uba20261 NXP Semiconductors, uba20261 Datasheet - Page 10

• Manufacturer Part Number: uba20261
• Description: 600 V And 350 V Power Ic For Step Dimmable Cfls
• Manufacturer: NXP Semiconductors

NXP Semiconductors
UBA20261_UBA20262
Preliminary data sheet
Fig 7.
Temp > T
Boost and burn state machine
Boost_Disable
j(bp)(bst)
7.1.7 Hold state
burn select
OR
burn
00
10
The hold state is a special state that reduces lamp flicker at deep dim levels, on or near
dim and ignition threshold levels. The IC enters the hold state after an ignition failure or
when the low supply voltage V
(see
A repeated drop in supply voltage below V
increment the ignition attempt counter. The hold state is entered, delaying a new preheat
cycle with the same time delay/mechanism by the hold state retention time as shown in
Figure
When CP is below V
start-up state as shown in
voltage drops below V
With a 470 nF capacitor on the CP pin, the typical hold state retention delay is between
1 s and 1.7 s. This delay is dependent on where the preheat cycle was cut-off on the rising
or falling edge of the preheat timing. The retention time for a failed ignition always starts
from the top of the rising edge on the CP pin (see
In the hold state, a hold state latch is set (hold state latch = 1) and the oscillator is
stopped. In addition, the HS transistor is non-conductive and the LS transistor is
conducting.
The voltage on the V
the CP pin reaches V
the current drawn by the IC supply pin V
V
Figure
i(CSI)
(66 % level)
5.
= V
boost_transition timer ended
Temp < T
otp(CSI)
3).
Temp < T
NOT Boost_Disable
OR temp > T
All information provided in this document is subject to legal disclaimers.
Temp > T
j(otp)
j(bp)bst
th(rel)CP
DD
th(rel)CP
Rev. 1 — 9 September 2011
- T
DD(rst)
j(otp)
j(otp)(hys)
j(otp)
pin alternates between V
V
AND
i(CSI)
Figure
(100 % level)
BOOST AND BURN
, the IC is released from the hold state and moves to the
and the IC is reset.
(see
= V
DD
STATES
damp(CSI)
3. Alternatively, the hold state ends when the supply
drops below V
Figure
boost timer running
600 V and 350 V power IC for step dimmable CFLs
boost transition
boost
DD
01
11
5). The alternating supply voltage is caused by
Temp > T
OR boost timer ended
DD(stop)
. The supply current is less than 220 A, when
DD(stop)
DD(start)
j(end)bst
in preheat or ignition states, does not
Figure
Boost_ratio = 1
in the ignition or preheat states
and V
NOT (Boost OR Boost transition)
5).
Dim_1 state AND Boost
DD(stop)
UBA20261/2
Boost_ratio = 1.5
until the voltage on
© NXP B.V. 2011. All rights reserved.
001aam767
10 of 32