uba2015t/n1 NXP Semiconductors, uba2015t/n1 Datasheet - Page 14

• Manufacturer Part Number: uba2015t/n1
• Description: 600 V Fluorescent Lamp Driver With Pfc, Linear Dimming And Boost Function
• Manufacturer: NXP Semiconductors

NXP Semiconductors
UBA2016A_15_15A
Objective data sheet
7.4.5 Ignition
7.4.6 Auto-restart
7.4.7 Burn
The preheat frequency for UBA2015 and UBA2015A can also be regulated via pin PH/EN.
UBA2015 and UBA2015A support current controlled preheat and fixed frequency preheat.
During preheat the output voltage of pin PH/EN is V
external resistor R
current of the VCO (the current at pin CF with no fault condition present and the capacitor
at that pin being charged minus the same current at f
of the VCO is bigger the frequency is being decreased (by charging pin CIFB with
I
increased (by discharging pin CIFB with I
Current and fixed frequency control mechanisms are active at the same time. For fixed
frequency preheat using pin PH/EN, the half-bridge current sense resistor connected to
pin SLHB should be small enough not the activate the current control mechanism. If
current controlled preheat is used, pin PH/EN should be left open (except of course for the
open collector or open drain that drives the enable function). The preheat time t
be set with capacitor C
After the Preheat state the IC enters the Ignition state. During the Ignition state the
switching frequency is decreased by charging pin CIFB with I
increasing lamp voltage until the lamp ignites (see point C in
application with UBA2015A”
and lamp-on or f
average absolute voltage on pin IFB is above lamp-on detection threshold V
the voltage on pin VFB is more then 50 % of each clock cycle below the lamp-on detection
threshold V
If either saturation, overvoltage or hard switching regulation (UBA2016A only) is triggered
it will overrule the frequency sweep down and hold the frequency at the border where the
fault appeared and start the fault timer. When the fault timeout t
enters Auto-restart state if it was the first ignition attempt, otherwise it will go to the Stop
state; see
The Auto-restart state is entered after a fault time out in the Ignition state during the first
ignition attempt. See
draws supply current I
VDD until the voltage on this pin drops below V
state. Here the VDD capacitor will be charged again to start a second ignition attempt. The
bleeder current must be between standby current I
can be set between the two ignition attempts with the capacitor at pin VDD to reduce
stress on the HB components.
In Burn state the lamp current regulation and all protection circuits are active. The boost
function (available in UBA2016A only) is also enabled.
ch(CIFB)
). If the current through the external resistor is bigger the frequency will be
Figure 9 “State
th(lod)(VFB)
All information provided in this document is subject to legal disclaimers.
sw(low)
ext(PH/EN)
Figure 9 “State
and after a delay t
restart(VDD)
(lowest frequency) is detected. Lamp-on detection occurs when the
CPT
Rev. 1 — 20 May 2011
diagram”.
on pin CPT.
connected to this pin sinks is compared to
or
Figure 11 “Resonance curve application with
. This will slowly discharge the buffer capacitor on pin
diagram”. When the IC is in Auto-restart state, it
d(lod)
dch(CIFB)
.
restart(VDD)
).
UBA2016A/15/15A
stb(VDD)
ph(PH/EN)
sw(low)
. The IC then enters the Standby
600 V fluorescent lamp driver
). As long as the output current
and I
. The output current that an
Figure 10 “Resonance curve
ch(CIFB)
to(fault)
restart(VDD)
. This will result in
is reached the IC
4
© NXP B.V. 2011. All rights reserved.
⁄
5
. A time delay
of the output
th(lod)(IFB)
UBA2016A”)
to(ph)
14 of 42
can
and