1.04
1.2
1.02
I ILIM
1.4
Q1 ~0.32%/°C
1
50
o
Figure 6. Frequency vs. RT
RDS
100
Figure 5. Reference Bias Current (IFB)
vs. Temperature, Normalized
1500
Q2 ~0.35%/°C
Frequency vs. Temperature, Normalized
1.00
0.98
0.8
0.6
-50
50
Temperature (oC)
0.96
0
50
100
150
-50
50
100
150
o
Temperature ( C)
Temperature (°C)
Figure 9.
Figure 8. RDS vs. Temperature, Normalized
(VCC=VGS=5V)
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
0
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
Typical Characteristics
ILIM Current (IILIM) vs. Temperature,
Normalized
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Figure 10. Application Circuit: 1.8VOUT, 500KHz
Typical Performance Characteristics
Typical operating characteristics using the circuit shown in Figure 10. VIN=12V, VCC=5V, unless otherwise specified.
0
Efficiency @ Vo=1.8V, fsw=500KHz, Ta=25 C
0
Efficiency @ Vo=3.3V, fsw=300KHz, Ta=25 C
100
95
95
Efficiency (%)
Efficiency (%)
90
85
Vin=8V
Vin=12V
80
Vin=16V
Vin=20V
75
70
2
Vin=10V
Vin=12V
80
Vin=14V
4
6
Vin=20V
70
8
0
Load Current (A)
Figure 11.
Vin=5V
85
75
Vin=24V
0
90
1.8VOUT Efficiency Over VIN vs. Load
2
4
Load Current (A)
6
8
Figure 12. 3.3VOUT Efficiency Over VIN vs. Load
Efficiency@ Vin=12V, Vo=1.8V
Load Regulation @ Vo=0.8V, 500kHz, 25°C
0.8012
Vin=8V
0.801
90
Output Voltage (V)
Efficiency (%)
95
85
80
300KHz
500KHz
75
600KHz
Vin=12V
0.8008
Vin=16V
0.8006
Vin=20V
0.8004
Vin=24V
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
Application Circuit
0.8002
0.8
0.7998
0.7996
70
0.7994
0
1
2
3
4
5
6
7
0.7992
8
0
Load Current (A)
2
3
4
5
6
7
8
Load Current (A)
Figure 13. 1.8VOUT Efficiency Over Frequency
vs. Load
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
1
Figure 14. 0.8VOUT Load Regulation Over VIN
vs. Load
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8
Typical operating characteristics using the circuit shown in Figure 10. VIN=12V, VCC=5V, unless otherwise specified.
VOUT
VOUT
SW
PGOOD
EN
EN
Figure 15. Startup, 3A Load
Figure 16. Startup with 1V Pre-Bias on Vout
SW
VOUT
PGOOD
EN
EN
Figure 17. Shutdown, 1A Load
Figure 18.
Restart on Fault
HS and LS MOSFET Temperature
90
VOUT
LSFET@ 20Vin
T emp e ra tu re ( ° C)
80
IOUT
LSFET@ 12Vin
HSFET@ 20Vin
70
HSFET@ 12Vin
60
50
40
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
Typical Performance Characteristics (Continued)
30
20
0
2
4
6
8
Load Current (A)
Figure 20. MOSFET Temperature – Still Air at Room
Temperature
Figure 19. Transient Response, 2-8A Load
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
www.fairchildsemi.com
9
Initialization
Soft-Start
Once VCC exceeds the UVLO threshold and EN is
HIGH, the IC checks for an open or shorted FB pin
before releasing the internal soft-start ramp (SS).
Once internal SS ramp has charged to 0.8V (T0.8), the
output voltage is in regulation. Until SS ramp reaches
1.0V (T1.0), the fault latch is inhibited.
If R1 is open (Figure 1), the error amplifier output
(COMP) is forced LOW and no pulses are generated.
After the SS ramp times out (T1.0), an under-voltage
latched fault occurs.
To avoid skipping the soft-start cycle, it is necessary to
apply VIN before VCC reaches its UVLO threshold.
Soft-start time is a function of oscillator frequency.
If the parallel combination of R1 and RBIAS is ≤ 1KΩ, the
internal SS ramp is not released and the regulator does
not start.
EN
1.35V
2400 CLKs
0.8V
Bias Supply
FB
The FAN2108 requires a 5V supply rail to bias the IC
and provide gate-drive energy. Connect a ≥ 1.0µf X5R
or X7R decoupling capacitor between VCC and PGND.
Since VCC is used to drive the internal MOSFET gates,
supply current is frequency and voltage dependent.
Approximate VCC current (ICC) is calculated by:
ICC ( mA ) = 4.58 + [(
VCC − 5
+ 0.013 ) • (f − 128)]
227
SS
(1)
3200 CLKs
T0.8
where frequency (f) is expressed in KHz.
4000 CLKs
T1.0
Enable
Figure 21. Soft-Start Timing Diagram
FAN2108 has an internal pull-up to enable pin so that
the IC is enabled once VCC is applied. Connecting a
small capacitor across EN and AGND delays the rate of
voltage rise on the EN pin. EN pin also serves for the
restart whenever a fault occurs (refer to the AutoRestart section). For applications where sequencing is
required, FAN2108 can be enabled (after the VCC
comes up) with external control, as shown in Figure 20.
The regulator does not allow the low-side MOSFET to
operate in full synchronous rectification mode until
internal SS ramp reaches 95% of VREF (~0.76V). This
helps the regulator to start on a pre-biased output and
ensures that inductor current does not "ratchet" up
during the soft-start cycle.
VCC UVLO or toggling the EN pin discharges the SS and
resets the IC.
FAN2108
14 EN
Setting the Output Voltage
The output voltage of the regulator can be set from 0.8V
to 80% of VIN by an external resistor divider (R1 and
RBIAS in Figure 1).
3.3n
The internal reference is 0.8V with 650nA, sourced from
the FB pin to ensure that, if the pin is open, the
regulator does not start.
Figure 20. Enabling with External Control
Setting the Frequency
The external resistor divider is calculated using:
Oscillator frequency is determined by an external resistor,
RT, connected between the R(T) pin and AGND.
Resistance is calculated by:
RT (KΩ ) =
Fault
Latch
Enable
1.0V
0.8V
(10 6 / f ) − 135
65
V
− 0.8V
0.8V
= OUT
+ 650nA
RBIAS
R1
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
Circuit Description
(3)
Connect RBIAS between FB and AGND.
(2)
where RT is in KΩ and frequency (f) is in KHz.
The regulator cannot start if RT is left open.
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
www.fairchildsemi.com
10
Typically the inductor is set for a ripple current (ΔIL) of
10% to 35% of the maximum DC load. Regulators
requiring fast transient response use a value on the
high side of this range; while regulators that require very
low output ripple and/or use high-ESR capacitors
restrict allowable ripple current.
L=
VOUT
)
VIN
Δ IL • f
VOUT • (1 -
In case RILIM is not connected, the IC uses an internal
default current-limit threshold.
Loop Compensation
The loop is compensated using a feedback network
around the error amplifier. Figure 22 shows a complete
type-3
compensation
network.
For
type-2
compensation, eliminate R3 and C3.
(4)
where f is the oscillator frequency.
Setting the Ramp Resistor Value
The internal ramp voltage excursion (ΔVRAMP) during tON
should be set to 0.6V at nominal operating point. RRAMP
is approximately:
RRAMP ( KΩ ) =
(VIN − 1.8) • VOUT
18 x10 − 6 • VIN • f
−2
(5)
where frequency (f) is expressed in KHz.
Figure 22. Compensation Network
Since the FAN2108 employs summing current-mode
architecture, type-2 compensation can be used for
many applications. For applications that require wide
loop bandwidth and/or use very low-ESR output
capacitors, type-3 compensation may be required.
Setting the Current Limit
There are two levels of current-limit thresholds in
FAN2108. The first level of protection is through an
internal default limit set at the factory to limit output
current beyond normal usage levels. The second level
of protection is externally settable at the ILIM pin.
Current-limit protection is enabled whenever the lower
of the two thresholds is reached. FAN2108 uses its
internal low-side MOSFET for current-sensing. The
current-limit threshold voltage (VILIM) is compared to a
scaled version of voltage drop across the low-side
MOSFET, sampled at the end of each PWM offtime/cycle. The internal default threshold (with ILIM open)
is temperature compensated.
Protection
The converter output is monitored and protected
against extreme overload, short-circuit, over-voltage,
under-voltage, and over-temperature conditions.
An internal fault latch is set for any fault intended to
shut down the IC. When the fault latch is set, the IC
discharges VOUT by enhancing the low-side MOSFET
until FB<0.25V. The MOSFET is not turned on again
unless FB>0.5V. This behavior discharges the output
without causing undershoot (negative output voltage).
The ILIM pin can source a 10µA current that can be
used to establish a lower, temperature–dependent,
current-limit threshold by connecting a resistor (RILIM)
between ILIM and AGND. RILIM can be approximated
with the equation:
RILIM(KΩ) = 95 + 3 • I out • KT • K1 +
Vout • 3.33 • 10
Rramp • fsw
Under-Voltage Shutdown
6
(6)
where:
I
= Desired current limit setpoint in Amps;
KT
= Normalized temperature coefficient of the
low-side MOSFET (Q2 from Figure 8);
K1
= Overload co-efficient (use 1.2 to 1.4);
VOUT = Set output voltage;
Rramp = Ramp resistor used in KΩ; and
fsw
= Selected switching frequency in KHz.
After 16 consecutive, pulse-by-pulse, current-limit
cycles, the fault latch is set and the regulator shuts
down. Cycling VCC or EN restores operation after a
normal soft-start cycle (refer to Auto-Restart section).
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
If voltage on the FB pin remains below the undervoltage threshold for 16 consecutive clock cycles, the
fault latch is set and the converter shuts down. This
protection is not active until the internal SS ramp
reaches 1.0V during soft-start.
Over-Voltage Protection / Shutdown
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
The over-current protection fault latch is active during
the soft-start cycle. Use a 1% resistor for RILIM.
Calculating the Inductor Value
If voltage on the FB pin exceeds the over-voltage
threshold for two consecutive clock cycles, the fault
latch is set and shutdown occurs.
A shorted high-side MOSFET condition is detected
when SW voltage exceeds ~0.7V while the low-side
MOSFET is fully enhanced. The fault latch is set
immediately upon detection.
The two fault protection circuits above are active all the
time, including during soft-start.
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11
Over-Temperature Protection (OTP)
After a fault, EN pin is discharged by a 1µA current sink
to a 1.1V threshold before the internal 800KΩ pull-up is
restored. A new soft-start cycle begins when EN
charges above 1.35V.
The chip incorporates an over-temperature protection
circuit that sets the fault latch when a die temperature of
about 150°C is reached. The IC restarts when the die
temperature falls below 125°C.
Depending on the external circuit, the FAN2108 can be
configured to remain latched-off or to automatically
restart after a fault.
Power-Good (PGOOD) Signal
PGOOD is an open-drain output that asserts LOW
when VOUT is out of regulation, as measured at the FB
pin. Thresholds are specified in the Electrical
Specifications section. PGOOD does not assert HIGH
until the fault latch is enabled (T1.0).
Table 1. Fault / Restart Configurations
EN Pin
Controller / Restart State
Pull to GND
Pull-up to VCC with
100K
Open
OFF (Disabled)
No Restart – Latched OFF(After
VCC Comes Up)
Immediate Restart After Fault
New Soft-Start Cycle After:
tDELAY (ms)=3.9 • C(nf)
Cap. to GND
PCB Layout
With EN is left open, restart is immediate.
If auto-restart is not desired, tie the EN pin to the VCC
pin or pull it HIGH after VCC comes up with a logic gate
to keep the 1µA current sink from discharging EN to
1.1V. Figure 23 shows one method to pull up EN to VCC
for a latch configuration.
15 VCC
100K
Figure 24. Recommended PCB Layout
FAN2108
14 EN
3.3n
Figure 23.
Enable Control with Latch Option
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
Auto-Restart
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2X
TOP VIEW
2X
RECOMMENDED LAND PATTERN
ALL VALUES TYPICAL EXCEPT WHERE NOTED
SIDE VIEW
SEATING
PLANE
A) DIMENSIONS ARE IN MILLIMETERS.
B) DIMENSIONS AND TOLERANCES PER
ASME Y14.5M, 1994
C) DIMENSIONS DO NOT INCLUDE MOLD
FLASH OR BURRS.
D) DESIGN BASED ON JEDEC MO-220
VARIATION WJHC
E) TERMINALS ARE SYMMETRICAL AROUND THE
X & Y AXIS EXCEPT WHERE DEPOPULATED.
F) DRAWING FILENAME: MKT-MLP25AREV2
BOTTOM VIEW
Figure 25. 5x6mm Molded Leadless Package (MLP)
Package drawings are provided as a service to customers considering Fairchild components. Drawings may change in any manner
without notice. Please note the revision and/or date on the drawing and contact a Fairchild Semiconductor representative to verify
or obtain the most recent revision. Package specifications do not expand the terms of Fairchild’s worldwide terms and conditions, specifically
the warranty therein, which covers Fairchild products.
FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
Physical Dimensions
Always visit Fairchild Semiconductor’s online packaging area for the most recent package drawings:
http://www.fairchildsemi.com/packaging/.
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
www.fairchildsemi.com
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FAN2108 — TinyBuck™, 3-24V Input, 8A, High-Efficiency, Integrated Synchronous Buck Regulator
14
www.fairchildsemi.com
© 2008 Fairchild Semiconductor Corporation
FAN2108 • Rev. 1.0.0
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