ASTEC APC18T12

Technical Reference Notes
APC18T12 Series
APC18T12 Series: 12Vin / 18A Non-Isolated Point-of-Load
The APC18 DC-DC Power Module is a high efficiency non-isolated buck converter designed for use in a wide variety of
applications. Packaged in an industry standard recognized SMT footprint: 1.3” x 0.53”, it works from a wide input voltage
range of 10V to 14V and offers a wide adjustable output range of 0.75V to 5.5V through external resistor programming.
Electrical Parameters
Input
Input Range
Input Surge
10-14VDC
15V / 100ms
Control
Enable
TTL compatible
(Positive or Negative Logic Enable Options)
Output
Special Features
•
•
•
•
•
•
•
•
Industry Standard SMT Footprint
High Efficiency up to 95% at 5V output
Adjustable output through external resistor
programming
Low output ripple and noise
Input UVLO
Fixed Switching Frequency
Positive Enable
Remote Sense pin
Load Current
Line/Load Regulation
Ripple and Noise
Output Voltage
Adjust Range
Transient Response
Remote Sense
Over Current
Protection
Over Voltage
Protection
Over Temperature
Protection
Up to 18A max (Po ≤ 75W)
< 1% VO
50mVP-P Typ
0.75 – 5.5VO
250mV Typ deviation
50% step
100µs settling time (Typ)
+10%VO
120% max
130% max
110 °C
Environmental Specifications
Safety
•
•
•
UL + cUL 60950, Recognized
EN60950 through TUV-PS
-40ºC to 85ºC Operating Temperature
-40ºC to 125ºC Storage Temperature
MTBF > 1 million hours
MODEL: APC18T12 SERIES
NOVEMBER 4, 2004 - REVISION 00
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Technical Reference Notes
APC18T12 Series
Electrical Specifications
ABSOLUTE MAXIMUM RATINGS
Stresses in excess of the absolute maximum ratings can cause permanent damage to the converter. Functional
operation of the device is converter is not implied at these or any other conditions in excess of those given in the
operational section of the specs. Exposure to absolute maximum ratings for extended period can adversely affect
device reliability.
Parameter
Input Voltage
Continuous
Transient (100ms)
Isolation Voltage
Input to Output
Operating Temperature
Storage Temperature
Operating Humidity
Max Voltage at Enable Pin
Max Output Power
Device
Symbol
Min
Typ
Max
Unit
All
VIN
VIN, trans
-
-
14
15
Vdc
NA
-40
-40
10
-
-
85
125
85
15
80
ºC
ºC
%
Vdc
W
Min
10.0
Typ
12.0
Max
14.0
Unit
Vdc
9.0
8.0
-
-
10.8
9.9
9.5
Vdc
2
0.5
W
All
All
All
All
All
Ta
TSTG
-
Device
All
Symbol
VIN
INPUT SPECIFICATION
Parameter
Operating Input Voltage Range
Input Under-Voltage Lock-out
T_ON Threshold
T_OFF Threshold
Input Current1
(VIN = VIN, Min; IO = IO, Max)
Max Pdiss @ IO = 0A
(VIN = VIN, Nom)
Input Ripple Current2
5Hz to 20MHz
MODEL: APC18T12 SERIES
NOVEMBER 4, 2004 - REVISION 00
All
All
5.50Vo
0.75Vo
All
IIN-MAX
II1
300
A
mAp-p
SHEET 2 OF 10
Technical Reference Notes
APC18T12 Series
Electrical Specifications (continued)
OUTPUT SPECIFICATIONS
Parameter
Output Voltage Set point
VIN = VIN, MIN to VIN,MAX;
IO =IO,Max
Output Regulation
Line: VIN = VIN, min to VIN, max
Device
Symbol
VO,SET
Min
0.735
Typ
0.75
Max
0.765
Unit
Vdc
All
-
-
-
0.5
Load: IO = IO, min to IO, max
All
-
-
15
30
Temp: TA = -40 ºC to +85ºC
Ripple and Noise4
Peak-to-Peak: (5Hz to 20MHz)
Output Current5
External Load Capacitance
Cap ESR = 1 mO
Cap ESR = 10 mO
Output Current-limit Inception6
All
All
-
-
50
0.5
75
%
%
mV
%
%
mVp-p
All
IO
0
-
18
A
1000
5000
µF
µF
Over Temperature Range6
All
All
All
IO
150%
95
-
120
°C
(AVG. PCB TEMP, measured at R11 location)
0.75V
1.20V
1.50V
1.80V
2.50V
3.30V
5.00V
η
η
η
η
η
η
η
76.0
83.0
85.5
87.0
89.5
91.5
93.5
78.0
84.5
87.0
88.5
91.0
92.5
94.5
-
%
%
%
%
%
%
%
All
-
-
3
6
ms
VIN = VIN-MIN to VIN-MAX
IO = IO,MIN to IO,MAX
Switching Frequency
All
-
-
-
8
ms
All
-
Output Turn-on Overshoot
Output Turn-off undershoot
(Passive Resistive Full Load)
Output Enable ON/OFF
Positive Enable*
Enable Pin Voltage: Mod-ON
Mod-OFF
All
-
-
-
5
-0.5
%Vo
V
All
-
2.6
0
-
15
0.8
V
V
Efficiency
VIN = VIN-NOM
IO = IO,MAX ; TA=25°C
Output voltage rise time
VIN = VIN-MIN to VIN-MAX
Enable to Output Turn-ON Delay
MODEL: APC18T12 SERIES
NOVEMBER 4, 2004 - REVISION 00
300
kHz
SHEET 3 OF 10
Technical Reference Notes
APC18T12 Series
Electrical Specifications (continued)
OUTPUT SPECIFICATIONS
Parameter
Dynamic Response8 (CO = 10uF
Tantalum + 1uF Ceramic)
Load Change of 50% step
anywhere between 10% to 100%
of rated load
Device
Symbol
∆IO/∆t
-
Peak Deviation
Settling Time to VO, Nom <5%
Peak deviation
Dynamic Response8 (CO = 150uF
x2 Special Polymer Aluminum
Capacitors)
Load Change of 50% step
anywhere between 10% to 100%
of rated load
All
-
Peak Deviation
Settling Time to VO, Nom <5%
Peak deviation
Output Voltage Trim Range9
Remote Sense
10
Min
Typ
Max
Unit
-
2.5
-
A/µs
-
250
100
300
150
mV
µs
∆IO/∆t
2.5
All
150
150
200
200
5.50
mV
µs
V
-
10%
V
All
All
0.75
A/µs
NOTE: 1. The converter is not internally fused. Recommended external fuse, Cooper Bussman 6125FA12A or
equivalent
2. External input capacitance required. See Figure 1.
4. Refer to Appendix A3 for the output ripple and Noise Test Measurement Setup.
5. Output current limited by 80W/Vo. Output Power Derating applies at elevated temperature. See Appendix
B for the Thermal Derating Curves.
6. OCP and OTP are in hiccup mode. The converter will auto restart without the need to recycle the input
voltage or toggle the enable signal and once the fault is removed. Vo higher than 1.5V, true OCP exists.
Vo less than 1.5V, OTP is used for OCP. Over current of not higher 150% for Vo less than 1.5V is
recommended. Typical overload condition is 150% or 27A. The module with Vo < 1.5V may not be
survival from over current exceeding 30A.
8. Load step response shall be measured at the load side of the output capacitors. See Appendix A4 for
the output and input cap requirement.
9. See appropriate Trim Equation and configuration in Appendix A6.
10. The combination of remote sense and output trim adjust cannot exceed 5.5V.
MODEL: APC18T12 SERIES
NOVEMBER 4, 2004 - REVISION 00
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Technical Reference Notes
APC18T12 Series
Electrical Specifications (continued)
SAFETY AGENCY / MATERIAL RATING / ISOLATION
Parameter
Safety Approval
Device
All
Material Flammability Rating
Input to Output Insulation Type
UL/cUL 60950, Flamability and Temperature Rise
All
All
UL94V-0
Non-Isolated
Figure 1. Measure input reflected-ripple current with a simulated source inductance L1
of 1 uH. Capacitor C1 offsets possible battery impedance. Measure current as shown
above.
COPPER STRIP
Vo(+)
C1
C2
C3
SCOPE
RESISTIVE
LOAD
Vo(-)
Figure 2. Use C1 = 0.1µF @50V X7R ceramic capacitor (connected an inch away
from the output terminals of the UUT), C2 = 10µF @ 25V tantalum capacitor (2 inches
away from the output terminals of the UUT), C3 = 2x 150uF Polymer cap. Scope
measurement should be made using a BNC socket, positioned 3 inches away from
output terminals of the converter.
MODEL: APC18T12 SERIES
NOVEMBER 4, 2004 - REVISION 00
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Technical Reference Notes
APC18T12 Series
Typical Application Circuit
Figure 3. Typical Application Circuit
Enable Pin
The converter comes with an Enable pin primarily used to turn ON/OFF the converter. The converter is disabled (OFF) when
the voltage across the Enable pin and ground is between 0V to 0.8V. The converter is Enabled (ON) when the voltage across
the Enable pin and ground is between 2.6V to 15V (or the Enable Pin is left open).
Output Trim
Output voltage adjustment is accomplished by connecting an external resistor between the Trim Pin and Ground Pin terminals.
Resistance and Output voltage relationship is established by Equation 1. If Trim pin is left open – default VO = 0.75V
TRIM-UP EQUATION:
Rtrim = ( V10500
− 1000)Ω
− 0.75
(1)
o
Where Rtrim is the resistance value in ohms and VO in Volts is the output voltage desired.
Table Rtrim values for different output voltage adjustment
Vo (V)
0.75
1.0
1.2
1.5
1.8
Rtrim (? ) from
open
41.0K
22.3K
13.0K
9.00K
Equation (1)
Rtrim (? ) from
open
41.2K
22.1K
13.0K
9.09K
E96
MODEL: APC18T12 SERIES
NOVEMBER 4, 2004 - REVISION 00
2.0
7.40K
2.5
5.00K
3.3
3.12K
5.0
1.47K
7.32K
4.99K
3.09K
1.47K
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Technical Reference Notes
APC18T12 Series
Performance Curves
Derating Curves
Figure 4. Output derating curve at VIN = 12V, VO =
5V.
Figure 5. Output derating curve at VIN = 12V, VO =
3.3V.
Figure 7. Output derating curve at VIN = 12V, VO =
1.8V.
Figure 7. Output derating curve at VIN = 12V, VO =
0.75V.
MODEL: APC18T12 SERIES
NOVEMBER 4, 2004 - REVISION 00
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Technical Reference Notes
APC18T12 Series
Mechanical Specifications
Parameter
Dimension
Device
All
AEO
Weight
AEO
Symbol
L
W
H
Min
-
Typ
-
Max
1.30 [33.02]
0.53 [13.46]
0.35 [8.89]
Unit
in [ mm ]
in [ mm ]
in [ mm ]
-
5 [0.16]
10 [0.32]
g [oz]
Figure 8. Mechanical Outline
PIN NAME
+VIN
Enable
GND
Sense
VO
Trim
DESIGNATION
+ Input Voltage
ON/OFF
Return for VIN and VO
+Output Sense pin
+Output
VO Adjust
Figure 9. PIN designation.
MODEL: APC18T12 SERIES
NOVEMBER 4, 2004 - REVISION 00
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Technical Reference Notes
APC18T12 Series
RECOMMENDED LOCATION FOR PICK AND PLACE
The flat top surface of the large inductor (topside of the board) provides a versatile and convenient way of picking up the
module (see Figure 10). A 6-7mm outside diameter nozzle from a conventional SMD machine is recommended to attain
maximum vacuum pick-up. Nozzle travel and rotation speed should be controlled to prevent this off-centered picked-up
module from falling off the nozzle. The use of vision recognition systems for placement accuracy will be very helpful.
RECOMMENDED REFLOW PROFILE
REFLOW NOTES / RECOMMENDATIONS
240
2.
3.
Refer to the recommended Reflow Profile per
Figure 11. Profile parameters exceeding the
recommended maximums may result to
permanent damage to the module.
The module is recommended for topside
reflow process to the host card. For other
orientations, contact factory.
In the event that the module needs to be
desoldered from the host card, some pins
may be detached from the module.
PEAK TEMPERATURE
200°C - 230°C
220
200
TEMPERATURE (deg C)
1.
183°C
180
REFLOW
ZONE
160
140
120
< 80 sec
110°C
PRE-HEAT ZONE
120 - 180 sec
100
80
SLOPE
< 4°C /sec
60
40
20
0
0
30
60
90
120
150
180
210
240
270
300
TIME (seconds)
Figure 10. Recommended Reflow profile.
PICK-UP LOCATION
Figure 11. Recommended Pick-up location.
MODEL: APC18T12 SERIES
NOVEMBER 4, 2004 - REVISION 00
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Technical Reference Notes
APC18T12 Series
TABLE 2: PART NUMBERING SCHEME
APC
O/P CURRENT
O/P VOLTAGE
I/P Voltage
xx
y
12
18 = 18A
T = 0.75V
12 = 10V – 14V
OPTIONS
-
9
z
J = Tray packaging
Non “J” = T&R packaging
Please call 1-888-41-ASTEC for further inquiries
or visit us at www.astecpower.com
MODEL: APC18T12 SERIES
NOVEMBER 4, 2004 - REVISION 00
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