PRM48BH480T200B00 Data Sheet

PRM® Regulator
PRM48BH480T200B00
S
C
NRTL
US
High Efficiency Remote Sense PRM Converter
FEATURES
DESCRIPTION
®
TYPICAL APPLICATIONS
•
•
•
•
•
•
®
The VI Chip PRM Regulator is a high efficiency
converter, operating from a 38 to 55 Vdc input to generate
a regulated 5 to 55 Vdc output. The ZVS Buck – Boost
topology enables high switching frequency (~1 MHz)
operation with high conversion efficiency. High switching
frequency reduces the size of reactive components
3
enabling power density up to 1,300 W/in .
• 45 V (38 to 55 VIN), non-isolated ZVS buck-boost
regulator
• 5 to 55 V adjustable output range
• Building block for high efficiency DC-DC systems
2
• 200 W Output Power in 0.57 in footprint
• 97% typical efficiency, at full load
3
3
• 1,300 W/in (81 W/cm ) Power Density
• Enables a 48 V to 1.5 V, 130 A isolated, regulated
2
2
solution with total footprint of 1.7 in (11 cm )
• Flexible “Remote Sense” architecture optimizes
regulation / feedback loop design to fit application
requirements
• Current Feedback signal allows dynamic adjustment of
current limit setpoint
• 4.93 MHrs MTBF (MIL-HDBK-217Plus Parts Count)
High Efficiency Server Processor and Memory Power
High Density ATE system DC-DC power
Telecom NPU and ASIC core power
LED drivers
High Density Power Supply DC-DC rail outputs
Non-isolated power converters
The half VI Chip package is compatible with standard pickand-place and surface mount assembly processes with a
planar thermal interface area and superior thermal
conductivity.
In a Factorized Power Architecture™ system, the
®
PRM48BH480T200B00 and downstream VTM
transformer minimize distribution and conversion losses in
a high power solution.
An external control loop and current sensor maintain
regulation and enable flexibility both in the design of
voltage and current compensation loops to control of
output voltages and currents.
48 V to 1.2 V, 130A Voltage Regulator
Voltage
Control
Feedback
Enable/
Disable
Voltage
Reference
PR
PC
TM
+OUT
+IN
38 to 55 Vdc Input
PRM -IN
IF RE
IM
PC
+IN
TM
+OUT1
+OUT2
-IN
-OUT
SG VC
VC
Current
Sense
VTM PRM® Regulator
Rev 1.1
vicorpower.com
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800 927.9474
-OUT1
-OUT2
Load
PRM48BH480T200B00
1.0 ABSOLUTE MAXIMUM RATINGS
The ABSOLUTE MAXIMUM ratings below are stress ratings only. Operation at or beyond these maximum ratings can cause
permanent damage to device. Electrical specifications do not apply when operating beyond rated operating conditions. All
voltages are specified relative to SG unless otherwise noted. Positive pin current represents current flowing out of the pin.
PR
………………………………………………………………………..
PC
………………………………………………………………………..
TM
………………………………………………………………………..
+IN to –IN ……………………………………………………………………………
VS
………………………………………………………………………..
SG ……………………………………………………………………………
IF ……………………………………………………………………………
RE ……………………………………………………………………………
VC to –OUT
+OUT to –OUT
Output Current
Operating Analog IC Junction Temperature
Storage Temperature
………………………………………………………………………..
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
……………………………………………………………………………
Min
-0.3
Max
10.5
±10
5.7
±10
5.7
±1
62
10.5
±100
±100
5.7
5
18
±1.8
62
±5.5
125
125
-0.3
-0.3
-1
-0.5
-0.5
-0.3
-0.5
-1
-40
-40
Unit
V
mA
V
mA
V
mA
V
V
mA
mA
V
V
V
A
V
A
ºC
ºC
2.0 ELECTRICAL CHARACTERISTICS
Specifications apply over all line and load conditions, TJ = 25 ºC and output voltage from 20 V to 55 V, unless otherwise
noted. Boldface specifications apply over the temperature range of -40 ºC < TJ < 125 ºC (T-grade).
Attribute
Symbol
Conditions / Notes
Min
Typ
Max
Unit
38
0.001
45
55
1000
4
8.5
5.7
V
V/ms
W
mA
A
µF
mΩ
55
4.17
200
±10
V
A
W
µs
ms
%
See sec 10.6
%
POWER INPUT SPECIFICATION
VIN
dVIN/dt
P NL
I QC
IIN_DC
CIN_INT
RCin
Input Voltage range
VIN Slew Rate
No Load Power Dissipation
Input Quiescent current
Input Current
Input Capacitance (Internal)
Input Capacitance (Internal) ESR
0 < VIN < 18 V
PC High, VIN = 45 V
PC Low, VIN = 45 V
IOUT = 4.17 A, VIN = 38 V, V OUT = 48 V
Effective value, V IN = 45 V (see Fig. 20)
2.6
4.5
5.5
2
3
POWER OUTPUT SPECIFICATION
V OUT
I OUT
P OUT
TON
TOFF + TON
Output Voltage range
Output Current
Output Power
Output Turn-ON Delay
Current Sharing accuracy
Efficiency
Output
Output
Output
Output
Output
Discharge current
Voltage Ripple
Inductance (Parasitic)
Capacitance (Internal)
Capacitance (Internal) ESR
IOUT_PS
η
I OD
VOUT_PP
LOUT_PAR
COUT_INT
RCout
5
See Fig.16, SOA
See Fig.16, SOA
From PC pin release to V OUT, VIN pre-applied and TOFF already expired
From VIN applied to V OUT, PC floating
Equal input, output and PR voltage at full load; V IN = 45 V, V OUT = 48 V, exclusive of current limit
Equal input, output and PR voltage at full load;
Over line, trim, and temperature; exclusive of current limit
Nominal line, full load, V OUT = 48V
50% load and VOUT = 48 V; over temperature
50% load; over temperature
Section 4.0
COUT_EXT = 0 F, IOUT = 4.17 A, VIN = 45 V, V OUT = 48 V, 20 MHz BW
Frequency @ 1 MHz, Simulated J-Lead model
Effective value, V OUT = 48 V (see Fig. 20)
48
20
18.02
95.7
94.5
88.5
96.9
0.5
1020
2.5
2
3
1500
%
%
%
mA
mV
nH
µF
mΩ
POWERTRAIN PROTECTIONS
Input Undervoltage Turn-ON
Input Undervoltage Turn-OFF
Input Overvoltage Turn-ON
Input Overvoltage Turn-OFF
Overcurrent (IF) and Input
Over/Undervoltage Blanking Time
Output Overvoltage Threshold
Thermal Shutdown Setpoint
Overtemperature, Output Overvoltage
and PC Shutdown Response Time
Short Circuit Vout Threshold
Short Circuit Vout Recovery Threshold
Short Circuit Vpr Threshold
Short Circuit Vpr Recovery Threshold
Short Circuit Timeout
Short Circuit Fault Recovery Time
Output Power Limit
VIN_UVLO+
VIN_UVLOVIN_OVLO+
VIN_OVLOTBLANK
VOUT_OVLO+
TJ_OTP
TPROT
VSC_VOUT
VSC_VOUTR
VSC_VPR
VSC_VPRR
TSC
TSCR
P PROT
Instantanous powertrain shutdown, latched after TBLANK
Instantanous powertrain shutdown, latched after TBLANK
Instantaneous, latched shutdown
Instantaneous, latched shutdown; guaranteed by design, not production tested; V TM = 4.03V
35.75
33.56
57.24
58.44
37.13
31.97
55.91
59.91
V
V
V
V
50
120
150
µs
55.25
130
56.57
59.04
V
ºC
2
3.0
4.0
7.2
7.1
20
0.1
Short Circuit fault latched after V SC_VOUT and V SC_VPR thresholds persist for this time
200
PRM® Regulator
Rev 1.1
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7/2015
800 927.9474
µs
V
V
V
V
ms
ms
W
PRM48BH480T200B00
3.0 SIGNAL CHARACTERISTICS
Specifications apply over all line and load conditions, TJ = 25 ºC and Output Voltage from 20 V to 55 V, unless otherwise
noted. Boldface specifications apply over the temperature range of -40 ºC < TJ < 125 ºC (T-grade).
Primary Control
PC
• The PC pin enables and disables the PRM
• In PRM array configurations, PC pins should be connected in order to synchronize startup.
• It is a weak pull-down during any fault mode excluding short circuit. PC is a strong pull-down to SG if a Short Circuit fault is latched.
Signal Type
State
Attribute
Symbol
Conditions / Notes
V PC
Regular
PC Voltage
Operation
IPC_OP
PC Available Current
Analog Output
IPC_EN
After TOFF
PC Source Current
Startup
TOFF
Minimum Time to Start
Section 5.0
VPC_EN
Startup
PC Enable Threshold
Digital Input / Output
VPC_DIS
PC Disable Threshold
Standby
RPC_EXT Max Resistance to SG required to disable the PRM
PC Resistance to disable
IPC_SC
Digital Output [Short Circuit Fault]
Fault
PC Sink Current to SG
Short circuit, PC Voltage 1 V or above
IPC_FAULT Temperature, Over- and Under-Voltage, Overcurrent
Digital Output [All other Faults]
Fault
PC Sink Current to ~1V
Min
4.7
Voltage Source
VS
• Intended to power feedback components and/or auxiliary circuits.
Signal Type
State
Attribute
VS Voltage
Regular
VS Available Current
Operation
Analog Output
VS Voltage Ripple
Transition
Signal Type
State
Regular
Operation
Transition
Control Node
PR
• Modulator control node input
• Sinks constant current when externally driven
• Sources current when pulled below active range
Signal Type
State
Analog Input
Attribute
CVS_EXT
TFR_VS
1.8
1.75
18.0
2.50
2.40
30.0
3.20
300
25
10
Conditions / Notes
Iout = 0A, Cvs_ext=0. Maximum specification
includes powertrain operation in burst mode.
mA
90
10.0
Min
8.55
5
Typ
9.00
100
From fault recognition to VS = 1.5 V
Unit
V
µA
ms
V
V
Ω
mA
µΑ
Max
9.45
Unit
V
mA
400
mV
0.04
µF
µs
Unit
30
Min
Typ
Max
V RE
3.0
3.3
3.6
V
RE Available Current
RE Regulation
RE Voltage Ripple
PC to RE Delay
RE Capacitance (External)
I RE
%RE
VRE_PP
TPC_RE
CRE_EXT
8.0
across load and temperature
includes powertrain in burst mode
Fault detected
0.1
mA
%
mV
µs
µF
VS to RE Delay
TVS_RE
VS = 8.1 V to RE high, V IN > VIN_UVLO-
RE Voltage
Analog Output
Regular
Operation
Attribute
PR Voltage Active Range
PR Source Current
PR Sink Current
PR Resistance to SG (Internal)
VVS_PP
Max
5.3
Reference Enable
RE
• RE signals successful startup and powertrain ready to operate
• Regulated, delayed voltage source intended to power the feedback circuit voltage reference and current monitor
VS Capacitance (External)
VS Fault Response Time
Symbol
V VS
IVS
Typ
Symbol
Symbol
V PR
IPR
IPR_Low
Conditions / Notes
Conditions / Notes
VPR ≤ 0.79V
VPR > 0.79V
±2.5
100
100
1
ms
Min
0.79
Typ
Max
7.40
Unit
V
2
mA
250
500
750
µA
RPR
93.3
kΩ
Current Feedback
IF
• A voltage proportional to the PRM output current must be supplied externally to the IF pin in order for the device to properly protect overcurrent events and to enable output current limit (clamp)
• Overcurrent protection trip will cause instantaneous powertrain disable, latched after TBLANK
Signal Type
Analog Input
PRM® Regulator
Page 3 of 22
State
Regular
Operation
Attribute
Current Limit (clamp) Threshold
Symbol
VIF_IL
Overcurrent Protection Threshold
VIF_OC
IF Input Impedance
Current Limit Bandwidth
RIF
BW IL
Conditions / Notes
VIN = 45 V; TJ = 25 °C
Not Production Tested; Guaranteed by Design;
TJ = 25 °C
Rev 1.1
vicorpower.com
7/2015
800 927. 9474
Min
1.90
Typ
2.00
Max
2.10
2.58
2.69
2.80
2.11
2.13
2
2.15
Unit
V
kΩ
kHz
PRM48BH480T200B00
Temperature Monitor
TM
• The TM pin monitors the internal temperature of the PRM analog control IC.
• "Power Good" flag to verify that the PRM is operating
Signal Type
State
Attribute
TM Voltage
TM Voltage reference
Analog Output
Regular
TM Voltage Ripple
Operation
TM Available Current
Digital Output [Fault Flag]
Min
2.12
Typ
Max
4.04
VTM_AMB
TJ = 27 °C
2.94
3.00
3.06
VVS_PP
I TM
TM Disabled Current
I TM_DIS
Signal Ground
SG
• All control signals must be referenced to this pin, with the exception of VC
• SG is internally connected to -IN and -OUT
Signal Type
State
Attribute
Analog Input / Output
Any
Maximum Allowable Current
Symbol
ISG
VTM Control
VC
• Pulsed voltage source used to power and synchronize start up of downstream VTM
• If not used, must be resistively terminated to -OUT
Signal Type
State
Attribute
VC Voltage
Symbol
VVC
Analog Output
Startup
VC Current Limit
VC duration
VC Slew Rate
Conditions / Notes
Full temperature range
powertrain in burst mode
IVC
TVC
dVC/dt
DC state with TM Voltage +/- 0.5V. This is a high
impedance state.
RVC = 68Ω
Unit
V
V
350
mV
µA
10
mV/°C
100
ATM
TM Gain
Fault or
Standby
Symbol
V TM
0.0
mA
Conditions / Notes
Min
-100
Typ
Max
100
Unit
mA
Conditions / Notes
Min
13
Typ
Max
Unit
V
200
7
500
10
16
VC = 14 V, VIN > 20 V
RVC = 1kΩ
PRM® Regulator
Rev 1.1
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20
mA
ms
V/ µs
PRM48BH480T200B00
4.0 FUNCTIONAL BLOCK DIAGRAM
+Vin
Vcc
Vcc
3.3V
Linear
Regulator
Internal
Vcc
Regulator
PR Vout
PC
Cin
uC 8051
16V
9V
L
PR
8.2V
Cout
Q3
Q1
RE
+Vout
3.3V
-Vin
+Vout
Q4
Q2
-Vout
Output
Discharge
(OD)
Modulator
PR
93.3kW 100uA
Q
SET
Q
CLR
14V
VC
10ms
Fault Logic
Instant
latch
R
VTM Vc Start up pulse
TOFF
delay
S
2.5mA Min
Enable
Var. Vclamp
0.5m
A
Vcc RE
Latch after
120us
RE
3.3V
R
Vout
(OV)
5V
2mA max
3V
Vin
(OV, UV)
Vs
9V
0.01uF
Enable
PC
10uA
VPC_EN
TM
PC
3 V @ 27°C
Temperature
dependent voltage
source
Overtemperature
Protection
Current Limit
Overcurrent
Protection
Vref
(130°C)
PRM® Regulator
Rev 1.1
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800 927. 9474
VIF_IL
SG
2130W VIF_OC
IF
PRM48BH480T200B00
5.0 HIGH LEVEL FUNCTIONAL STATE DIAGRAM
Conditions that cause state transitions are shown along arrows. Sub-sequence activities listed inside the state bubbles.
Application of
Vin
PC HIGH
and
Toff expiry
Toff Timeout
PC: 90uA to HIGH Powertrain Stopped STANDBY
SEQUENCE
PC: 10uA to LOW
STARTUP
SEQUENCE
PC: 1.8mA to HIGH
Overtemp or Output OVP
PC HIGH
and
Ton expiry
Fault
removed
TBLNK
expiry
Ton timeout;
VC Pulse;
Powertrain Active
Delayed RE
BLANKING
PC: 1.8mA to HIGH
TBLNK Timeout
Powertrain Paused
Input OVP,
Input UVP,
or
OverCurrent Prot
SUSTAINED
OPERATION
PC: 1.8mA to HIGH
Powertrain Active
Short Circuit:
Vout < VSC_Vout
and
Vpr > VSC_Vpr
PC
falling
edge
Vout < 1 V
And
TSCR expiry
Short Removed: Vout > VSC_VOUTR or
Vpr < VSC_VPR_R
OUTPUT DISCHARGE
PC: pulsed 25mA drive
LOW
TSC
expiry
TSCR Timeout
Powertrain Stopped
IOD Output Discharge
PRM® Regulator
Rev 1.1
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Page 6 of 22
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800 927. 9474
SHORT
CIRCUIT
PC: 1.8mA to HIGH
TSC Timeout
Powertrain Active
PC
falling
edge
PRM48BH480T200B00
6.0 TIMING DIAGRAMS
Module Inputs are shown in blue; Module Outputs are shown in brown; Timing diagrams assumes the following:
 Single PRM (no array)
 VS powers error amplifier
 RE powers voltage reference and output current transducer
 IOUT is sensed, scaled, and fed back to IF pin such that IF = 2.00 V at full load
2
1
Start up with
1.2V/ms < dVIN/dt < maximum
VIN
OV
TOFF
3
4
Input OV
recovery
Quick OC Input OV
(t<TBLNK)
5
6
PC
disable
PC
release
7
8
Full load Load release and
applied Output OV (slow f/b)
TON
UV
18 V
Vpr_max
Input
TBLNK
PR
Vpr_min
t < TBLNK
VIF_OC
IF
VIF_IL
Input /
Output
PC
Vpc
TOFF
TON
TOFF
TPROT
TBLNK
Vpc_en
VC
Vvc
TVC
VOUT
TPROT
OV
1V
Output
RE
TVS_RE
TPC_RE
Vre_amb
TBLNK
Vvs_amb
VS
TM
OT
Vtm_amb
PRM® Regulator
Rev 1.1
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TPC_RE
TPC_RE
PRM48BH480T200B00
9
Start up with
minimum < dVIN/dt < 1.2V/ms
TOFF
VIN
OV
10
Output short
(Output Short fault
circuit
conditions satisfied)
(Output Short fault
timer expired)
11
12
13
Output Power
limit Protection
Current limit
event
Input UV
UV
18 V
Input
TBLNK
Vpr_max
PR
Vpr_min
VIF_OC
IF
VIF_IL
TSC
TSCR+TOFF
Output
PC
Vpc
Vpc_en
VC
Vvc
VOUT
OV
Input / Output
<TBLNK
Vsc_vpr
1V
RE
Vre_amb
Vvs_amb
VS
TM
OT
Vtm_amb
PRM® Regulator
Rev 1.1
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PRM48BH480T200B00
7.0 APPLICATIONS CHARACTERISTICS
The following figures present typical performance at TC = 25º C, unless otherwise noted. See associated figures for general
trend data.
No Load Power Dissipation vs. Line
Module Enabled - Nominal VOUT
1
Power Dissipation [W]
Power Dissipation [W]
6
No Load Power Dissipation vs. Line
Module Disabled, PC=Low
5
4
3
2
1
0
38
40
42
44
46
48
50
52
0.8
0.6
0.4
0.2
0
54
38
40
42
44
Input Voltage [V]
-40 ºC
TCASE:
25 ºC
46
48
50
52
54
Input Voltage [V]
100 ºC
-40 ºC
TCASE:
25 ºC
100 ºC
Figure 1 - No load power dissipation vs. VIN, module
enabled
Figure 2 - No load power dissipation vs. VIN, module
disabled
Efficiency & Power Dissipation
VOUT = 20 V
TCASE = -40 ºC
Efficiency & Power Dissipation
VOUT = 48 V
TCASE = -40 ºC
16
14
10
8
6
Efficiency [%]
12
4
2
0
0.5
1
1.5
2
2.5
3
3.5
4
98
96
94
92
90
88
86
84
82
80
78
76
74
72
70
4.5
14
12
10
8
6
4
2
0
0.5
1
1.5
Load Current [A]
VIN:
38
45
55
38
16
Power Dissipation
[W]
98
96
94
92
90
88
86
84
82
80
78
76
74
72
70
Power Dissipation
[W]
Efficiency [%]
2
2.5
3
3.5
4
4.5
Load Current [A]
45
55
Figure 3 – Total efficiency and power dissipation vs. VIN and
IOUT, VOUT = 20 V, TCASE = -40ºC
VIN:
38
45
55
38
45
55
Figure 4 – Total efficiency and power dissipation vs. VIN and
IOUT, VOUT = 48 V, TCASE = -40ºC
PRM® Regulator
Rev 1.1
vicorpower.com
Page 9 of 22
7/2015
800 927. 9474
PRM48BH480T200B00
98
96
94
92
90
88
86
84
82
80
78
76
74
72
70
16
14
10
8
6
Efficiency [%]
12
4
2
0
0.5
1
1.5
2
2.5
3
3.5
4
Efficiency & Power Dissipation
VOUT = 20 V
TCASE = 25 ºC
98
96
94
92
90
88
86
84
82
80
78
76
74
72
70
4.5
14
12
10
8
6
4
2
0
0.5
1
1.5
Load Current [A]
38
VIN:
45
55
16
Power Dissipation
[W]
Efficiency & Power Dissipation
VOUT = 55 V
TCASE = -40 ºC
Power Dissipation
[W]
Efficiency [%]
2
2.5
3
3.5
4
4.5
Load Current [A]
38
45
55
38
VIN:
Figure 5 – Total efficiency and power dissipation vs. VIN and
IOUT, VOUT = 55 V, TCASE = -40ºC
45
55
38
45
55
Figure 6 – Total efficiency and power dissipation vs. VIN and
IOUT, VOUT = 20 V, TCASE = 25ºC
98
96
94
92
90
88
86
84
82
80
78
76
74
72
70
16
14
10
8
6
Efficiency [%]
12
4
2
0
0.5
1
1.5
2
2.5
3
3.5
4
Efficiency & Power Dissipation
VOUT = 55 V
TCASE = 25 ºC
98
96
94
92
90
88
86
84
82
80
78
76
74
72
70
4.5
14
12
10
8
6
4
2
0
0.5
1
1.5
Load Current [A]
38
VIN:
45
55
16
Power Dissipation
[W]
Efficiency & Power Dissipation
VOUT = 48 V
TCASE = 25 ºC
Power Dissipation
[W]
Efficiency [%]
2
2.5
3
3.5
4
4.5
Load Current [A]
38
45
55
38
VIN:
Figure 7 – Total efficiency and power dissipation vs. VIN and
IOUT, VOUT = 48 V, TCASE = 25ºC
45
55
38
45
55
Figure 8 – Total efficiency and power dissipation vs. VIN and
IOUT, VOUT = 55 V, TCASE = 25ºC
98
96
94
92
90
88
86
84
82
80
78
76
74
72
70
16
14
10
8
6
Efficiency [%]
12
4
2
0
0.5
1
1.5
2
2.5
3
3.5
4
Efficiency & Power Dissipation
VOUT = 48 V
TCASE = 100 ºC
98
96
94
92
90
88
86
84
82
80
78
76
74
72
70
4.5
14
12
10
8
6
4
2
0
0.5
1
1.5
Load Current [A]
VIN:
38
45
55
38
16
Power Dissipation
[W]
Efficiency & Power Dissipation
VOUT = 20 V
TCASE = 100 ºC
Power Dissipation
[W]
Efficiency [%]
2
2.5
3
3.5
4
4.5
Load Current [A]
45
55
Figure 9 – Total efficiency and power dissipation vs. VIN and
IOUT, VOUT = 20 V, TCASE = 100ºC
VIN:
38
45
55
38
45
55
Figure 10 – Total efficiency and power dissipation vs. VIN
and IOUT, VOUT = 48 V, TCASE = 100ºC
PRM® Regulator
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16
6.5
14
12
10
8
6
5
4.5
4
2
0
0.5
1
1.5
2
2.5
3
3.5
4
6.12
-20
0
20
38
VIN:
45
55
38
45
IOUT:
55
Figure 11 – Total efficiency and power dissipation vs. VIN
and IOUT, VOUT = 55 V, TCASE = 100ºC
4.47
40
Temperature [ºC]
Load Current [A]
6.04
4.62
4.57
-40
4.5
6.21
5.5
4
6
VPR [V]
98
96
94
92
90
88
86
84
82
80
78
76
74
72
70
VPR vs. Case Temperature
VIN = 45 V; VOUT = 48 V
Power Dissipation
[W]
Efficiency [%]
Efficiency & Power Dissipation
VOUT = 55 V
TCASE = 100 ºC
60
80
2.08
100
4.17
Figure 12 – Typical control node voltage vs. TCASE, IOUT; VIN
= 45 V, VOUT = 48 V
Powertrain switching frequency and periodic
output charge vs. input voltage - Full load
fSW [kHz]
18
fsw
1000
16
975
14
950
12
925
10
900
8
875
6
µC
850
4
825
Total output charge
per switching cycle
[µC]
1025
2
0
800
38
40
42
44
46
48
50
52
54
56
Input Voltage [V]
Powertrain switching frequency and periodic
input charge vs. input voltage - Full load
18
14
950
12
925
10
900
8
875
6
µC
4
825
2
800
0
38
40
42
44
46
48
50
52
54
55
20
48
55
20
0.00
Rev 1.1
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80
0
10
15
20
25
30
35
40
45
50
Power
Figure 16 – DC Output Safe Operating Area
Page 11 of 22
120
40
Current
PRM® Regulator
160
Output Voltage [V]
48
200
2.08
1.04
5
Figure 15 – Powertrain switching frequency and periodic
input charge vs. VIN, VOUT; IOUT = 4.17 A
48
3.13
56
20
DC Safe Operating Area
4.17
Input Voltage [V]
VOUT
55
5.21
16
975
850
Total input charge per
switching cycle [µC]
fSW [kHz]
1000
48
55
60
Output Power [W]
fsw
20
Figure 14 – Powertrain switching frequency and periodic
output charge vs. VIN, VOUT; IOUT = 4.17 A
30ºC, VIN = 45 V, VOUT = 48 V, IOUT = 4.17 A, no external
capacitance.
1025
55
VOUT
Figure 13 – Typical output voltage ripple waveform, TCASE =
Output Current [A]
PRM48BH480T200B00
DC modulator gain and powertrain equivalent
output resistance vs. output current - VOUT = 55V
490
420
Gpr
-2
-4 -6
-8
280
210
140
req_out
70
-10
350
0
0
0.5
1
1.5
2
2.5
3
3.5
4
8
0
0.5
1
1.5
2
2.5
6
4
2
0
-2
-4
-6
4.5
Output Current [A]
38
VIN:
45
38
45
55
120
0
90
-2
-4
60
r eq_out
30
-6
0
0.5
1
1.5
2
2.5
3
3.5
45
45
35
28
21
14
7
0
4.5
55
4
38
55
38
45
55
Effective internal input (CIN_INT) and output
(COUT_INT) capacitance vs. applied voltage
3.5 3 2.5 2 1.5 1 0.5 4
0
0
4.5
5
10
15
20
45
25
30
35
40
45
50
55
Voltage [V]
Output Current [A]
38
VIN:
4
3.5
42
4.5
0
-8
150
Gpr
req_out [Ω ]
2
Effective capacitance [ µF]
G PR [dB]
3
49
180
4
38
VIN:
210
6
Figure 18 – Powertrain characteristics vs. IOUT;
Resistive load, VOUT = 20 V, various VIN
DC modulator gain and powertrain equivalent
output resistance vs. output current - VOUT = 48V
Gpr req_out Output Current [A]
55
Figure 17 – Powertrain characteristics vs. IOUT;
Resistive load, VOUT = 55 V, various VIN
req_out [Ω ]
0
G PR [dB]
2 G PR [dB]
4
req_out [Ω ]
DC modulator gain and powertrain equivalent
output resistance vs. output current - VOUT = 20V
55
Figure 19 – Powertrain characteristics vs. IOUT;
Resistive load, VOUT = 48 V, various VIN
Figure 20 – Effective internal input and output capacitance
vs. voltage – ceramic type
200
Output Power [W]
32
Typical min
180
80 60 40 20 0 100
2.5
24
Typical max
140
28
Nominal
160
120
Powertrain equivalent input resistance
vs. output current - VOUT = 55V
Output Power vs. VPR
VIN = 45V, VOUT = 48V, TC=25ºC
20
rIN [Ω]
4
3.5
4.0
4.5
5.0
5.5
6.0
6.5
12
8
3.0
16
0
7.0
0
0.5
1
PR Voltage [V]
2
2.5
3
3.5
4
4.5
Output Current [A]
VIN:
Figure 21 – Output Power vs. VPR; VIN = 45 V, VOUT = 48 V,
TCASE = 25ºC
1.5
38
45
55
Figure 22 – Magnitude of powertrain dynamic input
impedance vs. VIN, IOUT; VOUT = 55 V
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Powertrain equivalent input resistance
vs. output current - VOUT = 20V
Powertrain equivalent input resistance
vs. output current - VOUT = 48V
40
140 120 100
80
60 40 20 180
rIN [Ω]
160
0
0
35
30
25
rIN [Ω]
5
1
1.5
2
2.5
3
3.5
4
15
10
0.5
20
0
4.5
0
0.5
1
Output Current [A]
VIN:
38
45
1.5
2
2.5
3
3.5
4
4.5
Output Current [A]
VIN:
55
Figure 23 – Magnitude of powertrain dynamic input
impedance vs. VIN, IOUT; VOUT = 20 V
38
45
55
Figure 24 – Magnitude of powertrain dynamic input
impedance vs. VIN, IOUT; VOUT = 48 V
8.0 GENERAL CHARACTERISTICS
Specifications apply over all line and load conditions, TJ = 25 ºC and Output Voltage from 20 V to 55 V, unless otherwise
noted. Boldface specifications apply over the temperature range of -40 ºC < TJ < 125 ºC (T-grade).
Attribute
MECHANICAL
Length
Symbol
Conditions / Notes
Min
Typ
Max
Unit
L
21.8 / [0.86]
22.0 / [0.87]
22.3 / [0.88]
mm / [in]
Width
W
16.3 / [0.64]
16.5 / [0.65]
16.8 / [0.66]
mm / [in]
Height
H
6.48 / [0.255] 6.73 / [0.265] 6.98 / [0.275] mm / [in]
Volume
Vol
Weight
W
Lead Finish
ASSEMBLY
Peak Compressive Force Applied to
Case (Z-axis)
Storage Temperature
Nickel
Palladium
Gold
THERMAL
Operating and Storage Junction
Temperature
Operating Case Temperature
Thermal Capacity
No Heatsink
3
cm / [in ]
7
g
0.51
0.02
0.003
TJ
TC
Any operating condition
-40
-40
2.03
0.15
0.050
µm
125
100
ºC
ºC
Ws/ºC
5
-40
ESD Rating
3
5.33
125
Supported by J-Lead only
TST
ESDHBM
Human Body Model, "JEDEC JESD 22-A114C.01"
1000
ESDCDM
Charged Device Model, "JEDEC JESD 22-C101D"
400
3
2.44 / [0.15]
lbs
lbs / in
2
ºC
V
SOLDERING
Peak Temperature During Reflow
MSL 4 (Datecode 1528 and later)
Maximum Time Above [217] ºC
Peak Heating Rate During Reflow
Peak Cooling Rate Post Reflow
1.5
2.5
245
ºC
150
2
3
s
ºC / s
ºC / s
SAFETY and RELIABILITY
MTBF
Agency Approvals / Standards
Telcordia Issue 2 - Method I Case 1; Ground Benign, Controlled
2.51
MIL-HDBK-217Plus Parts Count - 25C Ground Benign, Stationary, Indoors / Computer Profile
C TUV US
CE Mark
ROHS 6 of 6
4.93
PRM® Regulator
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MHrs
PRM48BH480T200B00
9.0 PRODUCT OUTLINE DRAWING AND RECOMMENDED PCB FOOTPRINT
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10.1
PRODUCT DETAILS AND DESIGN GUIDELINES
10.2
Control pins description and characteristics
highest at full load and lowest at minimum load. Figure 25
shows a reference AC small-signal model.
Control node (PR) is the input to the control node which
determines the powertrain timing and ultimately the
module output power (Figure 21). An internal 0.5mA
current sink is always active. The bi-directional buffer
between PR and the control node has two states. In
normal operation, PR will be above the 0.79 V switching
threshold, and will drive the control node through the
buffer. An internal 7.4 V clamp determines the maximum
output power that can be requested of the modulator.
When PR falls below 0.79 V, the converter will stop
switching. An internal circuit clamps the modulator input
control node to 0.79 V, and a buffer will source up to
2.5 mA out of the pin at that clamp level. For this reason,
the output impedance of the amplifier driving PR must be
taken into account. A rail-to-rail operational amplifier with
low output impedance is always recommended.
The powertrain small signal (plant) response consists of a
single pole determined by the load resistance, the
powertrain equivalent output resistance, and the total
output capacitance (internal and external to the module).
Both the modulator gain and the equivalent output
resistance vary as a function of line, load and output
voltage, as shown in Figures 17, 18 and 19. As the load
increases, the powertrain pole moves to higher frequency.
As a result, the closed loop crossover frequency will be the
Current feedback (IF) is the input for the module output
overcurrent protection and current limit features (see
functional block diagram in section 4.0). A voltage
proportional to the powertrain output current must be
applied to IF in order for overcurrent protection to operate
properly.
If the IF voltage exceeds the IF pin’s overcurrent
protection threshold, the powertrain will stop switching. If
the IF voltage falls below the overcurrent protection
threshold within TBLANK time, then the powertrain will
immediately resumes switching. Otherwise a fault is
latched.
The current limit threshold for the IF pin is set lower than
the protection threshold. When the IF pin average voltage
exceeds the current limit threshold, an internal integrator
will activate a clamp amplifier
which overrides the
modulator input maximum level. This causes the
powertrain to maintain a constant output current.
The bandwidth of this current limit integrator is significantly
slower than that of the PR control node input. Therefore
this current limit can not be used in lieu of properly
compensating the (external) PR control loop to avoid
exceeding maximum current or power ratings for the
device.
If the IF pin is not driven, it must be resistively terminated
to SG. A 1 kΩ resistor to SG is recommended in this case.
+
VIN
CIN_INT
rEQ_IN
+
VPR
+
VPR · GPR
r
RPR
IPR_Low COUT_INT
EQ_OUT
-
-
Figure 25 – PRM48BH480T200B00 AC small signal model
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Signal Ground (SG) pin provides a Kelvin connection to
the PRM’s internal signal ground. It should be used as the
reference for PR, TM, IF, and should return all PC, VS and
RE pin currents. In array configurations with common
ground control circuits, a series resistor (~1 Ω) is
recommended in order to decouple power and signal
current returns.
VTM Control (VC) pin supplies an initial VCC voltage to
downstream VTMs, enabling them and synchronizing their
startup with the PRM. The VCC voltage is a pulse, typically
10 ms duration at 14 V.
If VC is not loaded by a VTM, it must be terminated with a
1 kΩ resistor to –VOUT.
Primary Control (PC) is both an input and an output. It
can provide the following features:
• Delayed start: upon application of voltage (>UVLO) to the
module power input and after TOFF, the PC pin will source
a constant 90 µA current.
• Output disable: PC may be pulled down externally in
order to disable the module. Pull down resistance should
be less than 300 Ω to SG.
• Fault detection flag: The PC 5 V voltage source is
internally turned off when a fault condition is latched. Note
that aside from the Short Circuit fault condition, PC does
not have significant current sinking capability. Therefore in
the case of an array of PRMs with interconnected PC pins,
PC does not in general reflect the fault state of all PRMs.
The common PC line will not disable neighboring modules
when a fault is detected except for a latched Output Short
Circuit fault. Conversely any unit in the array latching a
Short Circuit fault will disable the array for TSCR.
Temperature Monitor (TM) pin outputs a voltage
proportional to the absolute temperature of the converter
analog control IC. It can be used to accomplish the
following functions:
• Monitor the control IC temperature: The gain and setpoint
of TM are such that the temperature, in Kelvin, of the PRM
controller IC is equal to the voltage on the TM pin scaled
by 100. (i.e. 3.0 V = 300 K = 27 ºC).
• Closed loop thermal management at the system level
(e.g. variable speed fans or coolant flow)
• Fault detection flag: The TM voltage source is turned off
as soon as a fault is detected. For system monitoring
purposes (microcontroller interface) faults are detected on
falling edges of TM.
10.2
The PRM48BH480T200B00 is an intelligent powertrain
module designed to fully exploit external output voltage
feedback and current sensing sub-circuits. These two
external circuits are illustrated in Figure 26, which shows
an example of the PRM in a standalone application with
local voltage feedback and high side current sensing.
In general, these circuits include a precision voltage
reference, an operational amplifier which provides closed
loop feedback compensation, and a high side current
sense circuit which includes a shunt and current sense IC.
Voltage Source (VS) pin outputs a gated (e.g. mirrors PC
status), non-isolated, regulated 9 V, 5 mA voltage source.
It can be used to power external control circuitry; it always
leads RE.
The following design procedures refer to the circuit shown
in Figure 26.
10.2.1 Setting the output voltage level
The output voltage setpoint is a function of the voltage
reference and the output voltage sense ratio. With
reference to Fig. 26, R1 and R2 form the output voltage
sensing divider which provides the scaled output voltage
to the negative input of the error amplifier; a dedicated
reference IC provides the reference voltage to the positive
input of the error amplifier. Under normal operation, the
error amplifier will keep the voltages at the inverting and
non-inverting inputs equal, and therefore the output
voltage is defined by:
VOUT = V ref ⋅
Reference Enable (RE) pin outputs a regulated 3.3 V,
8 mA voltage source. It is enabled only after successful
startup of the PRM powertrain (see chapters 5.0 and 6.0.)
RE is intended to power the output current transducer and
also the voltage reference for the control loop. Powering
the reference generator with RE helps provide a controlled
startup, since the output voltage of the system is able to
track the reference level as it comes up.
Control circuit requirements and design procedure
R1 + R2
R2
Note that the component R1 will also factor into the
compensation as described in a later section.
It is important to apply proper slew rate to the reference
voltage rise when the control loop is initially enabled. The
recommended range for reference rise time is 1 ms to 9
ms. The lower rise time limit will ensure optimized
modulator timing performance during startup, and to allow
the current limit feature (through IF pin) to fully protect the
device during power-up. The upper rise time limit is
needed to guarantee a sufficient factorized bus voltage is
provided to any downstream VTM input before the end of
the VC pulse.
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10.2.2 Setting the output current limit and overcurrent
protection level
 Internal output capacitance: see Figure 20
 External output capacitance value
In the case of ceramic capacitors, the ESR can be
considered low enough to push the associated zero well
above the frequency of interest. Applications with high
ESR capacitor may require a different type of
compensation, or cascade control.
The system poles and zeros of the closed loop can then
be defined as follows:
The current limit and overcurrent protection set points are
linked, and scale together against the current sense shunt,
and the gain of the current sense amplifier. The output of
the current sense IC provides the IF voltage which has
VIF_IL and VIF_OC thresholds for the two functions
respectively. The set points are therefore defined by:
I IL =
and
 Powertrain pole, assuming the external capacitor
ESR can be neglected:
VIF _ IL
RS ⋅ G CS
RCOUT _ EXT <<
I OC =
VIF _ OC
RS ⋅ G CS
rEQ _ OUT ⋅ RLOAD
rEQ _ OUT + RLOAD
 Main pole frequency:
where GCS is the gain of the current sense amplifier.
P
10.2.3 Control loop compensation requirements
In order to properly compensate the control loop, all
components which contribute to the closed loop frequency
response should be identified and understood. Figure 25
shows the AC small signal model for the module.
Modulator DC transconductance gain (GPR) and powertrain
equivalent resistance (rEQ_OUT) are shown.
These
modeling parameters will support a design cut-off
frequency up to 50 kHz.
Standard Bode analysis should be used for calculating the
error amplifier compensation and analyzing the closed
loop stability. The recommended stability criteria are as
follows:
1) Phase Margin > 45º : for the closed loop response, the
phase should be greater than 45º where the gain crosses
0dB.
2) Gain Margin > 10dB : The closed loop gain should be
lower than -10dB where the phase crosses 0º.
3) Gain Slope = -20dB / decade : The closed loop gain
should have a slope of -20dB / decade at the crossover
frequency.
The compensation characteristics must be selected to
meet these stability criteria. Refer to Figure 27 for a local
sense, voltage-mode control example based on the
configuration in Figure 26. In this example, it is assumed
that the maximum crossover frequency (FCMAX) has been
selected to occur between B and C. Type-2 compensation
(Curve IJKL) is sufficient in this case.
The following data must be gathered in order to proceed:
 Modulator Gain GPR: See Figures 17, 18, 19
 Powertrain equivalent resistance rEQ: See Figures
17, 18, 19
1
F ≈
2 π⋅
rEQ _ OUT · RLOAD
rEQ _ OUT + RLOAD
 Compensation
G MB = 20 log
R
Mid-Band
OUT
INT
+ COUT
[1]
R1
Zero:
1
F =
Gain:
3
 Compensation
· (C [2]
2 π⋅ R 3 ⋅ C1
Z1
 Compensation
Pole:
1 FP 2 =
⋅C
2 π⋅ R3 ⋅ C1 2
C1 + C2
and for FP2>>FZ1 (C1 + C2 ≈ C1):
F
P2
≈
1
2π ⋅ R3 ⋅ C2
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[3]
EXT
)
PRM48BH480T200B00
10.2.4 Midband
(R1,R3):
Gain
Design
10.2.5 Compensation Zero Design (C1):
With reference to Figure 27: curve ABC is the:
 minimum output voltage in the application
 maximum input voltage expected in the application
 maximum load
PRM open loop response, and is where the maximum
crossover frequency occurs. In order for the maximum
crossover frequency to occur at the design choice FCMAX,
the compensation gain must be equal and opposite of the
powertrain gain at this frequency. For stability purposes,
the compensation should be in the Mid-band (J-K) at the
crossover. Using Equation [1], the mid-band gain can be
selected appropriately.
With reference to Figure 27: curve EFG is the:
 maximum output voltage in the application
 minimum input voltage expected in the application
 minimum load in the application
PRM open loop response, and is where the minimum
crossover frequency FCMIN occurs. Based on stability
criteria, the compensation must be in the mid-band at the
minimum crossover frequency, therefore FCMIN will occur
where EFG is equal and opposite of GMB. C1 can be
selected using Equation [2] so that FZ1 occurs prior to
FCMIN.
C2
C1
R3
+
Vref
R2
R1
F1
+IN
VS
PR
RS
+OUT
CIN_EXT
CIN_INT
PRM
COUT_EXT
COUT_INT
-IN
IF RE
SG
-OUT
Vref I sense
IC
Vref IC
Figure 26 – Control circuit example
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Open Loop Gain vs. Frequency
80
60
I Application's op-amp G·BW
Compensation Gain
40
Gain (dB)
20
F
E
PRM Open Loop Min Load
B
A
PRM Open Loop Max Load
J
K
FCMIN
0
L
FCMAX
-20
C
G
-40
Frequency, Log scale
(y-intercept is application specific)
Figure 27 – Reference asymptotic Bode plot for the considered system
10.2.6
High Frequency Pole Design (C2):
Using Equation [3], C2 should be selected so that FP2 is at
least one decade above FCMAX and prior to the gain
bandwidth product of the operational amplifier (10 MHz for
this example). For applications with a higher desired
crossover frequency the use of a high gain bandwidth
product amplifier may be necessary to ensure that the real
pole can be set at least one decade above the maximum
crossover frequency.
based on the ratio of the “kick” to “droop” (as defined in
Fig. 28).
k
Vout
d
10.2.7 Verifying
Stability:
The preferred method for verifying stability is to use a
network analyzer, measuring the closed loop response
across various lines and load conditions.
In the absence of a network analyzer, a load step transient
response can be used in order to estimate stability.
Figure 28 illustrates an example of a load step response.
Equation [4] can be used to predict the phase margin
time
Iou
t
time
Figure 28 – load step response example and “droop”
vs. “kick” definition
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10.3
k2
  
ln

 m 100
 d2 
k
+ 2
ln 


d 
Burst
Operation:
Figure 20 provides the effective internal capacitance of the
module. A conservative estimate of input and output peakpeak voltage ripple at nominal line and trim is provided by
equation [5]:
[4]
ΔV =
Mode
QTO T ­
CINT
I
FL
⋅ 0.4 f SW + CEXT
[5]
At light loads, the PRM will operate in a burst mode due to
minimum timing constraints. An example burst operation
waveform is illustrated in Figure 29.
For very light loads, and also for higher input voltages, the
minimum time power switching cycle from the powertrain
will exceed the power required by the load. In this case the
external error amplifier will periodically drive PR below the
switching threshold in order to maintain regulation.
Switching will cease momentarily until the error amplifier
once again drives PR voltage above the threshold.
QTOT is the total input (Fig. 15) or output (Fig. 14) charge
per switching cycle at full load, while CINT is the module
internal effective capacitance at the considered voltage
(Fig. 20) and CEXT is the external effective capacitance at
the considered voltage.
10.5
Input filter stability
The PRM can provide very high dynamic transients. It is
therefore very important to verify that the voltage supply
source as well as the interconnecting line are stable and
do not oscillate. For this purpose, the converter dynamic
input impedance magnitude
rEQ _ IN
is provided in Figures
22, 23, 24. It is recommended to provide adequate design
margin with respect to the stability conditions illustrated in
10.5.1 and 10.5.2.
10.5.1 Inductive source and local, external input
decoupling capacitance with negligible ESR (i.e.: ceramic
type)
Figure 29 – light load burst mode of operation
Note that during the bursts of switching, the powertrain
frequency is constant, but the number of pulses as well as
the time between bursts is variable. The variability
depends on many factors including input voltage, output
voltages, load impedance, and external error amplifier
output impedance.
In burst mode, the gain of the PR input to the plant which
is modeled in the previous sections is time varying.
Therefore the small signal analysis can not be directly
applied to burst mode operation.
The voltage source impedance can be modeled as a
series RlineLline circuit. The high performance ceramic
decoupling capacitors will not significantly damp the
network because of their low ESR; therefore in order to
guarantee stability the following conditions must be
verified:
Rline >
(C
Lline
+C
IN INT
Rline << rEQ _ IN
IN EXT
)⋅ r
[6]
EQ IN
[7]
10.4
Input and Output filter design
Figures 14 and 15 provide the total input and output
charge per cycle, as well as switching frequency, of the
PRM at full load under various input and output voltages
conditions.
It is critical that the line source impedance be at least an
octave lower than the converter’s dynamic input
resistance, [7]. However, Rline cannot be made arbitrarily
low otherwise equation [6] is violated and the system will
show instability, due to under-damped RLC input network.
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10.5.2 Inductive source and local, external input
decoupling capacitance with significant RCIN_EXT ESR (i.e.:
electrolytic type)
In order to simplify the analysis in this case, the voltage
source impedance can be modeled as a simple inductor
Lline. Notice that, the high performance ceramic capacitors
CIN_INT within the PRM should be included in the external
electrolytic capacitance value for this purpose. The
stability criteria will be
rEQ _ IN > RC
[8]
IN _ EXT
Lline
C IN _ EXT ⋅ RC <r
temperature differences among PRMs, Vin
variations, and error terms in the buffering of the
error amplifier output to the PR pins.
 Control loop compensation procedures above will
hold for an array, in general, although many
parameters must be scaled against the number of
PRMs in the system.
[9]
IN _ EXT
10.6
Arrays
Up to ten PRMs of the same type may be placed in
parallel to expand the power capacity of the system. The
following high-level guidelines must be followed in order
for the resultant system to start up and operate properly,
and to avoid overstress or exceeding any absolute
maximum ratings.
 –IN pins of all PRMs must be connected together.
Both inductance and resistance from the common
power source to each PRM should be minimized,
and matched.
 Input voltage to all PRMs must be the same.
Independent
fuses
for
each
PRM
are
recommended.
 PC pins must be connected together for
synchronization and proper fault response.
 Reference supply to the control loop voltage
reference and current sense circuitry must be
enabled when all modules’ RE pins have reached
their operational voltage levels.
 There must be one single external voltage control
loop. The control loop must drive each PR pin
relative to each module’s SG pin, and the local PR
voltage must be the same across all modules.
 Each PRM must have its own local current shunt
and current sense circuitry to drive its IF pin.
 The number of PRMs required to achieve a given
array capacity must consider all sources of
mismatch to avoid overstress of any PRM in the
array. Imbalances in sharing are not only due to
current sharing accuracy specifications, but also
10.7
Input Fuse Recommendations
A fuse should be incorporated at the input to each PRM, in
series with the +IN pin. A 10 A or smaller input fuse
2®
®
451/453 Series, or equivalent) is
(Littelfuse NANO
required to safety agency conditions of acceptability.
Always ascertain and observe the safety, regulatory, or
other agency specifications that apply to your specific
application.
EQ _ IN
Equation [9] shows that if the aggregate ESR is too small
– for example by using very high quality input capacitors
(CIN_EXT) – the system will be under-damped and may even
become destabilized. Again, an octave of design margin in
satisfying [8] should be considered the minimum.
Please contact Vicor Applications for assistance.
10.8
Layout considerations
Application Note AN:005 details board layout using
VI Chip components. Additional consideration must be
given to the external control circuit components.
The current sense shunt signal voltage is highly sensitive
to noise. As such, current sensing circuitry should be
located close to the shunt to minimize the length of the
sense signals. A Kelvined connection at the shunt is
recommended for best results.
The control signal from a remote voltage sense circuit to
the PRM should be shielded. Avoid routing this, or other
control signals directly underneath the PRM, if possible.
Components that tie directly to the PRM should be located
close to their respective pins. It is also critical that all
control components be referenced to SG, and that SG not
be tied to any other ground in the system, including –IN or
–OUT of the PRM.
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Warranty
Vicor products are guaranteed for two years from date of shipment against defects in material or workmanship when in
normal use and service. This warranty does not extend to products subjected to misuse, accident, or improper application
or maintenance. Vicor shall not be liable for collateral or consequential damage. This warranty is extended to the original
purchaser only.
EXCEPT FOR THE FOREGOING EXPRESS WARRANTY, VICOR MAKES NO WARRANTY, EXPRESS OR IMPLIED,
INCLUDING, BUT NOT LIMITED TO, THE WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR
PURPOSE.
Vicor will repair or replace defective products in accordance with its own best judgment. For service under this warranty,
the buyer must contact Vicor to obtain a Return Material Authorization (RMA) number and shipping instructions. Products
returned without prior authorization will be returned to the buyer. The buyer will pay all charges incurred in returning the
product to the factory. Vicor will pay all reshipment charges if the product was defective within the terms of this warranty.
Information published by Vicor has been carefully checked and is believed to be accurate; however, no responsibility is
assumed for inaccuracies. Vicor reserves the right to make changes to any products without further notice to improve
reliability, function, or design. Vicor does not assume any liability arising out of the application or use of any product or
circuit; neither does it convey any license under its patent rights nor the rights of others. Vicor general policy does not
recommend the use of its components in life support applications wherein a failure or malfunction may directly threaten
life or injury. Per Vicor Terms and Conditions of Sale, the user of Vicor components in life support applications assumes
all risks of such use and indemnifies Vicor against all damages.
Vicor’s comprehensive line of power solutions includes high density AC-DC and DC-DC
modules and accessory components, fully configurable AC-DC and DC-DC power supplies,
and complete custom power systems.
Information furnished by Vicor is believed to be accurate and reliable. However, no responsibility is assumed by Vicor for
its use. Vicor components are not designed to be used in applications, such as life support systems, wherein a failure or
malfunction could result in injury or death. All sales are subject to Vicor’s Terms and Conditions of Sale, which are
available upon request.
Specifications are subject to change without notice.
Intellectual Property Notice
Vicor and its subsidiaries own Intellectual Property (including issued U.S. and Foreign Patents and pending patent
applications) relating to the products described in this data sheet. Interested parties should contact Vicor's Intellectual
Property Department.
The products described on this data sheet are protected by the following U.S. Patents Numbers:
5,945,130; 6,403,009; 6,710,257; 6,911,848; 6,930,893; 6,934,166; 6,940,013; 6,969,909; 7,038,917;
7,145,186; 7,166,898; 7,187,263; 7,202,646; 7,361,844; D496,906; D505,114; D506,438; D509,472; and for
use under 6,975,098 and 6,984,965.
Vicor Corporation
25 Frontage Road
Andover, MA, USA 01810
Tel: 800-735-6200
Fax: 978-475-6715
email
Customer Service: [email protected]
Technical Support: [email protected]
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