UBA2015 PHILIPS [NXP Semiconductors], UBA2015 Datasheet - Page 12

• Manufacturer Part Number: UBA2015
• Description: 600 V fluorescent lamp driver with PFC, linear dimming and boost function
• Manufacturer: PHILIPS [NXP Semiconductors]

NXP Semiconductors
UBA2016A_15_15A
Product data sheet
7.4.1 Reset
7.4.2 Standby
7.4.3 Oscillating states (Preheat, Ignition and Burn)
7.4.4 Preheat
When voltage on pin VDD is below the reset voltage V
driver are LOW. All internal latches are reset. When voltage on pin VDD rises above
V
In STANDBY state the low-side gate driver is on (GLHB is HIGH).The floating supply
capacitor C
Preheat state is entered.
The highest and lowest oscillation frequency can be set with capacitor C
the CF pin. The oscillator is implemented in such a way that the lowest frequency f
the most accurate. In any oscillating state (Preheat, Ignition or Burn), when VDD voltage
drops below V
when GLHB is HIGH and enters the STANDBY state.
The oscillating frequency starts at f
with UBA2015A”
remains at that frequency until the PFC output is sufficient (the voltage at pin FBPFC rises
above the PFC voltage OK threshold voltage on pin FBPFC, V
voltages at pins CPT and VFB settle above their pin short protection levels
(V
the Preheat state; see
11 “Resonance curve application with UBA2016A”
I
rise. This will cause the switching frequency to decrease (pin CIFB is the input for the
voltage controlled oscillator). This will cause an increase in half-bridge current (assuming
the switching frequency is higher than the load resonance frequency). This current is
measured via pin SLHB using a resistor connected between the source of the low-side
switch and ground. When the voltage on pin SLHB rises above the preheat current control
voltage V
increased. When the voltage drops below V
causes the frequency to decrease.
ch(CIFB)
rst(VDD)
VFB
>
to the externally connected compensation network on this pin and its voltage will
, the IC will enter STANDBY state.
V
th(osp)(VFB)
crtl(ph)SLHB
FSHB
stop(VDD)
All information provided in this document is subject to legal disclaimers.
is then charged. When the VDD voltage rises above V
or
, discharge current I
Figure 11 “Resonance curve application with UBA2016A”
and V
Rev. 3 — 16 November 2011
Figure 10 “Resonance curve application with UBA2015A”
or overtemperature is detected, the half-bridge stops oscillation
CPT
>
V
th(scp)(CPT)
sw(high)
dch(CIFB)
(see
). The half-bridge current is regulated when in
th(ocp)SLHB
Figure 10 “Resonance curve application
to pin CIFB and the frequency is
UBA2016A/15/15A
point B. Pin CIFB supplies a current
rst(VDD)
, current I
600 V fluorescent lamp driver
, both gates of the half-bridge
th(VPFCok)FBPFC
ch(CIFB)
from pin CIFB
startup(VDD)
© NXP B.V. 2011. All rights reserved.
CF
connected to
) and the
point A) and
or
, the
sw(low)
Figure
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is