ASTEC AEH60F48

Technical Reference Notes
Hercules (AEH/ALH60) Open
Frame or HS Adapted
AEH60F48 /ALH60F48 Isolated DC/DC Converter Module
Industry Standard ½ Brick – 36-75V Input, 3.3V / 60A Output
The AEH60F48 / ALH60F48 is part of Astec’s New Ultra High Density ½ Brick family capable of running 60Amps at 3.3V
output. With Efficiencies up to 92% typical at 3.3V - 60Amps, this product provides a 1% to 2% performance increase in
efficiency over the leading 60Amp competitors and up to 10% higher output current. The operating temperature range (40°C to 85°C for the ALH; -40°C to 100°C baseplate for AEH) assures maximum application flexibility. New singleoutput models feature superior transient response with excellent stability in high capacitance/low ESR load applications.
This family has an effective thermal adapter plate which allows for heat sinking under particularly harsh conditions.
Without the adapter plate (ALH60) provides a very effective low profile which performs extremely well in convection
cooled applications.
Electrical Parameters
Input
Input range
Input Surge
Efficiency
36-75 VDC
100V / 100ms
[email protected] (Typical @ 60
Amps)
Control
Enable
TTL compatible
(Positive & Negative enable options)
Industry Standard
½ Brick Package
Special Features
Output
Regulation
(Line, Load, Temp)
Ripple and Noise
•
•
•
•
•
•
•
•
•
High efficiency, 92% (30-70%Load))
-40°C to 100°C baseplate operating temp
Open Frame version also available
(ALH60)
Positive and Negative enable function
Low output ripple and noise
High capacitive load limit
Remote sense compensation
Regulation to zero load
Fixed frequency switching (190 KHz)
<2%
Remote Sense
2% typical (100mV p-p
max)
Up to 10%Vout
Output Voltage
Adjust Range
±10% of nominal output
Transient Response
Over Voltage
Protection
150mV max deviation with
50% to 75% full load
300 µS (max) recovery
130% nominal
Environmental Specifications
•
•
•
Operating temperature:
-40°C to +85°C for Open Frame (ALH60)
-40°C to +100°C (Baseplate) for (AEH60)
Storage temperature: -40°C to +125C
MTBF: >1 million hours
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
Safety
§
§
UL, cUL 60950 Recognized
EN 60950 through TUV-PS
SHEET 1 OF 21
Technical Reference Notes (AEH60/ALH60F48)
AEH60 / ALH60 SERIES
THIS SPECIFICATION COVERS THE REQUIREMENTS
FOR AN INDUSTRY STANDARD HALF BRICK (MAX 198W @ 3.3V) SINGLE OUTPUT ULTRA HIGH
EFFICIENCY ISOLATED DCDC CONVERTER
MODEL NAME / SIS CODE
AEH60F48
AEH60G48
AEH60Y48
AEH60K48
ALH60F48
ALH60G48
ALH60Y48
ALH60K48
Construction
HS Adapter
HS Adapter
HS Adapter
HS Adapter
Open Frame 0.4”
Open Frame 0.4”
Open Frame 0.4”
Open Frame 0.4”
Vout, Iout
3.3V/60A
2.5V/60A
1.8V/60A
1.2V/60A
3.3V/60A
2.5V/60A
1.8V/60A
1.2V/60A
Options:
Negative Enable:
Positive Enable:
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
Suffix
"N"
no suffix
SHEET 2 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Electrical Specifications
STANDARD TEST CONDITION on a single unit, unless otherwise specified.
TA:
+VIN:
-VIN:
Enable:
+VOUT:
-VOUT:
Trim (VADJ):
+Sense:
-Sense:
25°C (Ambient Air)
48V ± 2%
Return pin for +VIN
Open (Positive Enable)
Connect to Load
Connect to Load (return)
Open
Connect to +VOUT
Connect to -VOUT
ABSOLUTE MAXIMUM RATINGS
Stresses in excess of the absolute maximum ratings can cause permanent damage to the device. Functional
operation of the device is not implied at these or any other conditions in excess of those given in the operational
sections of the specs. Exposure to absolute maximum ratings for extended periods can adversely affect device
reliability.
Parameter
Input Voltage:
Continuous:
Transient (100ms)
Device
Symbol
Min
Typ
Max
Unit
All
All
VI
VI, trans
0
0
-
75
100
Vdc
Vdc
Operating Temperature
AEH
ALH
TC
TA
-40
-40
-
100
85
ºC
°C
Storage Temperature
All
TSTG
-55
-
125
ºC
Operating Humidity
All
-
-
-
85
%
All
AEH
AEH
-
-
-
1500
1500
1500
Vdc
Vdc
Vdc
3.3V
PO,max
-
-
198
W
I/O Isolation
(Conditions : 50µA for 5 sec,
slew rate of 1500V/10sec)
Input-Output
Input-Case
Output-Case
Output Power
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 3 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Electrical Specifications (continued)
INPUT SPECIFICATIONS
Parameter
Operating Input Voltage
Device
All
Symbol
VIN
Min
36
Typ
48
Max
75
Unit
VDC
Maximum Input Current1
(VIN = 0 to VIN,max: IO = IO,max)
F (3.3V)
IIN,max
-
-
7.2
A
Input Reflected-ripple Current 2
(5Hz to 20MHz: 12uH source
impedance: TA = 25 ºC.)
All
II
-
-
15
mAPK-PK
No Load Input Power
(VIN = VIN,nom )
All
-
-
-
5
W
Note:
1. The power module is not internally fused. An input line fuse must always be used.
2. See Figure 1 for the Input Reflected-Ripple Current Test Setup.
OUTPUT SPECIFICATIONS
Parameter
Output Voltage Setpoint
(VIN = VIN,min to VIN,max at
IO = IO,max ; TA = 25 ºC )
Device
3.3V
Symbol
VO,SET
Min
3.24
Typ
3.3
Max
3.34
Unit
Vdc
All
All
All
-
-
0.1
0.1
-
0.4
0.4
1.0
%
%
%Vo
3.3V
-
-
66
-
100
150
mVPK-PK
mVPK-PK
External Load Capacitance
(See Stability Curves for Detail)
All
-
-
-
50,000
µF
Rated Output Current
All
Io
0
-
60
A
Output Current-limit Inception
(when unit is shut down)
All
Io
63
-
77
A
3.3V
-
90
91
-
%
All
-
180
195
210
KHz
Output Regulation:
Line
Load (IO = IO,min to IO,max)
Temp (AEH: -40 ºC to 100ºC)
(ALH: -40°C to 85°C)
Output Ripple and Noise3
Peak-to-Peak (5 Hz to 20 MHz)
VIN = 36V, 48V
VIN = 75V
Efficiency4
(VI = VIN,nom ; IO,max ; TA = 25°C)
Switching Frequency
Note:
3. See Figure 2 for the Output Ripple Test Setup
4. Refer to Figures 5 and 6 for the Efficiency Curves
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 4 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Electrical Specifications (continued)
OUTPUT SPECIFICATIONS
Parameter
Dynamic Response5 :
(∆IO/∆t = 1A/10µs ; VI = VIN,nom ;
TA = 25°C)
Device
Symbol
Min
Typ
Max
Unit
Load Change from IO = 50% to
75% of IO,max :
Peak Deviation Settling Time (to
VO,nom)
All
-
-
-
150
mV
-
-
-
300
µsec
Load Change from IO = 50% to
25% of IO,max :
Peak Deviation Settling Time (to
VO,nom)
All
-
-
-
150
mV
-
-
-
300
µsec
All
-
-
4
10
msec
All
-
-
0
4
%Vo
Turn-On Time
(IO = IO,max ; Vo within 1%)
Output Voltage Overshoot
(IO = IO,max ; TA = 25°C)
Note:
5. Refer to the Transient characteristics on Figures 7 and 8.
FEATURE SPECIFICATIONS
Parameter
Enable Pin Voltage :
Logic Low
Logic High
Enable Pin Current :
Logic Low
Logic High (ILEAKAGE at 10V)
Device
Symbol
Min
Typ
Max
Unit
All
All
-0.7
2.95
-
1.2
10
V
V
All
All
-
-
1.0
50
mA
µA
Module Output Voltage @ Logic Hi
AEH/ALH60x48N
-
-
0.2
V
Module Output voltage @ Logic Low
AEH/ALH60X48
-
-
0.2
V
Output Voltage Adjustment Range6
All
-
90
-
110
%Vo
3.3V
VO,CLAMP
3.90
4.10
5.00
V
Undervoltage Lockout
Turn-on Point
Turn-off Point
All
All
-
34.0
33.0
34.8
33.5
35.5
34.5
V
V
Isolation Capacitance
All
-
-
2700
-
PF
Isolation Resistance
All
-
10
-
-
MΩ
Calculated MTBF
(IO = IO,max ; TA = 25°C)
All
-
-
TBD
-
Hours
Output Overvoltage Clamp
Note:
6. For Output Voltage Adjustment setup, refer to Figures 3 and 4.
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 5 OF 21
Technical Reference Notes (AEH60/ALH60F48)
SAFETY APPROVAL
The series have been certified through:
• UL, cUL 60950 (Recognized)
• EN 60950 through TUV- PS
TO OSCILLOSCOPE
Vi(+)
Ltest
12 uH
BATTERY
Cs 220 uF
ESR < 0.1 OHM
@ 20 ºC, 100 kHz
33 uF
ESR < 0.7 OHM
@ 20 ºC, 100 kHz
Vi(-)
Note:
Measure the input reflected-ripple current with a simulated source inductance
(LTEST) of 12uH. Capacitor CS offsets possible battery impedance. Measure
current as shown above.
Figure 1. Input Reflected -Ripple Test Setup
COPPER STRIP
Vo(+)
0.1 uF
10 uF SCOPE
RESISTIVE
LOAD
Vo(-)
Note:
Use a 0.1µF @50V X7R ceramic capacitor and a 10µF @ 25V tantalum
capacitor. Scope measurement should be made using a BNC socket.
Position the load between 51 mm and 76 mm (2 in. and 3 in.) from module.
Figure 2. Peak to Peak Output Noise and Ripple Test Measurement Setup
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 6 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Basic Operation and Features
AEH60 / ALH60 converters were designed specifically to address applications where ultra high power density is required.
These modules provide basic insulation and 1500V isolation with very high output current capability in an industry
standard half size module. Operating from 36 to 75V input, they have standard features such as remote sense, trim, OVP,
OCP and OTP. AEH60 series devices will accept industry standard heat sinks to enhance thermal performance in
applications with conductive cooling.
Remote Sense (+Sense, -Sense)
Connect the + Sense and – Sense pins close to the load to allow the module to compensate for the voltage drop across
conductors carrying high load current. If remote sense is not required (for example if the load is close to the module) the
sense pins should be connected to the corresponding output pins. Maximum voltage drop compensation is 10% Vout. It is
important to avoid introducing lumped inductance or capacitance into the remote path. Do not connect remote sense lines
“beyond” any external output filter stages used with the module.
Trim Function
Output voltage adjustment is accomplished by connecting an external resistor between the Trim Pin and either the +Sense
or –Sense Pins.
To adjust Vo to a higher value, please refer to Figure 3.
An external resistor, Radj_up should be connected
between the Trim Pin and the +Sense Pin. From Equation
(1), Radj_up resistor can be determined for the required
output voltage increment.
Equation (1)
Radj_up = Vo*(100 + %Vo,adj)
1.225*%Vo,adj
100+ 2%Vo,adj
%Vo,adj
where: Radj_up - in kΩ
%Vo, adj - percent change in output voltage
kohm
Figure 3. Radj_up Setup to increase Output Voltage
To adjust Vo to a lower value, please refer to Figure 4.
An external resistor, Radj_down should be connected
between the Trim Pin and the -Sense Pin. From Equation
(2), Radj_down resistor can be determined for the
required output voltage change.
Equation (2)
Radj_down
100
%Vo, adj
2
. kohm
Figure 4. Radj_down Setup to decrease Output Voltage
where: Radj_down - in kΩ
%Vo, adj - percent change in output voltage
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 7 OF 21
Technical Reference Notes
Hercules (AEH/ALH60) Open
Frame or HS Adapted
Basic Operation and Features (continued)
Output Over Voltage Protection
The output over voltage system consists of a separate control loop, independent of the primary feedback path. This control
loop has a higher voltage set point than the main circuit. In a fault condition, the converter latches which ensures that the
output voltage does not exceed VO,CLAMP,max. The converter will operate back normally once the fault is removed and the
input voltage is cycled or the enable pin is toggled.
Output Over Current Protection
To provide protection in an output overload or short circuit condition, the converter is equipped with current limiting
circuitry and can endure fault conditions for an unlimited duration. At the point of current-limit inception, the converter
latches, causing the output current to be limited both in peak and duration. The converter will operate back normally once
the overload/ fault is removed and the input voltage is cycled or the enable pin is toggled.
Enable Function
Two enable options are available. Positive Logic Enable (no suffix required in part number) and Negative Logic Enable
(suffix “N”). Positive Logic Enable turns the converter on during a logic-high voltage on the enable pin, and off during a
logic-low. Negative Logic Enable turns the converter off during a logic-high and on during a logic-low.
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 8 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Performance Curves
EFFICIENCY
3V3 Efficiency VS Load Current @ Tc = 70 deg C
95%
95%
90%
90%
EFFICIENCY [%]
EFFICIENCY [%]
3V3 Efficiency VS Load Current @ Tc = 25 deg C
85%
80%
75%
70%
Vin = 36Vdc
65%
Vin = 48Vdc
60%
Vin = 75Vdc
85%
80%
75%
70%
Vin = 36Vdc
65%
Vin = 48Vdc
60%
Vin = 75Vdc
55%
55%
0
10
20
30
40
LOAD CURRENT [Amp]
50
60
Figure 5. AEH/ALH60 3V3 Efficiency Curve at TC = 25°C
0
10
20
30
40
LOAD CURRENT [Amp]
50
60
Figure 6. AEH/ALH60 3V3 Efficiency Curve at TC = 70°C
TRANSIENT RESPONSE
Figure 7. 3V3 output: 50% to 75% load change with no
external capacitor at 0.1A/uS slew rate (CH1 at
1A/10mV).
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
Figure 8: 3V3 output: 50% to 75% load change with
10,000uF external capacitor at 0.1A/uS slew
rate (CH1 at 1A/10mV).
SHEET 9 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Performance Curves (continued)
CURRENT VS TEMPERATURE CURVES
3V3 ALH (Open Frame) Load Current VS. Temperature
LOAD CURRENT[Amp]
60
50
40
30
Nat. Conv.
0.5 m/s (100 ft/min)
1.0 m/s (200 ft/min)
2.0 m/s (400 ft/min)
20
10
0
25
30
35
40
45
50
55
60
65
70
75
80
85
80
85
AMBIENT TEMPERATURE (ºC)
Figure 9. Load Current VS. Temperature (Open Frame)
3V3 AEH (baseplate) Load Current VS. Temperature
LOAD CURRENT [Amp]
60
50
40
30
Nat. Conv.
0.5 m/s (100 ft/min)
1.0 m/s (200 ft/min)
2.0 m/s (400 ft/min)
20
10
0
25
30
35
40
45
50
55
60
65
70
75
AMBIENT TEMPERATURE (ºC)
Figure 10. Load Current VS. Temperature (Baseplate)
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 10 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Performance Curves (continued)
STARTUP CHARACTERISTICS
Figure 11. AEH60F48 (3.3V): O/P startup characteristic
with no external capacitor at Vin = 48V / 20A
resistive load
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
Figure 12. AEH60F48 (3.3V): O/P startup characteristic
with 9400 uF external capacitor at Vin = 48V /
20A resistive load.
SHEET 11 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Input Filter for FCC Class B Conducted Noise
A reference design for an input filter that can provide FCC Class B conducted noise levels is shown below (See Figure 13).
Two common mode connected inductors are used in the circuit along with balanced bypass capacitors to shunt common
mode currents into the ground plane. Shunting noise current back to the converter reduces the amount of energy reaching
the input LISN for measurement.
The application circuit shown has an earth ground (frame ground) connected to the converter output (-) terminal. Such a
configuration is common practice to accommodate safety agency requirements. Grounding an output terminal results in
much higher conducted emissions as measured at the input LISN because a hard path for common mode current back to the
LISN is created by the frame ground. “Floating” loads generally result in much lower measured emissions. The electrical
equivalent of a floating load, for EMI measurement purposes, can be created by grounding the converter output (load)
through a suitably sized inductor(s) while maintaining the necessary safety bonding.
Also shown is a sketch of a PCB layout used to achieve Class B conducted noise levels (See Figure 14). It is important to
avoid extending the ground plane or any other conductors under the inductors (particularly L2) because capacitive coupling
to that track or plane can effectively bypass the inductor and degrade high frequency performance of the filter.
PARTS LIST
CIRCUIT CODE
L1, L2
C1, C3, C4, C5, C6, C11, C12
C2, C7, C9
C13, C14
C8, C10
DESCRIPTION
Pulse Engineering P0353 / 590uH
0.01uF / 2000V
100uF / 100V Aluminum
470pF / 100V Ceramic
2.2uF / 100V Film
C13
+ Vin
C3
+
48 VDC
INPUT
-
+
C1
C5
L1A
L2A
+
C2
C7
C11
+
C8
C9
CONVERTER
C10
L2B
L1B
- Vin
C4
+ Vout
- Vout
C6
C14
C12
Figure 13: Class B Filter Circuit
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 12 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Input Filter for FCC Class B Conducted Noise (continued)
GND PLANE
C11
C13
C3
+48 VDC
C1
1
3
L1
A/B
C2
48 V Return
2
1
C7
C8
4
C4
+ Vin
C5
C
O
N
V
E
R
T
E
R
3
L2
A/B
2
C9
C10
4
C6
TOP
VIEW
- Vin
C14
C12
GND PLANE
Figure 14: Recommended PCB Layout for Class B Filter
Input Noise Spectrum
FCC Part 15 & CISPR 22 A & B Limits - conducted noise
db/uv
80
LISN Voltage
90
50
AVERAGE
LIMITS
70
60
40
30
20
10
0
2.E+04 5.E+04 1.E+05 3.E+05 7.E+05 2.E+06 4.E+06 9.E+06 2.E+07
Frequency (Hz)
Figure 15: AEH60F48 and ALH60F48 Noise Spectrum
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 13 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Thermal Considerations
While the ALH60 (Open Frame Converter) is designed to provide the maximum performance at the lowest profile, the
AEH60 (Power Converter with HS adapter) operates in a variety of thermal environments. Sufficient cooling should be
provided to help ensure reliable operation of either device. Heat generating components are thermally coupled to the
adapter where heat energy is removed by conduction, convection, and radiation to the surrounding environment. Heat sinks
can provide enhanced output performance as shown below. Proper cooling can be verified by measuring the case
temperature (Center of adapter plate/baseplate).
HEAT TRANSFER CHARACTERISTICS
Increasing airflow over the converter enhances heat transfer via convection. Figure 16 shows worse case maximum power
that can be dissipated by the converter, without exceeding the maximum adapter plate temperature, versus local ambient
temperature (TA) for natural convection through 2.0 m/s (400 ft/min). Figure 17 shows actual maximum power that can be
dissipated through both the adapter plate and through the output pins (unit soldered into a 4” square copper plane (2 Oz.) or
equivalent).
AEH60 Series
Power Dissipation vs Temp
Forced Convection without HS
Power Dissipation (Watts)
30
Nat. Conv.
1.0 m/s (200 ft/min)
25
1.5 m/s (300 ft/min)
2.0 m/s (400 ft/min)
20
15
10
5
0
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
Ambient Temperature (ºC)
Figure 16. Forced Convection Power Dissipation
Note: This is worse case dissipation - additional Heat transfer through O/P pins will increase
allowable dissipation considerably. See Figure 17.
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 14 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Thermal Considerations (continued)
AEH60 Series
Actual Power Dissipation vs Temp
Forced Convection without HS
Power Dissipation [W]
30
Nat. Conv.
1.0 m/s (200 ft/min)
1.5 m/s (300 ft/min)
2.0 m/s (400 ft/min)
25
20
15
10
5
0
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
Ambient Temperature (ºC)
Figure 17. Actual Measured Forced Convection Power Dissipation
Note: This is an actual measured maximum dissipation with heat transfer through output pins
included.
Power Dissipation vs Output Current
Tc = 25 Deg Celsius
Power Dissipation [W]
25.0
20.0
15.0
10.0
Vin = 36 Vdc
Vin = 48 Vdc
Vin = 75 Vdc
5.0
0.0
0
10
20
30
40
50
60
Output Current [Amps]
Figure 18. ALH/AEH60F48 Power Dissipation VS. Load Current.
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 15 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Thermal Considerations (continued)
HEATSINK SELECTION ILLUSTRATED
Figure 19 shows Case-to-Ambient Thermal Resistance, θ (°C/W), for AEH / ALH60 modules. These curves can be used
to predict which heat sink will be needed for a particular environment. As an illustration, let's refer to below application
requirement:
An application requires 45 Amps of 3.3V in a 55 °C environment with airflow of 1.0 m/s (200 ft/min); the
minimum heat sink required can be determined through Equation (3).
Equation (3)
θ
where:
TC, MAX
TA
PD
=
=
=
=
θ ≤ (TC, MAX – TA) / PD
Module’s Total Thermal Resistance
Case Temperature (100 °C)
Ambient Temperature (55 °C)
Power Dissipation (15W)
From Figure 18, the power dissipation for a 45A-load requirement can be determined (PD = 15W). Through Equation (3),
the Thermal Resistance can be calculated to be at θ ≤ 3.0 °C/W.
Based on Figure 19, the ¼" HS (heatsink), or greater, will be able to handle the required 45A-load at 55 °C environment
and with 1.0 m/s (200 ft/min) airflow.
AEH60 Series
Case to Ambient Thermal
Resistance Curves
No HS
1/4" HS
1/2" HS
1" HS
6
O
Thermal Resistance RCA ( C/W)
7
5
4
3
2
1
0
0
100
200
300
400
500
600
Airflow [ ft / min]
Figure 19. Case-to-Ambient Thermal Resistance vs. Air Velocity
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 16 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Stability:
Figures 20 and 21 are plots of internal Module Loop Gain and Phase Shift vs Frequency. Curves for typical
resistive and reactive loads are shown. System stability (Phase and Gain Margins) when the module is connected to other
loads can be determined from the Young's Stability Curves on Figures 23 and 24. Figure 22 shows an operating zone in
which phase margin can be determined for virtually any load resistance and shunt capacitance. See Ref. 1 for application of
curves.
60
LOOP PHASE SHIFT vs FREQUENCY
LOOP GAIN vs FREQUENCY
200
50
150
PHASE SHIFT deg
40
GAIN db
30
20
10
0
10
100
50
0
20
30
40
100
3
4
1 .10
1 .10
FREQUENCY Hz
50
100
5
1 .10
Figure 20. Loop Gain VS. Frequency at 0.171Ω load with
no output capacitance,
100
1 .10
1 .10
FREQUENCY Hz
3
4
1 .10
5
Figure 21. Phase Shift VS. Frequency at 0.171Ω load
with 9400uF cap load (3.9mΩ ESR)
PHASE MARGIN vs LOAD RES
PHASE MARGIN deg
90
No Output
Capacitance
80
70
60
50
0.01
9.4K uF,
3.9 mohms
0.1
1
LOAD RESISTANCE ohms
Figure 22: Phase Margin vs Load Resistance
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 17 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Young’s Stability Curves
PHASE MARGIN
YSC IMPEDANCE MAGNITUDE in OHMS
Impedance Magnitude ( Ohms )
1
0.1
0.01
1 .10
3
1 .10
100
3
1 .10
4
1 .10
5
4
1 .10
5
_______15°
_______30°
_______45°
_______60°
_______75°
_______90°
50
Impedance Phase Angle ( Degrees )
0
50
100
150
1 .10
100
3
1 .10
Frequency
Figure 23. Young’s Stability Curve – Phase Margin
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 18 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Young’s Stability Curves
GAIN MARGIN
YSC GAIN MARGIN
1
0.1
gain
0.01
3
1 . 10
4
1 . 10
5
1 . 10
6
1 . 10
3
1 . 10
100
4
1 . 10
5
1 . 10
4
1 . 10
5
1 . 10
______10db
______20db
______30db
______40db
______50db
50
0
Phase
50
100
150
200
3
1 . 10
100
Frequency
Figure 24. Young’s Stability Curve – Gain Margin
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 19 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Mechanical Specifications
Parameter
Dimension
Weight
Device
AEH/ALH
AEH/ALH
AEH
ALH
AEH
ALH
Symbol
L
W
H
H
PIN ASSIGNMENT
+ VIN
1
Enable ON/OFF
2
Case (AEH version)
3
- VIN
4
- Output
5
Note:
Min
-
Typ
2.40 [60.96]
2.30 [58.42]
0.50 [12.70]
0.40 [10.16]
130 [4.60]
110 [3.90]
6
7
8
9
Max
-
Unit
in [mm]
in [mm]
in [mm]
in [mm]
g [oz]
g [oz]
- Sense
Trim
+ Sense
+ Output
Nominal diameter for Pins 5 & 9 = 0.08", remaining pins at 0.04"
OUTLINE DRAWING
Figure 25. AEH60 - baseplate outline drawing (bottom view)
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 20 OF 21
Technical Reference Notes (AEH60/ALH60F48)
Mechanical Specifications (continued)
OUTLINE DRAWING
Figure 26. ALH60 - open-frame outline drawing (bottom view)
SOLDERING CONSIDERATIONS
The AEH/ALH series converters are compatible with standard wave soldering techniques. When wave soldering, the
converter pins should be preheated for 20–30 seconds at 110 °C and wave soldered at 260 °C for less than 10 seconds.
When hand soldering, the iron temperature should be maintained at 425°C and applied to the converter pins for less than 5
seconds. Longer exposure can cause internal damage to the converter. Cleaning can be performed with cleaning solvent
IPA or with water.
PART NUMBER CODING SCHEME FOR ORDERING
A x H60
x
y
z
y
48
z
Construction
E: Enhanced thermals; Heatsink adapted
L: Low profile; Open Frame
Output Voltage
F = 3.3V
Y = 1.8V
G = 2.5V
K = 1.2V
Option
N : Negative Enable
No Suffix : Positive Enable
Please call 1-888-41-ASTEC for further inquiries or visit us at www.astecpower.com
MODEL: AEH/ALH60F48
SEPTEMBER 26, 2002 - REVISION 02
SHEET 21 OF 21