Data Sheet

Specifications on this catalog are for reference only, as they are subject to change without notice.
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Linearity
The term “linearity” implies that the real law obtained from plotting angular position vs voltage output is compared
with a straight line.
Independent linearity (LN)
It is the maximum vertical deviation of the real law from the straight reference line chosen to best minimize the distance from the real line
in any position.
It is expressed as a percentage of the total voltage applied.
In the graph below, “K” would be the maximum independent linearity and “k” the line with which the real law is compared.
Absolute Linearity (LA)
It is the maximum vertical deviation of the real law from the straight reference line that runs through specified minimum and maximum points.
These points would be zero and 100% of the maximum applied voltage.
In the graph below, “H” would be the maximum absolute linearity of the real law and “h” the theoretical line with which the real line is
compared. When some customers are looking for correspondence of angle and value, this is the concept to consider.
Output ratio
Vo
Vi
Effective electrical angle: 230º
Theorical electrical angle: 245º
k
h
K
H
Initial
angle
tolerance
H: Absolute linearity.
Theoretical line: line h is the reference for absolute linearity.
K: Independent linearity.
Line k is chosen to minimize deviation.
Real law.
Reflow soldering SMDManual soldering
Soldering conditions (Lead free, RoHS compliant)*
(*) For other information on soldering conditions, please, contact us.
Soldering tools of 20W max.
Recommended
soldering
conditions
Flow (wave) soldering
Maximum temperature of soldering tools: 280ºC
Time: 3 s. max.
Preheating temperature: Max 150ºC; 60-90 s
Temperature Ramp-up: 2-3ºC / s.
Over 220ºC:<40 s.
Solder temperature: 240ºC for 5 ± 1 s.
Besides recommended conditions,
ACP SMD potentiometers have successfully
passed tests at 260ºC (air temp) for 10s.
Recommended Alloy: SnAgCu
Preheating stage: Max 100ºC; 30-60 s.
Temperature Ramp-up:1.2-2.5ºC/s.
Max. wave temp.: 260ºC for 4s.,
(245ºC recommended)
Time within +0º-10ºC of peak: 10s.
Cooling rate: 5ºC/s.
The standard taper is linear (A). Log (B) and Antilog (C) tapers are also available, as well as special tapers according
to customer’s specifications. For example, a special taper can be matched with a potentiometer with detents (click effect), to guarantee
a value in a specific position – see bellow.-
ACP can also provide with tapers with different slopes, with areas with constant value or jumps, according to customer’s specifications.
Special tapers can be combined with physical detents to match the areas where the customer wants to guarantee a constant value with
a particular angular position. This is particularly suitable in applications which can benefit from a feeling of maintained control over the
position, for example, regulation of temperature or speed.
% Resistance or
Vo
Vi
Rotation angle 
REGULAR TAPERS SPECIAL TAPERS
Variation laws
- Tapers -
% Resistance
100
75
50
25
0
0 25 50 10075
Antilog (C)
Linear (A)
Log (B)
% Rotation angle
θ
A (Linear)
B (Log)
C (Antilog)