uba20271 NXP Semiconductors, uba20271 Datasheet - Page 5

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

NXP Semiconductors
7. Functional description
UBA20271_UBA20272
Product data sheet
The UBA20271/2 are ICs with integrated half-bridge MOSFETs in self ballasted
high-power CFL and their derivatives. The UBA20271/2 are equipped with variable
dimming functionality that has a logarithmic corrected natural dimming function. This
function enables a less sensitive brightness control of the lamp at low dim levels.
The UBA20271/2 are rated up to a maximum continuous rectified mains voltage of 500 V
(peak 600 V) and lamp power-up to 20 W. The UBA20271/2 include all the necessary
functions for preheat, ignition, boost, and on-state operation of the lamp and includes a
linear dimming feature. In addition, several protection measures are included that
safeguard the functioning of the CFL and controller. The controller states are shown in
Figure
Fig 3.
(1) V
(2) V
(3) (End of ignition time AND HOLD = 0) OR V
(4) End of ignition AND HOLD = 1
(5) V
(6) V
3.
State diagram
DD
DD
CP
DD
(6)
> V
< V
< V
< V
All information provided in this document is subject to legal disclaimers.
th(pd)CP
DD(start)
DD(stop)
DD(stop)
350 V and 600 V Power ICs for dimmable compact fluorescent lamps
V
DD
> V
preheat time
Rev. 2 — 8 September 2011
OR V
OR overcurrent fault time >
OR V
AND V
DD(rst)
completed
BOOST AND BURN
START-UP STATE
PREHEAT STATE
IGNITION STATE
RESET STATE
i(DCI)
i(DCI)
HOLD = 0
i(DCI)
STATES
V
DD
< V
< V
= 0
(1)
> V
Ignition_Detected
th(start)DCI
th(start)DCI
th(start)DCI
V
DD
< V
DD(rst)
 V
 V
AND (HOLD = 0 OR V
th(hys)DCI
th(hys)DCI
DD
1
⁄
10
< V
t
ph
V
V
DD
CP
DD(stop)
OR f
< V
(2)
(3)
< V
bridge(max)
th(rel)CP
DD(rst)
OR V
i(DCI)
CP
HOLD STATE
detected in capacitive mode
(4)
(5)
< V
HOLD = 1
UBA20271/2
< V
th(rel)CP
th(start)DCI
POWER-DOWN STATE
)
© NXP B.V. 2011. All rights reserved.
 V
th(hys)DCI
001aam665
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