PAF600F280-28 TDK Corporation, PAF600F280-28 Datasheet - Page 28

• Manufacturer Part Number: PAF600F280-28
• Description: 28V@21.5A
• Manufacturer: TDK Corporation

PAF
B-120
PAF
Output Voltage Adjustment by external resistor or by
variable resistor
Resistor values, as well as, connecting methods for ex-
ternal resistor (R2) and external variable resistor (VR) are
described below.
In this case, using VR as remote programming resistor, re-
mote programming of output voltage can be possible.
Also, be sure to connect remote programming resistor be-
tween +S terminal and +V terminal.
Table2-1 Values of External Resistor and Variable Resistor
3.3V, 5V：
12V, 28V
PAF500･600F48：
PAF700F48：
Fig.2-2 Example Connection of External Resistor
R2
VR
R2
VR
＋S
＋V
−V
−S
TRIM
External Resistor: below±5% Tolerance
Variable Resistor: below±20% Tolerance
External Resistor: below±5% Tolerance
Variable Resistor: below±20% Tolerance
120
110
100
90
Table2-2 Values of External Resistor and
500F48, 600F48, 700F48
Fig.2-1 Limit of Input Voltage
3.3V
3.3V
3.9k
10k
20k
2k
35
Variable Resistor (±10% Variable )
R2
VR
36
PAF500・600F48-12V,28V Model
PAF500・600F48-12V, 28V Model
Input Voltage （VDC）
40
below 1% Remain
below 1% Remain
6.8k
10k
43k
PAF700F48-12V,28V Model
PAF700F48-12V, 28V Model
5V
5V
2k
-40% to +20% Variable
-40% to +10% Variable
-40% to +15% Variable
3.3V,5V Model
3.3V, 5V Model
45
6.8k
12V
12V
20k
43k
5k
50
Load
＋
−
Unit： ［Ω］
55
Unit ： ［Ω］
6.8 k
28V
28V
50k
43k
10k
Output Voltage Adjustment by applying external voltage
By applying external voltage at the TRIM terminal, output
voltage can be adjusted within the same output voltage
adjustment range as the output voltage adjustment by
external resistor or variable resistor. For this case, output
voltage can be determined by the formula shown below.
For applications other than the above, refer to the trim cir-
cuit below and determine external circuit and component
values.
3 Maximum Ripple and Noise
Measured value according to the specified methods based
on JEITA-9141 (Clause 7.12 and clause 7.13) which is
described in the following.
Connect according to fig.3-1and measure. Connect capaci-
tors (C2: ceramic capacitor 10μF, C3: refer to table 1-1
for electrolytic capacitor values) at 50mm distance from
the output terminals. Measure at ceramic capacitor (C2)
leads as shown in fig. 3-1using coaxial cable with JEITA
attachment. Use oscilloscope with 100MHz frequency
bandwidth or equivalent.
Take note that output ripple voltage and output spike noise
may vary depending on PCB wiring design.
Generally, output ripple voltage and output spike noise can
be reduced by increasing capacitance value of external
capacitor.
Fig.2-3 Output Voltage Adjustment by applying external voltage
＋V
−V
Output Voltage = TRIM Terminal Voltage
＋S
＋V
−V
−S
TRIM
Fig.3-1 Measurement of Maximum Output
Fig.2-4 TRIM Circuit (For the Reference)
1.225V
Reference
Voltage
50mm
Error Amplifier
C2
7.32k
External
Voltage
+
Ω
−
＋
・All specifications are subject to change without notice.
C3
Ripple & Noise
1.5m 50Ω
Coaxial Cable
32.4k Ω
×Nominal Output Voltage
As short as possible
Load
1kΩ
C
R
Oscilloscope
JEITA Attachment
R:50Ω
C:4700pF
Load
＋
−
＋S
−S
TRIM