Not Recommended for New Designs
BCM
®
Bus Converter
B048x096y24A
S
C
NRTL
US
Unregulated DC-DC Converter
FEATURES
DESCRIPTION
The VI Chip
®
bus converter is a high efficiency (>95%) Sine
Amplitude Converter™ (SAC™) operating from a 38 to 55 Vdc
primary bus to deliver an isolated, unregulated 7.6 to 11.0
output. The Sine Amplitude Converter offers a low AC
impedance beyond the bandwidth of most downstream
regulators; therefore capacitance normally at the load can be
located at the input to the Sine Amplitude Converter. Since the
transformation ratio of the B048x096y24A is 1/5, the
capacitance value can be reduced by a factor of 41x, resulting
in savings of board area, materials and total system cost.
The B048x096y24A is provided in a VI Chip package
compatible with standard pick-and-place and surface mount
assembly processes. The co-molded VI Chip package provides
enhanced thermal management due to a large thermal
interface area and superior thermal conductivity. The high
conversion efficiency of the B048x096y24A increases overall
system efficiency and lowers operating costs compared to
conventional approaches.
PART NUMBERING
PART NUMBER
PACKAGE STYLE
PRODUCT GRADE
•
48 Vdc – 9.6 Vdc 240 W Bus Converter
•
High efficiency (>95%) reduces system
power consumption
•
High power density (>817 W/in
3
)
reduces power system footprint by >40%
•
Contains built-in protection features:
-
-
-
-
-
Undervoltage
Overvoltage Lockout
Overcurrent Protection
Short circuit Protection
Overtemperature Protection
•
Provides enable/disable control,
internal temperature monitoring
•
Can be paralleled to create multi-kW arrays
TYPICAL APPLICATIONS
•
High End Computing Systems
•
Automated Test Equipment
•
High Density Power Supplies
•
Communications Systems
B048
x
096
y
24A
F
= J-Lead
T
= Through hole
T
= -40° to 125°C
M
= -55° to 125°C
For Storage and Operating Temperatures see Section 6.0 General Characteristics
TYPICAL APPLICATION
enable / disable
switch
SW1
F1
PC
TM
BCM
®
Bus Converter
+In
+Out
V
IN
-In
-Out
L
O
A
D
BCM
®
Bus Converter
Page 1 of 18
Rev 1.1
08/2014
vicorpower.com
800 927.9474
Not Recommended for New Designs
1.0 ABSOLUTE MAXIMUM RATINGS
B048x096y24A
The absolute maximum ratings below are stress ratings only. Operation at or beyond these maximum ratings can cause permanent
damage to the device.
MIN
+IN to –IN
. . . . . . . . . . . . . . . . . . . . . . .
VIN slew rate (operational)
. . . . . . . . .
Isolation voltage, input to output
. . . .
+OUT to –OUT
. . . . . . . . . . . . . . . . . . .
-1
-1
-1
MAX
60
1
2250
16
UNIT
V
V/µs
V
V
Output current transient
(< = 10 ms, < = 10% DC)
. . . . . . . . . . . .
Output current average
. . . . . . . . . . . .
PC to –IN
. . . . . . . . . . . . . . . . . . . . . . . .
TM to –IN
. . . . . . . . . . . . . . . . . . . . . . .
MIN
-3
-2
-0.3
-0.3
MAX
38
30
20
7
UNIT
A
A
V
V
2.0 ELECTRICAL CHARACTERISTICS
Specifications apply over all line and load conditions unless otherwise noted;
Boldface
specifications apply over the temperature
range of
-40°C < T
C
< 100°C (T-Grade);
All other specifications are at
T
C
= 25ºC
unless otherwise noted.
ATTRIBUTE
POWERTRAIN
Input voltage range, continuous
Input voltage range, transient
Quiescent current
V
IN
to V
OUT
time
V
IN
_
DC
V
IN
_
TRANS
I
Q
T
ON
1
Full current or power supported, 50 ms max,
10% duty cycle max
Disabled, PC Low
V
IN
= 48 V, PC floating
V
IN
= 48 V, T
C
= 25ºC
No load power dissipation
P
NL
V
IN
= 48 V
V
IN
= 38 V to 55 V, T
C
= 25ºC
V
IN
= 38 V to 55 V
Inrush current peak
DC input current
Transformation ratio
Output power (average)
Output power (peak)
Output current (average)
Output current (peak)
I
INR
_
P
I
IN
_
DC
K
P
OUT
_
AVG
P
OUT
_
PK
I
OUT
_
AVG
I
OUT
_
PK
10 ms max, I
OUT
_
AVG
≤
25 A
V
IN
= 48 V, I
OUT
= 25 A; Tc = 25°C
Efficiency (ambient)
94.5
92.0
93.0
95.0
82.0
3.5
5.0
6.5
1.50
C
OUT
= 0 F, I
OUT
= 25 A, V
IN
= 48 V,
20 MHz BW, Section 10
Frequency up to 30 MHz,
Simulated J-lead model
Effective value at 9.6 V
OUT
0
5.4
7.8
9.2
1.55
200
600
45
1600
10.0
12.0
14.0
1.60
250
94.9
95.8
%
%
mΩ
mΩ
mΩ
MHz
mV
pH
µF
µF
95.8
%
V
IN
= 38 V to 55 V, I
OUT
= 25 A; Tc = 25°C
V
IN
= 48 V, I
OUT
= 13 A; Tc = 25°C
Efficiency (hot)
Efficiency (over load range)
V
IN
= 48 V, I
OUT
= 25 A; Tc = 100°C
5 A < I
OUT
< 25 A
I
OUT
= 25 A, Tc = -40°C
I
OUT
= 25 A, Tc = 25°C
I
OUT
= 25 A, T
C
= 100°C
10 ms max, P
OUT
_
AVG
≤
240 W
Worse case of: V
IN
= 55 V, C
OUT
= 1600 µF,
R
LOAD
= 376 mΩ
At P
OUT
= 240 W
K = V
OUT
/ V
IN
, at no load
1/5
240
240
25
38
3.5
500
38
38
2.0
560
4.5
55
55
3.0
750
6.0
11.0
8
12
W
V
V
mA
ms
SYMBOL
CONDITIONS / NOTES
MIN
TYP
MAX
UNIT
12
19
6.6
A
A
V/V
W
W
A
A
h
AMB
h
HOT
h
20%
R
OUT
_
COLD
R
OUT
_
AMB
R
OUT
_
HOT
F
SW
V
OUT
_
PP
L
OUT
_
PAR
C
OUT
_
INT
C
OUT
_
EXT
Output resistance
Switching frequency
Output voltage ripple
Output inductance (parasitic)
Output capacitance (internal)
Output capacitance (external)
BCM
®
Bus Converter
Page 2 of 18
Rev 1.1
08/2014
vicorpower.com
800 927.9474
Not Recommended for New Designs
2.0 ELECTRICAL CHARACTERISTICS (CONT.)
ATTRIBUTE
SYMBOL
CONDITIONS / NOTES
MIN
TYP
B048x096y24A
MAX
UNIT
PROTECTION
Input overvoltage lockout threshold
Input overvoltage recovery threshold
Input overvoltage lockout hysteresis
Overvoltage lockout response time
Fault recovery time
Input undervoltage lockout threshold
Input undervoltage recovery threshold
Input undervoltage lockout hysteresis
Undervoltage lockout response time
Output overcurrent trip threshold
Output overcurrent response time constant
Short circuit protection trip threshold
Short circuit protection response time
Thermal shutdown threshold
V
IN
_
OVLO
+
V
IN
_
OVLO
-
V
IN
_
OVLO
_
HYST
T
OVLO
T
AUTO
_
RESTART
V
IN
_
UVLO
-
V
IN
_
UVLO
+
V
IN
_
UVLO
_
HYST
T
UVLO
I
OCP
T
OCP
I
SCP
T
SCP
T
J
_
OTP
125
Effective internal RC filter
63
1
30
240
28.5
28.5
55.1
55.0
58.5
57.2
1.2
8
300
31.1
33.7
1.6
8
39
3.8
55
380
37.4
37.4
62
58
V
V
V
µs
ms
V
V
V
µs
A
ms
A
µs
ºC
Safe Operating Area Average & Peak
300
100
250
80
200
60
150
40
100
20
50
7.0
8.0
9.0
10.0
11.0
0
Output Voltage (V)
P (ave)
P (pk), < 10 ms
I (ave)
I (pk), < 10 ms
Figure 1 —
Safe operating area
BCM
®
Bus Converter
Page 3 of 18
Rev 1.1
08/2014
vicorpower.com
800 927.9474
Output Current (A)
Output Power (W)
Not Recommended for New Designs
3.0 SIGNAL CHARACTERISTICS
B048x096y24A
Specifications apply over all line and load conditions unless otherwise noted;
Boldface
specifications apply over the temperature
range of -40°C
< T
C
< 100°C (T-Grade);
All other specifications are at
T
C
= 25°C
unless otherwise noted.
PRIMARY CONTROL : PC
• The PC pin enables and disables the BCM. When held low,
• PC pin outputs 5 V during normal operation. PC pin internal bias
the BCM is disabled.
level drops to 2.5 V during fault mode, provided V
IN
remains
in the valid range.
• In an array of BCM modules, PC pins should be interconnected
to synchronize start up and permit start up into full load conditions.
SIGNAL TYPE
STATE
Regular
Operation
ANALOG
OUTPUT
Standby
Transition
Start Up
Start Up
Regular
Operation
DIGITAL
INPUT / OUPUT
Standby
ATTRIBUTE
PC voltage
PC available current
PC source (current)
PC resistance (internal)
PC capacitance (internal)
PC load resistance
PC time to start
PC enable threshold
PC disable duration
PC threshold hysteresis
Transition
PC enable to V
OUT
time
PC disable to standby time
PC fault response time
SYMBOL
V
PC
I
PC
_
OP
I
PC
_
EN
R
PC
_
INT
C
PC
_
INT
R
PC
_
S
T
ON
1
V
PC
_
EN
T
PC
_
DIS
_
T
V
PC
_
HYSTER
T
ON2
T
PC
-
DIS
T
FR
_
PC
From fault to PC = 2 V
V
IN
= 48 V for at least T
ON1
ms
50
Minimum time before attempting re-enable
Internal pull down resistor
Section 7
To permit regular operation
60
350
2.0
1
50
100
4
100
150
10
450
2.5
650
3.0
CONDITIONS / NOTES
MIN
4.7
2.0
50
50
TYP
5.0
3.5
100
150
400
1000
MAX UNIT
5.3
5.0
V
mA
µA
kΩ
pF
kΩ
ms
V
s
mV
µs
µs
µs
TEMPERATURE MONITOR : TM
• The TM pin monitors the internal temperature of the controller IC
• Can be used as a "Power Good" flag to verify that
within an accuracy of ±5°C.
the BCM module is operating.
• Is used to drive the internal comparator for Overtemperature Shutdown.
SIGNAL TYPE
STATE
ATTRIBUTE
TM voltage range
TM voltage reference
ANALOG
OUTPUT
Regular
Operation
TM available current
TM gain
TM voltage ripple
DIGITAL
OUTPUT
(FAULT FLAG)
Transition
TM capacitance (external)
TM fault response time
Standby
TM voltage
TM pull down (internal)
SYMBOL
V
TM
V
TM
_
AMB
I
TM
A
TM
V
TM
_
PP
C
TM
_
EXT
T
FR
_
TM
V
TM
_
DIS
R
TM
_
INT
Internal pull down resistor
25
From fault to TM = 1.5 V
10
0
40
50
C
TM
= 0 pF, V
IN
= 48 V, I
OUT
= 25 A
T
J
controller = 27°C
CONDITIONS / NOTES
MIN
2.12
2.95
100
10
120
200
50
3.00
TYP
MAX UNIT
4.04
3.05
V
V
µA
mV/°C
mV
pF
µs
V
kΩ
RESERVED : RSV
Reserved for factory use. No connection should be made to this pin.
BCM
®
Bus Converter
Page 4 of 18
Rev 1.1
08/2014
vicorpower.com
800 927.9474
4.0 TIMING DIAGRAM
Page 5 of 18
2
3
5
4
6
C
B
BCM
®
Bus Converter
G
D
A
E
F
V
OVLO
+
V
OVLO
–
1
V
IN
NL
V
UVLO
+
V
UVLO
–
PC
08/2014
Rev 1.1
I
OUT
I
SSP
I
OCP
H
5V
3V
3V
5V
2.5 V
C
500mS
before retrial
Vout
LL • K
Not Recommended for New Designs
800 927.9474
vicorpower.com
E: T
ON2
F: T
OCP
G: T
PC–DIS
H: T
SCP**
1: Controller start
2: Controller turn off
3: PC release
4: PC pulled low
5: PC released on output SC
6: SC removed
TM
3 V @ 27°C
0.4 V
Notes:
– Timing and signal amplitudes are not to scale
– Error pulse width is load dependent
A: T
ON1
B: T
OVLO*
C: T
AUTO_RESTART
D:T
UVLO
B048x096y24A
*Min value switching off
**From detection of error to power train shut down
