TDA7272A Datasheet, PDF (13/16 Pages) STMicroelectronics – HIGH PERFORMANCE MOTOR SPEED REGULATOR

Figure 23: P.C. board and components layout of the circuits of Figg. 20, 21, 22.
TDA7272A
A
APPLICATION SUGGESTION (Fig. 20,21,22) - (For a 2000 r.p.m. 3 pole DC motor with R_M = 16Ω)
Components
R_S1
RS2
R_L; C_L
C_D
R_T; C_T
RP1; RP2
C_F
RA; CA
Recommended
value
1Ω
1.5Ω
22KΩ - 68nF
68nF
15KΩ - 47nF
47KΩ trim.
Polyester 100nF
220KΩ - 220nF
Purpose
Current sensing
tacho loop.
Current sensing
V/I loop.
Spike filtering.
Pulse transf.
Current source
programming to
obtain a 50%
duty cycle
Set of speed.
Optimization of
integrator ripple
and loop
response time.
Fast response
with no
overshoot.
If larger
Instability may
occur.
Slow V/I
regulator
response.
If smaller
Tacho loop do
not regulate
Motor regulator;
undercompens.
High output
ripple.
Low speed.
High speed
Lower ripple,
slower tacho
regulator
response.
Higher ripple,
faster response.
Depending on electrmechanical
system.
Allowed range
Min.
Max.
0
0
RMOT/9
33nF
67KΩ
100nF
30KW
0
10nF
470nF
10nF 470nF
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