HI-REL DESIGN
WAVE SOLDERABLE PACKAGE
ALL CERAMIC CAPACITORS
SURFACE MOUNT MAGNETICS
FEATURES
REPLACES APEX DHC2812S, DHC2815S
NO DERATING -- 55C TO +125C
HIGH ISOLATION -- 500V
OUTPUT VOLTAGE ADJUSTMENT STANDARD
REMOTE SHUTDOWN
11 50V INPUT @ 5 WATTS OUTPUT
DESCRIPTION
The DAC2812S and DAC2815S DC-DC converters are
higher output voltage companion devices to MSK's DHC
types. The DAC's provide the ruggedness, reliability and
features required to meet the advanced design challenges of
today's hi-rel market. This has been accomplished while
retaining a power density of 15 W/in
3
and 375 mW/gram of
power/package performance. The use of advanced substrate
and reflow soldering techniques during construction results in
a rugged, cost-effective and completely solderable package.
The DAC2800S hybrid converter series utilizes all ceramic
capacitors, surface mount magnetics, and ultrasonically bonded
wires to provide reliable operation at all operating tempera-
tures while surviving G forces of up to 500 G.
The DAC2800S series standard features include output
fault monitoring and/or turn on voltage point programming via
the shutdown pin. All three functions may be implemented
simultaneously with a minimum of external components. An
output voltage adjustment / load compensation pin which
adjusts outputs simultaneously is also standard.
Fault tolerant design protects these converters from most
external circuit faults. The +output and output adjust pins will
withstand +25 V while the shutdown pin will withstand +50 V,
protecting the converters from a variety of system or board
faults; e.g. solder bridges etc. Unique load fault protection
circuitry allows this converter to pull up loads having difficult
static load line characteristics and allows short term load
excursions significantly beyond ratings in most applications.
A transformer isolated flyback converter topology operating
at a switching frequency of 400 kHz allows operation over a
wide input voltage range. Internal filtering of outputs eliminates
the need for external capacitors in many applications.
The 8-pin package is hermetically sealed and isolated from
the internal circuits. Heat sinking is recommended for full
power operation at elevated ambient temperatures.
TYPICAL APPLICATION
BLOCK DIAGRAM
EXTERNAL CONNECTIONS
P W M
FEED FORWARD
CONTROLLER
ERROR AMPLIFIER
REFERENCE AND
ISOLATION
4
1
2
6
5
7
4707 Dey Road Liverpool, N.Y. 13088
M.S.KENNEDY CORP.
(315) 701-6751
DAC2800S
SERIES
ISO-9001 CERTIFIED BY DSCC
6W
DC-DC
CONVERTERS
Rev. A 3/01
1
1
2
3
4
5
+OUTPUT
OUTPUT COMMON
N/C
ADJUST/COMP
SHUTDOWN PLUS
8
7
6
CASE
-INPUT
+INPUT
ABSOLUTE MAXIMUM RATINGS
SPECIFICATIONS
DAC2812S DAC2815S
SPECIFICATIONS
PARAMETER
TEST CONDITIONS
1
MIN
TYP
MAX
MIN
TYP
MAX
UNITS
STEADY STATE
CHARACTERISTICS
INPUT VOLTAGE RANGE
55C
125C
11
28
50
11
28
50
Vdc
OUTPUT VOLTAGE
I
o
= 10%
11.9
12
12.1
14.9
15
15.1
Vdc
OUTPUT CURRENT 55C
125C
V
IN
= 16
40
450
360
mAdc
V
IN
= 11
50
417
333
mAdc
OUTPUT POWER 55C
125C
V
IN
= 16
40
5.4
5.4
W
V
IN
= 11
50
5
5
W
EFFICIENCY
I
o
= 100%
62
67
63
68
%
LINE REGULATION
V
IN
= 11
50
2
5
25
5
25
mV
LOAD REGULATION
Po = 0-5.4W
2
5
25
5
25
mV
OPERATING TEMPERATURE, CASE
55
125
55
125
C
TEMPERATURE COEFFICIENT
(Vout)
0.006
0.006
%/C
INPUT RIPPLE CURRENT
Bandwidth = 10kHz
1MHz
340
400
340
400
mArms
WITH 1H SERIES INDUCTANCE
Bandwidth = 10kHz
1MHz
45
55
45
55
mArms
OUTPUT RIPPLE VOLTAGE
Bandwidth = 10kHz
1MHz
15
60
15
60
mVrms
LOAD CAPACITANCE (OUTPUT
V
IN
= 16
40
200
200
F
OVER 55C
125C)
V
IN
= 11
50
100
100
F
SHORT CIRCUIT DISSIPATION
0.5
0.5
W
QUIESCENT INPUT CURRENT
50
70
50
70
mA
INHIBITED
0.09
1.25
2.5
0.09
1.25
2.5
mA
ISOLATION CHARACTERISTICS
(INPUT/OUTPUT/CASE)
LEAKAGE RESISTANCE
500 Vdc
100
100
M
LEAKAGE CAPACITANCE
10kHz
400
400
500
pF
DYNAMIC CHARACTERISTICS
LINE STEP RESPONSE, 10s rise
V
IN
= 16
40Vdc, I
o
= 100%
VOLTAGE CHANGE
200
200
mV
RECOVERY TIME (99%)
200
200
S
WITH 200 F OUTPUT
CAPACITORS
3
VOLTAGE CHANGE
100
100
mV
RECOVERY TIME (99%)
400
500
S
LOAD STEP RESPONSE, 10s rise
I
o
= 5010050%
VOLTAGE CHANGE
500
500
mV
RECOVERY TIME (99%)
150
150
S
WITH 200 F OUTPUT
CAPACITORS
3
VOLTAGE CHANGE
100
100
mV
RECOVERY TIME (99%)
500
600
S
START-UP OVERSHOOT
V
IN
= 0
28 Vdc
0
0
mV
SHUTDOWN DELAY
Pin 5 = >10
<8 Vdc
250
500
250
500
S
SHUTDOWN RECOVERY
Pin 5 = > 8
<10Vdc
40
60
40
60
mS
DAC2812S
DAC2815S
ABSOLUTE MAXIMUM RATINGS
DAC2812S
DAC2815S
INPUT VOLTAGE RANGE (Pin 7 to 6 or 5)
50Vdc
50Vdc
INPUT TRANSIENT (Pin 7 to 6)
80V @ 50ms
80V @ 50ms
OUTPUT CURRENT (Continuous)
450mA
360mA
TEMPERATURE, Storage
65C, 150C
65C, 150C
TEMPERATURE, Pin Soldering 10s
300C
300C
NOTES:
1. Unless otherwise stated T
C
= 25, V
IN
= 28V, Po = 5 watts, 2. Regulation measured on output pins 1/16" from case.
PACKAGE & THERMAL SPECIFICATIONS
MIN
TYP
MAX
UNITS
WEIGHT
14
GRAMS
TEMPERATURE RISE, junction to case
17
25
C
TEMPERATURE RISE, case to ambient
30
C/W
Rev. A 3/01
2
TYPICAL PERFORMANCE
GRAPHS
DAC2812S
0
4
5
6
OUTPUT CURRENT, P
OUT
(W)
10
12
13
11
14
15
16
LOW LINE DROP OUT
INPUT VOLTAGE, V
IN
(V)
1
2
3
10K
90K
60K
20K
30K 40K
INPUT VOLTAGE, V
IN
(V)
LINE TRANSIENT RESPONSE
EFFICIENCY CONTOURS
10
30
50
40
20
OUTPUT POWER, P
OUT
(W)
5
1
2
3
4
1.44
.18 .36
.72
1.08
1.8
5
1
2
3
4
SET POINT RESISTOR, R
SP
(
)
TIME, t (10msec/DIV)
12
16
20
24
28
TURN ON THRESHOLD
TURN ON VOLTAGE, E
TO
(V)
TURN ON RESPONSE
FREQUENCY, f (Hz)
100
AUDIO REJECTION
AUDIO REJECTION, A
V
(dB)
0
20
40
1K
10K
100K
60
80
RESPONSE, X (UNITS/DIV)
12V
0V
28V
V
OUT
V
IN
TEMP = 25
C
40%
50%
55%
60%
64%
67%
69%
INPUT VOLTAGE, V
IN
(V)
EFFICIENCY CONTOURS
OUTPUT CURRENT, P
OUT
(W)
TEMP =
125
C
40%
50%
56%
61%
64%
66%
INPUT VOLTAGE, V
IN
(V)
EFFICIENCY CONTOURS
11
50
40
20
30
10
50
40
20
30
OUTPUT CURRENT, I
OUT
(A)
TEMP = 55
C
30%
40%
50%
55%
67%
68%
68%
60%
65%
66%
63%
TIME, t (500
sec/DIV)
TIME, t (100
sec/DIV)
LOAD TRANSIENT RESPONSE 200
F
OUTPUT RESPONSE, X (UNITS/DIV)
OUTPUT RESPONSE, X (UNITS/DIV)
INCLUDES 200
F ON OUTPUT BUS
TIME, t (100
sec/DIV)
LOAD TRANSIENT RESPONSE
OUTPUT RESPONSE, X (UNITS/DIV)
450mA
450mA
LOAD
LOAD
V
OUT
V
OUT
V
OUT
V
IN
16V
OUTPUT LOAD = 450mA
225mA
225mA
500mV
100mA
200mV
100mA
200mV
20V
20V
5V
NO OUTPUT BUS CAPCITANCE
V
IN
= 28V
I
OUT
= 450mA
OUTPUT DC
POWER RATING
INCLUDES 200
F
ON OUTPUT
I
OUT
= 450mA
40V
INCLUDES 4.7
f ON OUTPUT BUS
Rev. A 3/01
3
TYPICAL PERFORMANCE
GRAPHS
DAC2815S
LINE TRANSIENT RESPONSE
0
4
5
6
OUTPUT CURRENT, P
OUT
(W)
10
12
13
11
14
15
16
LOW LINE DROP OUT
INPUT VOLTAGE, V
IN
(V)
1
2
3
10K
90K
60K
20K
30K 40K
INPUT VOLTAGE, V
IN
(V)
EFFICIENCY CONTOURS
10
30
50
40
20
OUTPUT CURRENT, P
OUT
(W)
5
1
2
3
4
5
1
2
3
4
5
1
2
3
4
SET POINT RESISTOR, R
SP
(
)
TIME, t (10msec/DIV)
12
16
20
24
28
TURN ON THRESHOLD
TURN ON VOLTAGE, E
TO
(V)
TURN ON RESPONSE
FREQUENCY, f (Hz)
100
AUDIO REJECTION
AUDIO REJECTION, A
V
(dB)
0
20
40
1K
10K
100K
60
80
RESPONSE, X (UNITS/DIV)
15V
0V
28V
V
OUT
V
IN
TEMP = 25
C
40%
50%
56%
60%
64%
68%
70%
INPUT VOLTAGE, V
IN
(V)
EFFICIENCY CONTOURS
OUTPUT CURRENT, P
OUT
(W)
TEMP =
125
C
40%
50%
56%
61%
65%
67%
68%
INPUT VOLTAGE, V
IN
(V)
EFFICIENCY CONTOURS
10
50
40
20
30
10
50
40
20
30
OUTPUT CURRENT, P
OUT
(W)
TEMP = 55
C
40%
50%
58%
69%
72%
62%
66%
TIME, t (500
sec/DIV)
TIME, t (100
sec/DIV)
LOAD TRANSIENT RESPONSE 200
F
OUTPUT RESPONSE, X (UNITS/DIV)
OUTPUT RESPONSE, X (UNITS/DIV)
INCLUDES 200
F ON OUTPUT BUS
TIME, t (100
sec/DIV)
LOAD TRANSIENT RESPONSE
OUTPUT RESPONSE, X (UNITS/DIV)
360mA
360mA
LOAD
LOAD
V
OUT
V
OUT
V
OUT
V
IN
16V
40V
OUTPUT LOAD = 360mA
180mA
180mA
500mV
100mA
200mV
100mA
200mV
20V
20V
5V
NO OUTPUT BUS CAPCITANCE
V
IN
= 28V
I
OUT
= 360mA
OUTPUT DC
POWER RATING
INCLUDES 200
F
ON OUTPUT
V
OUT
= 360mA
INCLUDES 4.7
F ON OUTPUT BUS
Rev. A 3/01
4
OUTPUT ADJUST / COMP
The output voltage of the DAC2812S and DAC2815S may
be adjusted from 90% to 110% of nominal value by the use of
a 150K
potentiometer as shown. Adjustment beyond this
range is possible, however certain characteristics of the
converter such as but not limited to input voltage range,
efficiency, ripple and temperature performance will change.
Characterization by the user is recommended in such applica-
tions.
Adjust/comp (pin 4) may be driven by external circuitry
referenced to pin 2 (-output) if desired. Grounding pin 4 causes
voltage to increase (25% typically) while driving pin 4 above
1.3 V causes output voltage to decrease. Pin 4 may be driven
negative without damage, however the resultant increase in
converter output voltage should be considered. Pin 4 may be
driven through 10K
or more if connection of the comp
function is also required.
The comp function of pin 4 allows load transient response to
be tailored to suit specific application requirements. This
feature may be utilized by connecting a 10 or less nF capacitor
between pins 4 and 1.
Note: The DAC2812S and DAC2815S use pin 4 while the
DHC2803S and DHC2805S use pin 3.
SHUTDOWN PLUS
Pin 5 is used for remote shutdown, output fault detection,
and/or setting the input voltage point at which the converter will
turn on as shown in the typical application diagram. No
connection to pin 5 is necessary for normal operation of the
converter. Pin 5 is referenced to pin 7 (-input).
Shutdown may be implemented by simply connecting pin 5
to an open collector logic output or switch rated at 2.5 mA, 25
Vdc or higher.
Input voltage turn on point is programmed with a single
resistor from pin 5 to 7. An input turn on/off hysteresis (typically
3.5% of Vin) will be observed. This should be considered when
making or verifying set point adjustment. The value of the
setpoint resistor may be determined by the following:
R =
210 * 10
3
E
TO
9.5
(+/ 10% accuracy at 25
O
C)
Set point temperature coefficient is typically + 400ppm/
O
C
Output fault monitoring is accomplished by observing pin 5
4
1
2
150K
10nF
with a high impedance monitoring circuit. Pin 5 voltage drops
from over 10 V to below 1 V when a load fault causes the
converters fault protection circuitry to activate. It will remain
low for at least 100 mS and return high. If the load fault is still
present pin 5 will return low and the cycle will repeat. A resistor
> 400 K
from pin 5 to 7 provides pull down for pin 5 if there
is no input setpoint programming resistor already in place.
LOAD FAULT RESPONSE
The MSK families of DC-DC converters share load fault
philosophies. Load fault conditions include short-circuit and
severe overload conditions. The DAC2800 converter series
responds to load faults by turning off all power conversion
circuits for 250 mS and then attempting to restart for 10 mS
(typical). The net "on" duty factor during a fault is very low
resulting in low converter dissipation and immunity from over-
heating at 125C. Current beyond rated can flow into the load
at startup time. This allows the converter to bring up capacitive
and other difficult load types more reliably than competing
converters.
Vo
NORMAL
TIME
NORMAL
LOAD FAULT
O
I
o
O
TYPICAL PERFORMANCE
GRAPHS
DAC2812S DAC2815S
Rev. A 3/01
5
The information contained herein is believed to be accurate at the time of printing. MSK reserves the right to make
changes to its products or specifications without notice, however, and assumes no liability for the use of its products.
Please visit our website for the most recent revision of this datasheet.
M.S. Kennedy Corp.
4707 Dey Road, Liverpool, New York 13088
Phone (315) 701-6751
FAX (315) 701-6752
www.mskennedy.com
NOTE: ALL DIMENSIONS ARE 0.010 INCHES UNLESS OTHERWISE LABELED.
ESD Triangle indicates Pin 1.
DAC2812S
The above example is an industrial grade 12V single output converter
ORDERING INFORMATION
SCREENING
BLANK= INDUSTRIAL; E= EXTENDED RELIABILITY;
H= CLASS H; K= CLASS K
SINGLE OUTPUT
OUTPUT VOLTAGE
12=12V; 15=15V
NOMINAL INPUT VOLTAGE
GENERAL PART NUMBER
Rev. A 3/01
6
MECHANICAL SPECIFICATIONS
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