P024F048T12AL_15 Datasheet, PDF (9/14 Pages) Vicor Corporation – Non-isolated Regulator

Application Information
P024F048T12AL
V_IN
Regulator
VC
VH
0.01 µF
PC
TM
SC
SG
IL
OS
NC
NC ^ROS
10 kΩ
PR
PRM^®-AL
CD
R_CD
+In
+Out
–In
–Out
V_F =
VL
K
+
(I_L•_Ro)
K
0.4 µH
10 Ω
Current Multiplier
+Out
+In
L
+Out
TM
VC
VTM^®
PC
– Out
O
A
K
D
– In _{Ro – Out}
Figure 16 — Adaptive Loop compensation with soft start using the SC port.
Output Voltage Setting with Adaptive Loop
The equations for calculating R_OS and R_CD to set a VTM output
voltage are:
93100
R_OS =
( ^{VL • 0.8395} ) – 1
(1)
K
R_CD =
91238 _{+ 1}
(2)
R_OS
V_L = Desired load voltage
V_OUT = VTM output voltage
K = VTM transformation ratio
(available from appropriate VTM data sheet)
V_f = PRM output voltage, the Factorized Bus (see Figure 16)
R_O = VTM output resistance
(available from appropriate VTM data sheet)
I_L = Load Current
(actual current delivered to the load)
Output Voltage Trimming (optional)
After setting the output voltage from the procedure above the output
may be margined down (26 Vf min) by a resistor from SC-SG using
this formula:
R_dΩ = ^{10000 Vfd}
V_fs - V_fd
Where V_fd is the desired factorized bus and V_fs is the set factorized bus.
A low voltage source can be applied to the SC port to margin the load
voltage in proportion to the SC reference voltage.
An external capacitor can be added to the SC port as shown in Figure 16
to control the output voltage slew rate for soft start.
Nominal Vout
Range (Vdc)
0.8 ^↔ 1.6
1.1 ^↔ 2.2
1.6 ^↔ 3.3
2.2 ^↔ 4.4
3.3 ^↔ 6.6
4.3 ^↔ 8.8
6.5 ^↔ 13.4
8.7 ^↔ 17.9
13.0 ^↔ 26.9
17.4 ^↔ 36.0
26.0 ^↔ 54.0
VTM
K Factor
1/32
1/24
1/16
1/12
1/8
1/6
1/4
1/3
1/2
2/3
1
Table 2 — 048 input series VTM K factor selection guide
PRM^® Regulator
Page 9 of 14
Rev 3.2
07/2015
vicorpower.com
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