uba20271 NXP Semiconductors, uba20271 Datasheet - Page 10

• Manufacturer Part Number: uba20271
• Description: 350 V And 600 V Power Ics For Dimmable Compact Fluorescent Lamps
• Manufacturer: NXP Semiconductors

NXP Semiconductors
UBA20271_UBA20272
Product data sheet
Fig 7.
(1) Temp > T
(2) Temp < T
(3) NOT (Boost OR Boost transition)
(4) Temp > T
(5) Boost_Transition timer ended OR V
Boost and burn state machine
burn select
7.1.7 Hold state
(1)
burn
j(bp)bst
j(bp)bst
j(end)bst
10
00
OR Boost_Disable
AND NOT Boost_Disable
V
internal current output of the OTA is transferred via an integrator on the CI pin to the input
of the Voltage Controlled Oscillator (VCO). The VCO regulates the frequency and as a
result, the lamp current.
The hold state is a special state to reduce lamp flicker at deep dim levels, on or near dim
and ignition threshold level. See
The hold state is entered following:
A repeated aborted preheat or ignition cycle due to a drop in DCI voltage that is lower than
V
ignition state does not increment the ignition attempt counter. The UBA20271/2 enters the
hold state only delaying a new preheat cycle by the same time delay and mechanism. As
shown in
OR Boost timer ended OR (Boost_ratio = 1.5 AND V
i(CSI)
th(start)DCI
(66 % level)
•
•
•
a failed ignition attempt
or when the low supply voltage V
state
or when V
= V
otp(CSI)
temp < (T
Figure 5
 V
temp > (T
DCI
th(hys)DCI
j(otp)
(2)
(5)
DCI
All information provided in this document is subject to legal disclaimers.
350 V and 600 V Power ICs for dimmable compact fluorescent lamps
< V
- T
j(otp)
< V
hold state retention time.
j(otp)hys
V
i(CSI)
th(bst)DCI
th(start)DCI
Rev. 2 — 8 September 2011
(100 % level)
or a drop in supply voltage that is lower than V
= V
clamp(CSI)
 V
BOOST AND BURN
boost timer running
 V
th(bst)hys(DCI)
boost transition
STATES
Figure
th(hys)DCI
boost
01
11
DD
(4)
3.
OR Temp > T
is lower than V
DCI
in the ignition or preheat state
< V
Boost_ratio = 1
th(bst)DCI
j(otp)
V
i(DCI)
- V
DD(stop)
> V
th(bst)hys(DCI)
th(bst)DCI
(3)
in the ignition or preheat
UBA20271/2
Boost_ratio = 1.5
AND boost
)
DD(stop)
© NXP B.V. 2011. All rights reserved.
001aam668
in preheat or
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