Datasheet

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rev.
PART NUMBER: VPOL5A-12-SMT
page
1 of 12
date
08/2007
DESCRIPTION: point of load converter
features
* industry standard pin out
* high efficiency to 92%
* 300 KHz switching frequency
* 8.3-14 VDC wide input range
* 0.75-5.0 VDC wide output range
* over temperature protection
* continuous short circuit protection
* remote on/off
* cost-efficient open frame design
* UL/C-UL60950-1 (E222736) certified
* RoHS compliant
1. INTRODUCTION
2. VPOL5A-12-SMT CONVERTER FEATURES
7. APPLICATIONS
7.1 Layout Design Challenges.
3. GENERAL DESCRIPTION
3.1 Electrical Description
7.2 Convection Requirements for Cooling
3.2 Thermal Packaging and Physical Design.
7.4 Power De-Rating Curves
4. TECHNICAL SPECIFICATIONS
7.5 Efficiency vs Load Curves
5. MAIN FEATURES AND FUNCTIONS
5.1 Operating Temperature Range
7.6 Input Capacitance at the Power Module
5.2 Over-Temperature Protection (OTP)
7.8 VPOL5A-12-SMT Output Voltage Adustment.
5.3 Output Voltage Adjustment
7.9 Output Ripple and Noise Measurement
5.4 Safe Operating Area (SOA)
7.10 Output Capacitance
5.5 Over Current Protection
7.11 VPOL5A-12-SMT Reflow Profile
5.6 Remote ON/OFF
5.7 UVLO (Under-Voltage Lockout)
6. SAFETY
6.1 Input Fusing and Safety Considerations.
7.3 Thermal Considerations
7.7 Test Set-Up
8. MECHANICAL OUTLINE DIAGRAMS
8.1 VPOL5A-12-SMT Mechanical Outline Diagrams
8.2 VPOL5A-12-SMT Tape and Reel Dimensions
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2382
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rev.
PART NUMBER: VPOL5A-12-SMT
page
2 of 12
date
08/2007
DESCRIPTION: point of load converter
If the converter is overloaded or the ambient temperature gets too
1. Introduction
high, the converter will shut down to protect the unit.
L1
Q1
This application note describes the features and functions of #5)).#gS
+VIN
+VO
VPOL5A-12-SMT series of non-isolated dc-dc converters. These are
highly efficient, reliable and compact, high power density, single output
Q2
C1
D1
C2
DC/DC converters. These “Point of Load” modules serve the needs
specifically of the fixed and mobile telecommunications and computing
market, employing economical distributed Power Architectures. The
VPOL5A-12-SMT series provide precisely regulated output voltage
COM
COM
range from 0.75V to 5.0Vdc over a wide range of input voltage (Vi=8.3 –
R1
PWM IC
14Vdc) and can operate over an ambient temperature range of –40°C
ON/OFF
R trim
ERR AMP
to +85°C. Ultra-high efficiency operation is achieved through the use of
TRIM
R2
synchronous rectification and drive control techniques.
The modules are fully protected against short circuit and overtemperature conditions. #5)).#gS world class automated
Figure 1. Electrical Block Diagram
manufacturing methods, together with an extensive testing and
qualification program, ensure that all VPOL5A-12-SMT series
3.2 Thermal Packaging and Physical Design.
converters are extremely reliable.
The VPOL5A-12-SMT series uses a multi-layer FR4 PCB construction.
All surface mount power components are placed on one side of the
PCB, and all low-power control components are placed on the other
2.VPOL5A-12-SMT Converter Features
side. Thus, the heat dissipation of the power components is optimized,
ensuring that control components are not thermally stressed. The
High efficiency topology, typically 89% at 3.3Vdc
Industry standard footprint
Wide ambient temperature range, -40°C to +85°C
converter is an open-frame product and has no case or case pin. The
open-frame design has several advantages over encapsulated closed
devices. Among these advantages are:
Cost efficient open frame design
Programmable output voltage via external resistor from 0.75 to
Efficient Thermal Management: the heat is removed from the
5.0Vdc
heat generating components without heating more sensitive, small
No minimum load requirement (Stable at all loads)
signal control components.
Remote ON/OFF
Environmental: Lead free open-frame converters are more easily
Fixed switching frequency
re-cycled.
Continuous short-circuit protection and over current protection
Cost Efficient: No encapsulation. Cost efficient open-frame
Over-temperature protection (OTP)
construction.
Monotonic Startup with pre-bias at the output.
Reliable: Efficient cooling provided by open frame construction
UL/IEC/EN60950 Certified.
offers high reliability and easy diagnostics.
3. General Description
3.1 Electrical Description
A block diagram of the VPOL5A-12-SMT series converter is shown in
Figure 1. Extremely high efficiency power conversion is achieved
through the use of synchronous rectification and drive techniques.
Essentially, the powerful VPOL5A-12-SMT series topology is based on
a non-isolated synchronous buck converter. The control loop is
optimized for unconditional stability, fast transient response and a very
tight line and load regulation. In a typical pre-bias application the
VPOL5A-12-SMT series converters do not draw any reverse current at
start-up. The output voltage can be adjusted from 0.75 to 5.0vdc, using
the TRIM pin with a external resistor. The converter can be shut down
via a remote ON/OFF input that is referenced to ground. This input is
compatible with popular logic devices; a 'positive' logic input is supplied
as standard. Positive logic implies that the converter is enabled if the
remote ON/OFF input is high (or floating), and disabled if it is low. The
converter is also protected against over-temperature conditions.
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2382
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rev.
page
3 of 12
date
08/2007
DESCRIPTION: point of load converter
PART NUMBER: VPOL5A-12-SMT
4. Technical Specifications
(All specifications are typical at nominal input, full load at 25°C unless otherwise noted.)
PARAMETER
ABSOLUTE MAXIMUM RATINGS
Input Voltage
Continuous
Operating Temp erature
See Thermal Considerations Section
NOTES and CONDITIONS
Device
Min.
Typical Max.
Units
ALL
0
15
Vdc
ALL
-40
+85
°C
ALL
-55
+125
°C
ALL
8.3
14
Vdc
Storage Temperature
INPUT CHARACTERISTICS
Operating Input Voltage
Input Under-Voltage Lockout
Turn-On Voltage Threshold
Turn-Off Voltage Threshold
Lockout Hysteresis Voltage
12
Vdc
Vdc
Vdc
8.0
7.9
0.1
ALL
ALL
ALL
ALL
3.5
A
Maximum Input Current
Vin=0 to 14Vdc , Io=Io,max.
No-Load Input Current
Vo=0.75V
Vo=1.2V
Vo=1.5V
Vo=1.8V
Vo=2.0V
Vo=2.5V
Vo=3.3V
Vo=5.0V
ALL
Off Converter Input Current
Shutdown input idle current
ALL
10
mA
ALL
0.1
As
2
Inrush Current (I t)
Input Reflected-Ripple Current
20
25
25
30
30
35
45
50
mA
2
P-P thru 1uH inductor, 5Hz to 20MHz
ALL
150
mA
Output Voltage Set Point
Vin=Nominal Vin , Io=Io.max, Tc=25
ALL
-1.5% Vo,set +1.5%
Vdc
Output Voltage Trim Adjustment Range
Selected by an external resistor
ALL
0.7525
5.0
Vdc
Io=Io.min to Io.max
ALL
-0.5
+0.5
%
OUTPUT CHARACTERISTIC
Output Voltage Regulation
Load Regulation
Vin=low line to high line
ALL
-0.2
+0.2
%
Tempera ture Coefficient
Line Regulation
Ta=-40°C to 85°C
ALL
-0.03
+0.03
%/°C
Output Voltage Ripple and Noise
5Hz to 20MHz bandwidth
Other Voltages
Vo=5V
Other Voltages
Vo=5V
50
75
20
45
Low ESR
ALL
3000
ALL
0
Output DC Current-Limit Inception
Output Voltage =90% Nominal Output Voltage
ALL
6
Shout Circuit Protection
Continuous with Hiccup Mode
Peak-to-Peak
RMS
External Capacitive Load
Full Load, 1uF ceramic and 10uF tantalum
Full Load, 1uF ceramic and 10uF tantalum
Operating Output Current Range
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2382
8.5
mV
mV
uF
5
A
11
A
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rev.
4 of 12
date
08/2007
DESCRIPTION: point of load converter
PART NUMBER: VPOL5A-12-SMT
PARAMETER
DYNAMIC CHARACTERISTICS
page
NOTES and CONDITIONS
Device
Min.
Typical Max.
Units
Output Voltage Transient Response
Error Brand
50% Step Load Change, di/dt=0.1A/us
ALL
200
mV
Setting Time (within 1% Vout nominal)
50% Step Load Change, di/dt=0.1A/us
ALL
200
us
EFFICIENCY
100% Load
Vo=0.75V
Vo=1.2V
Vo=1.5V
Vo=1.8V
Vo=2.0V
Vo=2.5V
Vo=3.3V
Vo=5.0V
ALL
Non-isolation
ALL
73
80
82
84
85
87
89
92
%
ISOLATION CHARACTERISTICS
Input to Output
0
Vdc
FEATURE CHARACTERISTICS
Switching Frequency
ON/OFF Control, Positive Logic Remote On/Off
Logic Low (Module Off)
Logic High (Module On)
ALL
Standard Model
0
or Open Circuit
ON/OFF Control, Negative Logic Remote On/Off
Logic Low (Module On)
or Open Circuit
Logic High (Module Off)
ON/OFF Current (for both remote on/off logic)
Leakage Current (for both remote on/off logic)
Turn-On Delay and Rise Time
Turn-On Delay Time, From On/Off Control
Turn-On Delay Time, From Input
Output Voltage Rise Time
Over Temperature Protection
300
KHz
0.4
Vdc
Vdc
0.4
Vin
Vdc
Vdc
1
1
mA
mA
Vin
Suffix “N” Model
0
2.8
Ion/off at Von/off =0.0V
Logic High, Von/off=14V
ALL
AL L
Von/off to 10 %Vo,set
Vin,min. to 10%V o,set
10%Vo,set to 90 %Vo,set
ALL
ALL
ALL
ALL
3.5
3.5
3.5
120
ms
ms
ms
°C
ALL
1.5
M hours
ALL
2.3
grams
GENERAL SPECIFICATIONS
MTBF
Weight
Dimensions
SMT packages
Io=100%of Io.max;Ta=2 5°C per MIL-HDBK217F
0.8x0.45x0.24 inches(20.3x11.43x6.09 mm)
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2382
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rev.
PART NUMBER: VPOL5A-12-SMT
page
5 of 12
date
08/2007
DESCRIPTION: point of load converter
5. Main Features and Functions
5.4 Safe Operating Area (SOA)
5.1 Operating Temperature Range
(SOA) of the converter. This representation assumes ambient
#5)).#gS VPOL5A-12-SMT series converters highly efficient converter
operating conditions such as airflow are met as per thermal guidelines
design has resulted in its ability to operate over a wide ambient
provided in Sections 7.2 and 7.3.
Figure 2 provides a graphical representation of the Safe Operating Area
temperature environment ( -40°C to 85°C). Due consideration must be
given to the de-rating curves when ascertaining maximum power that
Vo
can be drawn from the converter. The maximum power drawn is
influenced by a number of factors, such as:
Input voltage range.
Air velocity (forced or natural convection).
Mounting orientation of converter PCB with respect to the Airflow.
Motherboard PCB design, especially ground and power planes.
These can be effective heat sinks for the converter.
Vo,nom
VOLTAGE (V)
Output load current.
Safe Operating Area
5.2 Over-Temperature Protection (OTP)
Io,max Io,CL Io
The VPOL5A-12-SMT series converters are equipped with non-latching
CURRENT (A)
over-temperature protection. A te mperature sensor monitors the
temperature of the hot spot (typically, top switch). If the temperature
Figure 2. Maximum Output Current Safe Operating Area
exceeds a threshold of 120°C (t ypical) the converter will shut down,
disabling the output. When the temperature has decreased the
converter will automatically restart.
5.5 Over Current Protection
The over-temperature condition can be induced by a variety of reasons
All different voltage models have a full continuous short-circuit
such as external overload condition or a system fan failure.
protection. The unit will auto recover once the short circuit is removed.
To provide pr otection in a fault condition, the unit is equipped with
internal over-current protection. The unit operates normally once the
5.3 Output Voltage Adjustment
fault condition is removed. The power module will supply up to 150% of
Section 7.8 describes in detail as to how to trim the output voltage with
rated current. In the event of an over current converter will go into a
respect to its set point. The output voltage on all models is trimmable in
hiccup mode protection.
the range 0.75 – 5.0Vdc.
5.6 Remote ON/OFF
The remote ON/OFF input feature of the converter allows external
circuitry to turn the converter ON or OFF. Active-high remote ON/OFF
is available as standard. The VPOL5A-12-SMT series converters are
turned on if the remote ON/OFF pin is high, or left open or floating.
Setting the pin low will turn the converter ‘Off’. The signal level of the
remote on/off input is defined with respect to ground. If not using the
remote on/off pin, leave the pin open (module will be on). The part
number suffix “N” is Negative remote ON/OFF version. The unit is
guaranteed OFF over the full temperature range if this voltage level
exceeds 2.8Vdc. The converters are turned on If the on/off pin input is
low or left open. The recommended remote on/off drive circuit as shown
as figure 3, 4.
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2382
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rev.
6 of 12
date
08/2007
DESCRIPTION: point of load converter
PART NUMBER: VPOL5A-12-SMT
+Vin
ON/OFF
Control
page
+Vo
Remote ON/OFF
7. Applications
7.1 Layout Design Challenges.
Q1
In optimizing thermal design the PCB is utilized as a heat sink. Also
VPOL5A-12-SMT
some heat is transferred from the VPOL5A-12-SMT module to the main
board through connecting pins. The system designer or the end user
Common
Common
must ensure that other components and metal in the vicinity of the
VPOL5A-12-SMT series meet the spacing requirements to which the
Figure 3. Positive Remote ON/OFF Input Drive Circuit
system is approved.
Low resistance and low inductance PCB layout traces are the norm and
+Vin
+Vo
Q1
to proper low impedance tracks between power module, input and
output grounds. The recommended VPOL5A-12-SMT footprint as
VPOL5A-12-SMT
ON/OFF
Control
should be used where possible. Due consideration must also be given
Remote ON/OFF
shown as figure 5.
Recommended Pad Layout
Dimensions are in Inches ( millimetes )
Common
Common
0.180
(4.57)
0.160
(4.06)
0.160
(4.06)
0.190
(4.83)
Figure 4. Negative Remote ON/OFF Input Drive Circuit
VOUT
5.7 UVLO (Under-Voltage Lockout)
The voltage on the Vcc pin determines the start of the operation of the
TRIM
GND
0.340
(8.64)
0.350
(8.89)
Converter. When the input Vcc rises and exceeds about 8.0V the
ON/OFF
converter initiates a soft start. The UVLO function in the converter has a
0.010
(0.25)
VIN
hysteresis (about 100mV) built in to provide noise immunity at start-up.
0.06
(1.5)
6. Safety
6.1 Input Fusing and Safety Considerations.
0.05
(1.3)
0.690
(17.53)
PAD SIZE
MIN : 0.120" x 0.095 "
MAX : 0.135" x 0.110 "
Figure 5. Recommended VPOL5A-12-SMT Footprint (Top View)
Agency Approvals: The power supply shall be submitted to and
receive formal approval from the following test agencies.
1.The power supply shall be approved by a nationally recognized
rd
testing laboratory to UL/CSA 60950 3 Edition (North America) and
EN60950 (International)
2. CB Certificate from an internationally recognized test house in
accordance with EN 60950.
The VPOL5A-12-SMT series converters do not have an internal fuse.
However, to achieve maximum safety and system protection, always
use an input line fuse. The safety agencies require a time-delay fuse
with a maximum rating of 7A.
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2382
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rev.
page
7 of 12
date
08/2007
DESCRIPTION: point of load converter
PART NUMBER: VPOL5A-12-SMT
7.2 Convection Requirements for Cooling
To predict the ap proximate cooling needed for the module, refer to the
Power De-rating curves in Figures 10 to 13. These de-rating curves are
approximations of the ambient temperatures and airflows required to
keep the power module temperature below its maximum rating. Once
the module is assembled in the actual system, the module’s
temperature should be checked as shown in Figure 6 to ensure it does
not exceed 110°C.
Proper cooling can be verified by measuring the power module’s
temperature at Q1-pin 6 as shown in Figure 7.
W ind
Tunnel
Figure 7. Temperature Measurement Locati on for
VPOL5A-12-SMT
25.4(1.0)
7.3 Thermal Considerations
Bakelite
Power Module
76.2(3.0)
Thermocuple Location
for measuring
ambient temperature
and airflow
The power module operates in a variety of thermal environments;
however, sufficient cooling should be provided to help ensure reliable
operation of the unit. Heat is removed by conduction, convection, and
radiation to the surrounding environment. The thermal data presented is
based on measurements taken in a set-up as shown in Figure 7.
Figures 8 & 9 represent the test data. Note that the airflow is parallel to
the long axis of the module as shown in Figure 6 for the VPOL5A-12SMT.
The temperature at either location should not exceed 110 °C. The
output power of the module should not exceed the rated power for the
module (VO, set x IO, max). The VPOL5A-12-SMT thermal data
presented is based on measurements taken in a wind tunnel. The test
setup shown in Figure 6 and EUT need to solder on 33mm x
40.38mm(1.300'' x 1.59'') test pcb. Note that airflow is parallel to the
long axis of the module as shown in Fig 7.
12.7(0.5)
Air
flow
Note : Dimensions are in millimeters and (inches)
Figure 6. Thermal Test Setup
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2382
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rev.
DESCRIPTION: point of load converter
PART NUMBER: VPOL5A-12-SMT
TYPICAL POWER DERATING FOR 5 Vin 3.3 Vout
6.0
Output Current(A)
5.0
4.0
0LFM
3.0
100LFM
2.0
200LFM
1.0
0.0
0
10
20
30
40
50
60
70
80
90
100
o
Ambient Temperature( C)
Figure 3. Typi
cal Power De-rating for12V IN 3.3V
out
NOTE:
1. specific input & output derating curves available, please
contact #5)).# for detail
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2382
page
8 of 12
date
08/2007
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rev.
page
9 of 12
date
08/2007
DESCRIPTION: point of load converter
PART NUMBER: VPOL5A-12-SMT
VPOL5A-12-SMT Vo=1.8V (Eff Vs Io)
VPOL5A-12-SMT Vo=1.5V (Eff Vs Io)
100%
100%
95%
95%
Efficincy (%)
Efficincy (%)
90%
90%
85%
8.3V
12V
14V
80%
75%
85%
80%
75%
8.3V
12V
14V
70%
65%
70%
60%
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
0
5
0.5
1
Current Load (A)
2
2.5
3
3.5
4
4.5
5
Current Load (A)
VPOL5A-12-SMT Vo=1.2V (Eff Vs Io)
VPOL5A-12-SMT Vo=0.75V (Eff Vs Io)
90%
95%
85%
90%
80%
Efficincy (%)
100%
Efficincy (%)
1.5
85%
80%
75%
8.3V
12V
14V
70%
65%
75%
70%
65%
8.3V
12V
14V
60%
55%
60%
50%
0
0.5
1
1.5
2
2.5
3
Current Load (A)
3.5
4
4.5
5
0
0.5
1
1.5
2
2.5
3
Current Load (A)
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2382
3.5
4
4.5
5
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rev.
page
10 of 12
date
08/2007
DESCRIPTION: point of load converter
PART NUMBER: VPOL5A-12-SMT
Where:
VFL is the output voltage at full load
VNL is the output voltage at no load
7.6 Input Capacitance at the Power Module
The VPOL5A-12-SMT converters must be connected to a low AC
source impedance. To avoid probl ems with loop stability source
inductance should be low. Also, the input capacitors should be placed
close to the converter input pins to de-couple distribution inductance.
However, the external input capacitors are chosen for suitable ripple
handling capability. Low ESR polymers are a good choice. They have
high capacitance, high ripple rating and low ESR (typical <100mohm).
Electrolytic capacitors should be avoided. Circuit as shown in Figure 10
represents typical measurement methods for ripple current. Input
reflected-ripple current is measured with a simulated source Inductance
of 1uH. Current is measured at the input of the module.
The value of line regulation is defined as:
Line.reg =
VHL _ VLL
x 100%
VLL
Where: VHL is the output voltage of maximum input voltage at full load.
VLL is the output voltage of minimum input voltage at full load.
Current Meter
A
Power
Supply
+Vin
+
47uF
10UF
V
VPOL5A-12-SMT
CERAMIC
Common
To Oscilloscope
Figure 11. VPOL5A-12-SMT Test Setup
+Vin
1uH
Power
+
2*100uF
Tantalum
Supply
VPOL5A-12-SMT
220uF
ESR<0.1ohm
Common
Figure 10. Input Reflected-Ripple Test Setup
7.7 Test Set-Up
The basic test set-up to measure parameters such as efficiency and
load regulation is shown in Figure 11. Things to note are that this
converter is non-isolated, as such the input and output share a common
ground. These grounds should be connected together via low
impedance ground plane in the application circuit. When testing a
converter on a bench set-up, ensure that -Vin and -Vo are connected
together via a low impedance short to ensure proper efficiency and load
regulation measurements are being made. When testing the #5)).#gS
VPOL5A-12-SMT under any transient conditions please ensure that the
transient response of the source is sufficient to power the equipment
under test. We can calculate the
Efficiency
Load regulation and line regulation.
The value of efficiency is defined as:
ç=
Vo x Io
x100%
Vin x Iin
Where:
Vo is output voltage,
Io is output current,
Vin is input voltage,
Iin is input current.
The value of load regulation is defined as:
Load .reg=
Common
Voltage Meter
L1
A
+Vo
+Sense
VFL _ VNL
x 100%
VNL
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V
Load
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rev.
page
11 of 12
date
08/2007
DESCRIPTION: point of load converter
PART NUMBER: VPOL5A-12-SMT
7.8 VPOL5A-12-SMT Output Voltage Adustment.
7.9 Output Ripple and Noise Measurement
The output Voltage of the VPOL5A-12-SMT can be adjusted in the
range 0.75V to 5.0V by connecting a single resistor on the motherboard
(shown as R trim) in Figure 12. When Trim resistor is not connected the
output voltage defaults to 0.75V
The test set-up for noise and ripple measurements is shown in Figure
13. a coaxial cable with a 50ohm termination was used to prevent
impedance mismatch reflections disturbing the noise readings at higher
frequencies.
+Vin
+Vin
+Vo
+Vo
Common
Common
Common
Figure 13. Output Voltage Ripple and Noise Measurement Set-Up
Figure 12. Trim-up Voltage Setup
The value of Rtrim-up defined as:
10500 _
1000 )
_
Vo
.750
Rtrim-up is the external resistor in ohm,
Vo is the desired output voltage
To give an exa mple of the above calculation, to set a voltage of 3.3Vdc,
Rtrim is given by:
Where:
Rtrim = (
R-Load
Test Jack
R trim-up
Rtrim = (
1uF
Ceramic
R-Load
VPOL5A-12-SMT
Common
10uF
Tant.
VPOL5A-12-SMT
Trim
10500 _
1000 )
_
3 . .75
30
Rtrim = 3118 ohm
For various output values various resistors are calculated and provided
in Table 3 for co nvenience.
7.10 Output Capacitance
#5)).#gS VPOL5A-12-SMT converters provide unconditional stability
with or without external capacitors. For good transient response low
ESR output capacitors should be located close to the point of load.
For high current applications point has already been made in layout
considerations for low resistance and low inductance tracks.
Output capacitors with its associated ESR values have an impact on
loop stability and bandwidth. #5)).#gSconverters are designed to
work with load capacitance up-to 3,000uF. It is reco mmended that any
additional capacitance, Maximum 3,000uF and low ESR, be connected
close to the point of load and outside the remote compensation point.
7.11 VPOL5A-12-SMT Reflow Profile
An example of the reflow profile is given in Figure 14.
Equipment used: SMD HOT AIR REFLOW HD-350SAR
Alloy: AMQ-M293TA or N C-SMQ92 IND-82088 SN63
REFLOW PROFILE
Rtrim (Kohm)
Open
22.33
13.00
9.00
7.40
5.00
3.12
1.47
Table 3 – Trim Resistor Values
240
200
TEMPERATURE (C)
Vo,set (V)
0.75
1.2
1.5
1.8
2.0
2.5
3.3
5.0
160
120
80
40
0
0
30
60
90
120 150 180 210 240
TIME (SECONDS)
Figure 14
VPOL5A-12-SMT Reflow Profile
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2382
For more information, please visit the product page.
rev.
page
12 of 12
date
08/2007
DESCRIPTION: point of load converter
PART NUMBER: VPOL5A-12-SMT
8. Mechanical Outline Diagrams
8.2 VPOL5A-12-SMT Tape and Reel Dimensions
8.1 VPOL5A-12-SMT Mechanical Outline Diagrams
Dimensions are in millimeters and inches
Tolerance: x.xx ±0.02 in. (0.5mm) , x.xxx ±0.010 in. (0.25 mm) unless
otherwise noted
The Ta pe Reel dimensions for the VPOL5A-12-SMT module is shown
in Figure 16.
t
BOTTOM VIEW OF BOARD
0.80
(20.3)
0.190
(4.83)
0.160
(4.06)
GND
0.35
(8.9)
0.160
(4.06)
TRIM
0.24
(6.09) max.
0.180
(4.06)
VOUT
0.065
(1.65)
0.340
(8.64)
0.450
(11.43)
VIN
0.062
(1.57)
ON/OFF
0.06 (1.5)
Surface Mount Contact 5 Places
0.090
0.05 (1.3)
(2.29)
Dimensions are in Inches (millimeters)
Tolerances :x.xx ¡ Ó0.02in.( x.x ¡ Ó0.5mm) , unless otherwise noted
x.xxx ¡ Ó0.010in. ( x.xx ¡ Ó0.25mm)
Figure 15 VPOL5A-12-SMT Mechanical Outline Diagram
W
Ao
Bo
Ko
P
F
E
D
D1
Po
P2
t
Figure 16 – VPOL5A-12-SMT Tape a nd Reel Dimensions
20050 SW 112th Ave. Tualatin, Oregon 97062 phone 503.612.2300 fax 503.612.2382