uba20270 NXP Semiconductors, uba20270 Datasheet - Page 5

• Manufacturer Part Number: uba20270
• Description: 600 V Driver Ic For Dimmable Compact Fluorescent Lamps
• Manufacturer: NXP Semiconductors

NXP Semiconductors
7. Functional description
UBA20270
Product data sheet
The UBA20270 is an IC for driving external half-bridge MOSFETs in self ballasted
high-power CFL and their derivatives. The UBA20270 is equipped with a dimming control
input that has a logarithmic corrected natural dimming function. This function enables a
less sensitive brightness control of the lamp at low dim levels.
The UBA20270 is rated up to a maximum continuous rectified mains voltage of 500 V
(peak 600 V). The UBA20270 includes all the necessary functions for preheat, ignition,
boost, and on-state operation of the lamp. In addition, the UBA20270 includes several
protection measures that safeguard the functioning of the CFL and controller. The
controller states are shown in
Fig 3.
(1) V
(2) V
(3) (End of ignition time AND HOLD = 0) OR V
(4) End of ignition time AND HOLD = 1
(5) V
(6) V
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)
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
600 V Driver IC for dimmable compact fluorescent lamps
DD
Figure
< V
< V
= 0
(1)
> V
Ignition_Detected
th(start)DCI
th(start)DCI
th(start)DCI
V
DD
3.
< 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
< V
th(rel)CP
th(start)DCI
UBA20270
POWER-DOWN STATE
)
© NXP B.V. 2011. All rights reserved.
 V
th(hys)DCI
001aam665
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