
10-6 Sensors and Sensor Technology
the transistor can be controlled by a pulse width modulator (PWM) or by a pulse frequency modulator
(PFM). e traditional PWM used in switching converters is not the most suitable solution in low-power
ap
plications
. A pe
riodic
sw
itching
se
quence
ho
lds
th
e
tr
ansistor
in on st
ate
du
ring
a po
rtion
of th
e
se
quence
pe
riod,
ca
lled
du
ty cycle
. e vo
ltage
of th
e
PV pa
nel
is ad
justed
by me
ans
of th
e
du
ty cycle
. As th
e
tr
ansistor
is co
ntinuously
sw
itching,
th
e
re
sulting
po
wer
co
nsumption
is to
o
hi
gh
fo
r
lo
w-power
PV pa
nels
(<
1W)
.
In
stead,
PF
M
ca
n
be us
ed
to fu
rther
re
duce
po
wer
co
nsumption
. e co
nverter
re
mains
in
active ...