Philips Semiconductors
Product specification
630 V driver IC for CFL and TL lamps
FEATURES
•
Adjustable preheat and ignition time
•
Adjustable preheat current
•
Adjustable lamp power
•
Lamp temperature stress protection at higher mains
voltages
•
Capacitive mode protection
•
Protection against a too-low drive voltage for the power
MOSFETs.
QUICK REFERENCE DATA
SYMBOL
High voltage supply
V
FS
Start-up state
V
VS(start)
V
VS(stop)
I
VS(standby)
Preheat mode
f
start
t
ph
V
RS(ctrl)
f
B
t
ign
f
B
t
no
I
tot
start frequency
preheat time
control voltage at pin RS
C
CP
= 100 nF
−
−
−
−
−
−
−
f
B
= 43 kHz
−
−
−
I
RHV
= 0.75 mA
I
RHV
= 1.0 mA
I
i(RHV)
operating range of input current at pin RHV
−
−
0
108
666
−600
42.9
625
oscillator start voltage
oscillator stop voltage
standby current
V
VS
= 11 V
−
−
−
11.95
10.15
200
high side supply voltage
I
FS
< 15
µA;
t < 0.5 s
−
−
PARAMETER
CONDITIONS
MIN.
TYP.
GENERAL DESCRIPTION
UBA2021
The UBA2021 is a high-voltage IC intended to drive and
control Compact Fluorescent Lamps (CFL) or fluorescent
TL-lamps. It contains a driver circuit for an external
half-bridge, an oscillator and a control circuit for starting
up, preheating, ignition, lamp burning and protection.
MAX.
UNIT
630
−
−
−
−
−
−
−
−
−
−
−
−
−
−
−
1000
V
V
V
µA
kHz
ms
mV
Frequency sweep to ignition
bottom frequency
ignition time
kHz
ms
Normal operation
bottom frequency
non-overlap time
total supply current
42.9
1.4
1
126
75
kHz
µs
mA
Ω
Ω
kHz
kHz
µA
R
G1(on)
, R
G2(on)
high and low side on resistance
R
G1(off)
, R
G2(off)
high and low side off resistance
Feed-forward
f
ff
feed-forward frequency
63.6
84.5
−
2001 Jan 30
2
Philips Semiconductors
Product specification
630 V driver IC for CFL and TL lamps
PINNING
UBA2021
SYMBOL
FS
G1
S1
n.c.
VS
G2
PGND
CP
RS
RREF
SGND
CF
RHV
CI
PIN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
gate high transistor (T1)
source high transistor (T1)
DESCRIPTION
high side floating supply voltage
high-voltage spacer, not to be connected
low voltage supply
gate low transistor (T2)
power ground
timing/averaging capacitor
current monitoring input
reference resistor
signal ground
oscillator capacitor
start-up resistor/feed-forward resistor
integrating capacitor
handbook, halfpage
handbook, halfpage
FS
G1
S1
n.c.
VS
G2
PGND
1
2
3
4
5
6
7
MGS989
14 CI
13 RHV
12 CF
FS
G1
S1
n.c.
VS
G2
PGND
1
2
3
4
5
6
7
MGS990
14 CI
13 RHV
12 CF
UBA2021T
11 SGND
10 RREF
9
RS
UBA2021P
11 SGND
10 RREF
9
RS
8 CP
8 CP
Fig.2 Pin configuration (SO14).
Fig.3 Pin configuration (DIP14).
2001 Jan 30
4
Philips Semiconductors
Product specification
630 V driver IC for CFL and TL lamps
FUNCTIONAL DESCRIPTION
Introduction
handbook, halfpage
UBA2021
MGS991
The UBA2021 is an integrated circuit for electronically
ballasted compact fluorescent lamps and their derivatives
operating with mains voltages up to 240 V (RMS). It
provides all the necessary functions for preheat, ignition
and on-state operation of the lamp. In addition to the
control function, the IC provides level shift and drive
functions for the two discrete power MOSFETs, T1 and T2
(see Fig.7).
Initial start-up
Initial start-up is achieved by charging capacitor CS9 with
the current applied to pin RHV. At start-up, MOSFET T2
conducts and T1 is non-conducting, ensuring C
boot
becomes charged. This start-up state is reached for a
supply voltage V
VS(reset)
(this is the voltage level at pin VS
at which the circuit will be reset to the initial state) and
maintained until the low voltage supply (V
VS
) reaches a
value of V
VS(start)
. The circuit is reset in the start-up state.
Oscillation
When the low voltage supply (V
VS
) has reached the value
of V
VS(start)
the circuit starts oscillating in the preheat state.
The internal oscillator is a current-controlled circuit which
generates a sawtooth waveform. The frequency of the
sawtooth is determined by the capacitor C
CF
and the
current out of pin CF (mainly set by R
RREF
). The sawtooth
frequency is twice the frequency of the signal across the
load. The IC brings MOSFETs T1 and T2 alternately into
conduction with a duty factor of approximately 50%.
Figure 4 represents the timing of the IC. The circuit block
'non-overlap' generates a non-overlap time t
no
that
ensures conduction periods of exclusively T1 or T2. Time
t
no
is dependent on the reference current I
RREF
.
start-up
VCF
0
internal
clock
0
V(G1-S1)
0
V(G2)
0
time
t no
t no
Fig.4 Oscillator timing.
Operation in the preheat mode
The circuit starts oscillating at approximately 2.5
×
f
B
(108 kHz). The frequency gradually decreases until a
defined value of current I
shunt
is reached (see Fig.5). The
slope of the decrease in frequency is determined by
capacitor C
CI
. The frequency during preheating is
approximately 90 kHz. This frequency is well above the
resonant frequency of the load, which means that the lamp
is off; the load consists of L2, C5 and the electrode
resistance only. The preheat time is determined by
capacitor C
CP
. The circuit can be locked in the preheat
state by connecting pin CP to ground. During preheating,
the circuit monitors the load current by measuring the
voltage drop over external resistor R
shunt
at the end of
conduction of T2 with decision level V
RS(ctrl)
. The
frequency is decreased as long as V
RS
> V
RS(ctrl)
. The
frequency is increased for V
RS
< V
RS(ctrl)
.
2001 Jan 30
5
京公网安备 11010802033920号
Copyright © 2005-2026 EEWORLD.com.cn, Inc. All rights reserved
电子工程世界
