MSR SERIES
4 WATT
ABSOLUTE MAXIMUM RATINGS
Input Voltage
• 16 to 32 VDC
Output Power
• 3.2 to 4 watts depending on model
Lead Soldering Temperature (10 sec per lead)
• 300°C
Storage Temperature Range (Case)
• –-65°C to +150°C
DC/DC C
ONVERTERS
INHIBIT
Inhibit TTL Open Collector
• Logic low (output disabled)
≤
0.8 V
• Referenced to input common
• Logic high (output enabled)
≥
12 V
Open collector
TYPICAL CHARACTERISTICS
Output Voltage Temperature Coefficient
• MSR2805S 100 ppm/°C typ, 200 max.
• MSR28XXD 50 ppm/°C typ
• MSR285XXT 100 ppm/°C typ
Input to Output Capacitance
• 60 pF typical
Isolation
• 100 megohm minimum at 500 V
Conversion Frequency
• Single and dual output models, 80 kHz at
full load typical, variable frequency
• Triple output models, 200 kHz typical
fixed frequency
Inhibit Pin Voltage (unit enabled)
• 12 to 28 V
RECOMMENDED OPERATING CONDITIONS
Input Voltage Range
• 16 to 32 VDC continuous
• 40 V for 50 msec transient
Case Operating Temperature (Tc)
• –55°C to +85°C full power
• –55°C to +115°C absolute
Derating Output Power/Current
• Linearly from 100% at 85°C to 0% at 115°C
W
ARNING
: E
XTERNAL
C
APACITORS
R
EQUIRED
Electrical Characteristics: 25°C Tc, 28 VDC Vin, 100% load, unless otherwise specified.
SINGLE AND DUAL OUTPUT MODELS
PARAMETER
1
OUTPUT VOLTAGE
OUTPUT CURRENT
OUTPUT POWER
OUTPUT RIPPLE
LINE REGULATION
LOAD REGULATION
INPUT VOLTAGE
16 TO 32 V
IN
Tc = –55°C TO +85°C
BW = DC TO 1 MHz
16 TO 32 V
IN
NO LOAD TO FULL
Tc = –55°C TO +85°C
TRANSIENT 50 ms
INPUT CURRENT
NO LOAD
FULL LOAD
INHIBITED
EFFICIENCY
CONDITIONS
MIN
4.90
—
—
—
—
—
16
—
—
—
—
65
MSR2805S
TYP
5.0
—
—
75
5
25
28
—
7
—
—
70
MAX
5.10
700
3.5
150
10
50
32
40
10
192
2
—
MIN
±11.88
—
—
—
—
—
16
—
—
—
—
67
MSR2812D
TYP
±12
—
—
75
10
12
28
—
10
—
—
70
MAX
±12.12
±167
4.0
150
20
24
32
40
15
213
15
—
MIN
±14.85
—
—
—
—
—
16
—
—
—
—
67
MSR2815D
TYP
±15
—
—
75
10
12
28
—
10
—
—
70
MAX
±15.15
±133
4.0
150
20
24
32
40
15
213
15
—
%
mA
UNITS
VDC
mA
W
mV p-p
mV
mV
VDC
V
Notes
1. External capacitors required to prevent damage to internal circuitry (see
Table 1 for specifications).
2. Dual output models deliver up to 4 watts total for balanced or unbalanced
loads, however, the positive output should carry at least 25% of the total load.
SINGLE AND DUAL OUTPUT EXTERNAL CAPACITORS
O
PERATION WITHOUT EXTERNAL CAPACITORS WILL RESULT IN DAMAGE TO THE INTERNAL CIRCUITRY
.
TABLE 1: EXTERNAL CAPACITOR REQUIREMENTS
Required
Connection
Positive Output (12 & 13) to
Output Common (8 & 9)
Positive Output (10) to
Dual Outputs
2
Output Common (8)
MSR2812D
External Capacitor (14) to
and
Output Common (8)
3
MSR2815D
Negative Output (12) to
Output Common (8)
Model
Single Output
MSR2805S
Minimum
Capacitor Value
1
220 µF, 10 V
100 µF, 25 V
100 µF, 25 V
10 µF, 25 V
POSITIVE
INPUT
1, 2
INHIBIT
15
17, 18
INPUT
COMMON
FEEDBACK
POSITIVE
OUTPUT
10
OUTPUT
COMMON
8
LOGIC
TIMING
CONTROL
SWITCH
VOLTAGE
REGULATOR
+
+
EXTERNAL
CAPACITORS
100µF
NEGATIVE
OUTPUT
12
14
10µF
+
100µF
Notes – Table 1
1. Capacitors should be high quality, low ESR components —
solid tantalum is recommended.
2. See Figure 1 for connection diagram
3. Place positive side of capacitor toward pin 8.
EXTERNAL
CAPACITOR
TERMINAL
F
IGURE
1: D
UAL
O
UTPUT
E
XTERNAL
C
APACITOR
C
ONNECTIONS
B4-28
CRANE [ Crane Aerospace & Electronics. ]
