Technical Reference Notes
ALD12/18/20/25 Series
(Single Output 16
th
Brick)
ALD12/18/20/25 Single Output 16
th
Brick: 60Watts
The ALD12/18/20/25 series is Astec’s latest 16
th
Brick industry standard offering. Operating from an input voltage range of 36V to
75V, the series provides 6 configured outputs from 1.2V all the way up to 5V. It delivers up to 25A max current for 1.8V and
lower at impressive levels of efficiency. The series comes with industry standard features such as Input UVLO; non-latching OCP,
OVP and OTP; Output Trim; Differential Remote Sense pins. With its wide operating temperature range of -40°C to 85°C
ambient, the converters are deployable into almost any environment.
Electrical Parameters
Input
Input Range
Input Surge
36-75 VDC
100V / 100ms
Control
Enable
TTL compatible
(Positive or Negative Logic Enable Options)
Output
Special Features
•
•
•
•
•
•
•
•
Industry Standard 16
th
Brick Footprint
Low Ripple and Noise
Output pre-bias startup
Regulation to zero load
High Capacitive Load Start-up
Fixed Switching Frequency
Industry standard features: Input UVLO;
Enable; non-latching OVP, OCP and OTP;
Output Trim, Differential Remote Sense
Meets Basic Insulation
Load Current
Line/Load Regulation
Ripple and Noise
Adjust Range
Transient Response
Remote Sense
Over Current
Protection
Over Voltage
Protection
Over Temperature
Protection
Up to 25A max (V
O
≤
1.8V)
< 1% V
O
40mV
P-P
typical
±10% V
O
3% Typical deviation
50% to 75% Load Change
80µs settling time (Typ)
µ
+10%V
O
120% max
130% max
110
°
C
Environmental Specifications
•
•
•
-40ºC to 85ºC Operating Temperature
-40ºC to 125ºC Storage Temperature
MTBF > 1 million hours
Safety
UL + cUL 60950, Recognized
EN60950 through TUV-PS
MODEL: ALD12/18/20/25 SERIES
AUGUST 17, 2005 – REVISION C
SHEET 1 OF 20
Technical Reference Notes
ALD12/18/20/25 Series
(Single Output 16
th
Brick)
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
1
Continuous
Transient (100ms)
Isolation Voltage
Input to Output
Operating Temperature
Storage Temperature
Operating Humidity
Max Voltage at Enable Pin
Max Output Power
Device
All
Symbol
V
IN
V
IN, trans
All
All
All
All
All
A (5V0)
F (3V3)
G (2V5)
Y (1V8)
M (1V5)
K (1V2)
Min
-0.3
-
1500
-40
-40
10
-0.6
-
-
-
-
-
-
Typ
-
-
-
-
-
-
-
-
-
-
-
-
-
Max
75
100
-
85
125
85
25
60
60
50
45
38
30
Unit
Vdc
Ta
T
STG
-
Vdc
ºC
ºC
%
Vdc
W
W
W
W
W
W
INPUT SPECIFICATIONS
Parameter
Operating Input Voltage Range
Input Under-Voltage Lock-out
T_ON Threshold
T_OFF Threshold
Input Current
1
(V
IN
= V
IN, Min
; I
O
= I
O, Max
)
Device
All
All
Symbol
V
IN
Min
36
34.0
31.0
-
-
-
-
Typ
48
34.8
32.5
-
-
-
-
Max
75
36.0
33.5
2.4
2.4
1.9
1.6
1.4
1.1
4.1
3.9
3.4
3.4
3.4
2.6
10
-
1
Unit
Vdc
Vdc
A
Max P
diss
@ I
O
= 0A
(V
IN
= V
IN, Nom
; T
A
≥
25°C)
Input Ripple Current
2
5Hz to 20MHz
Input Voltage Rise Time
10% to 90% of Vout
Inrush Current
5V0 (A)
3V3 (F)
2V5 (G)
1V8 (Y)
1V5 (M)
1V2 (K)
5V0 (A)
3V3 (F)
2V5 (G)
1V8 (Y)
1V5 (M)
1V2 (K)
All
All
All
I
IN-MAX
-
-
-
-
-
-
-
-
W
I
I1
-
-
-
1
-
mAp-p
V/ms
A
2
/s
I
2
/s
-
MODEL: ALD12/18/20/25 SERIES
AUGUST 17, 2005 – REVISION C
SHEET 2 OF 20
Technical Reference Notes
ALD12/18/20/25 Series
(Single Output 16
th
Brick)
Electrical Specifications (continued)
OUTPUT SPECIFICATIONS
Parameter
Output Voltage Set point
V
IN
= V
IN, MIN
to V
IN,MAX;
I
O
=I
O,Max
Device
5V0 (A)
3V3 (F)
2V5 (G)
1V8 (Y)
1V5 (M)
1V2 (K)
Max
Symbol
V
O,SET
Min
4.930
3.260
2.465
1.770
1.470
1.180
-
-
-
-
0
0
0
0
0
0
-
4
13.0
19.5
21.5
26.5
26.5
26.5
5.9
3.9
3.0
2.1
1.8
1.4
110
90.0
89.0
88.5
87.0
83.5
82.0
Typ
5.000
3.300
2.500
1.800
1.500
1.200
0.1
0.1
0.3
40
-
-
-
-
-
-
-
-
-
-
-
-
-
-
6.2
4.1
3.2
2.4
2.1
1.6
-
91.0
90.0
89.5
88.0
84.5
83.0
Max
5.070
3.340
2.535
1.830
1.530
1.220
0.4
0.4
0.8
100
12
18
20
25
25
25
10,000
-
19
25
30
34
34
34
6.9
4.9
3.9
2.9
2.5
2.1
120
94.0
93.0
92.0
90.0
88.0
86.0
Unit
Vdc
Vdc
Vdc
Vdc
Vdc
Vdc
%Vo
%Vo
%Vo
mVp-p
A
Output Regulation
Line: V
IN
= V
IN, Min
to V
IN,
Load: I
O
= I
O, Min
to I
O, Max
All
All
All
All
5V0 (A)
3V3 (F)
2V5 (G)
1V8 (Y)
1V5 (M)
1V2 (K)
All
5V0 (A)
3V3 (F)
2V5 (G)
1V8 (Y)
1V5 (M)
1V2 (K)
5V0 (A)
3V3 (F)
2V5 (G)
1V8 (Y)
1V5 (M)
1V2 (K)
All
5V0 (A)
3V3 (F)
2V5 (G)
1V8 (Y)
1V5 (M)
1V2 (K)
-
-
-
-
I
O
Temperature: T
A
= -40 ºC to
+85ºC
Ripple and Noise
3
Peak-to-Peak: (5Hz to 20MHz)
Output Current
External Load Capacitance
Capacitor ESR
Output Current-limit Inception
V
OUT
= 90% V
O,SET
(Autorecovery)
-
I
O
µF
mΩ
A
Over Voltage Range
(Autorecovery)
V
Over Temperature Range
(AVG. PCB TEMP) - Auto recovery
°C
%
%
%
%
%
%
Efficiency
V
IN
= V
IN-NOM
I
O
= I
O,MAX
T
A
=25°C
η
η
η
η
η
η
MODEL: ALD12/18/20/25 SERIES
AUGUST 17, 2005 – REVISION C
SHEET 3 OF 20
Technical Reference Notes
ALD12/18/20/25 Series
(Single Output 16
th
Brick)
Electrical Specifications (continued)
OUTPUT SPECIFICATIONS
(continued)
Parameter
Turn-On Response Time
4
V
IN
= V
IN-MIN to
V
IN-MAX
Enable to Output Turn-ON Delay
V
IN
= V
IN-MIN to
V
IN-MAX
I
O
= I
O,MIN to
I
O,MAX
+V
IN
to Output Turn-On Delay
Enable Pin: Active
V
IN
= V
IN-MIN to
V
IN-MAX
I
O
= I
O,MIN to
I
O,MAX
Switching Frequency
Dynamic Response:
C
O
= use Figure 2 test setup
Peak Deviation for Load Step
Change from
I
O
= 50% to 75% of I
O, Max
:
Settling Time to within 1% of
output set point voltage – V
O,SET
:
Peak Deviation for Load Step
Change from
I
O
= 50% to 25% of I
O, Max
:
Settling Time to within 1% of
output set point voltage – V
O,SET
:
Output Overshoot at Turn-on
Passive Resistive Full Load
Output Enable ON/OFF
Enable Signal Slew Rate
Negative Enable ("N" suffix)
Enable Pin Voltage: Mod-ON
Mod-OFF
Positive Enable (No suffix)
Enable Pin voltage: Mod-ON
Mod-OFF
Output Voltage Remote Sensing
Output Voltage Trim Range
5
Device
All
All
Symbol
-
-
Min
-
-
Typ
2
-
Max
5
10
Unit
ms
ms
All
-
-
-
10
ms
All
2V5, 5V0
∆I
O
/∆t
-
-
560
650
-
625
725
0.1
690
800
-
KHz
A/µs
All
All
All
All
Vo
≤
1V8
Vo > 1V8
All
N suffix
-
-
-
-
3
80
6
200
% Vo
µs
% Vo
µs
%Vo
-
-
-
-
-
-
-
-
-
-
-
0.01
-0.5
2.95
2.95
-0.5
-
90
3
80
0
0
-
-
-
-
-
-
6
200
5
4
-
1.2
20
20
1.2
10
110
V/ms
V
V
V
%V
O
%V
O
No suffix
-
-
-
All
All
NOTES: 1. The converter is not internally fused; an external fuse must be used.
2. Refer to Figure 1 for the input reflected ripple test setup.
3. Refer to Figure 2 for the Output Ripple and Noise Test Measurement Setup.
4. Measure output rise time from 10%V
O
to 90%V
O
.
5. Refer to the output trim equations provided (Equations 1 and 2).
MODEL: ALD12/18/20/25 SERIES
AUGUST 17, 2005 – REVISION C
SHEET 4 OF 20
Technical Reference Notes
ALD12/18/20/25 Series
(Single Output 16
th
Brick)
Electrical Specifications (continued)
SAFETY AGENCY / MATERIAL RATING / ISOLATION
Parameter
Safety Approval
Material Flammability Rating
Parameter
Input to Output Capacitance
Input to output Resistance
Input to Output Insulation Type
Device
All
All
Device
All
All
All
UL/cUL 60950
TUV EN 60950
UL94V-0
Symbol
Min
-
-
-
Typical
1000
10
Basic
Max
-
-
-
Unit
pF
Mohms
-
TO OSCILLOSCOPE
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(+)
Vi(-)
Measure input reflected-ripple current with a simulated source inductance (Ltest) of 12 uH.
Capacitor Cs offsets possible battery impedance. Measure current as shown above.
Figure 1. Input Reflected Ripple Current Measurement Setup.
COPPER STRIP
Vo(+)
0.1 uF
Vo(-)
10 uF SCOPE
RESISTIVE
LOAD
Use a 0.1µF @50V X7R ceramic capacitor (connected an inch away from the output
terminals of the UUT) and a 10µF @ 25V tantalum capacitor (2 inches away from the output
terminals of the UUT). Scope measurement should be made using a BNC socket, positioned 3
inches away from output terminals of the converter.
Figure 2. Peak to Peak Output Noise Measurement Setup.
MODEL: ALD12/18/20/25 SERIES
AUGUST 17, 2005 – REVISION C
SHEET 5 OF 20
