IR2166SPBF International Rectifier, IR2166SPBF Datasheet - Page 19

• Manufacturer Part Number: IR2166SPBF
• Description: IC PFC/BALLAST CONTROL 16-SOIC
• Manufacturer: International Rectifier
• Type: PFC/Ballast Controllerr

Specifications of IR2166SPBF

• Frequency: 39 ~ 50 kHz
• Current - Supply: 10mA
• Current - Output: 400mA
• Voltage - Supply: 11.5 V ~ 15.6 V
• Operating Temperature: -25°C ~ 125°C
• Package / Case: 16-SOIC (3.9mm Width)
• Package: 16-lead SOIC Narrow
• Circuit: Fluorescent Ballast IC
• Offset Voltage (v): 600
• Output Source Current Min (ma): 250
• Output Sink Current Min (ma): 400
• Vcc Range (v): 10-25V with UVLO
• Output Voltage Min (v): 10
• Output Voltage Max (v): 25
• Pbf: PbF Option Available
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

I. Ballast Section
Functional Description
Under-voltage Lock-Out Mode (UVLO)
The under-voltage lock-out mode (UVLO) is
defined as the state the IC is in when VCC is
below the turn-on threshold of the IC. To identify
the different modes of the IC, refer to the State
Diagram shown on page 7 of this document. The
IR2166 undervoltage lock-out is designed to
maintain an ultra low supply current of less than
400uA, and to guarantee the IC is fully functional
before the high and low side output drivers are
activated. Figure 1 shows an efficient supply
voltage using the start-up current of the IR2166
together with a charge pump from the ballast
output stage (R
The start-up capacitor (CVCC) is charged by
current through supply resistor (RSUPPLY)
minus the start-up current drawn by the IC. This
resistor is chosen to set the line input voltage
turn-on threshold for the ballast . Once the
capacitor voltage on VCC reaches the start-up
threshold, and the SD pin is below 5.0 volts, the
IC turns on and HO and LO begin to oscillate.
The capacitor begins to discharge due to the
increase in IC operating current (Figure 2).
www.irf.com
V
V
BUS
BUS
(+)
(-)
Figure 1, Start-up and supply circuitry.
SUPPLY
IR2166
, C
16
15
14
13
12
11
R
VCC
SUPPLY
HO
VS
VCC
VB
COM
LO
, D
CP1
D
C
C
BOOT
R
BOOT
VCC
CS
M1
and D
M2
D
Half-Bridge
CP1
Output
CP2
C
D
SNUB
CP2
).
During the discharge cycle, the rectified current
from the charge pump charges the capacitor above
the IC turnoff threshold. The charge pump and
the internal 15.6V zener clamp of the IC take over
as the supply voltage. The start-up capacitor and
snubber capacitor must be selected such that
enough supply current is available over all ballast
operating conditions. A bootstrap diode (DBOOT)
and supply capacitor (CBOOT) comprise the
supply voltage for the high side driver circuitry.
To guarantee that the high-side supply is charged
up before the first pulse on pin HO, the first pulse
from the output drivers comes from the LO pin.
During under-voltage lockout mode, the high-
and low-side driver outputs HO and LO are both
low, pin CT is connected internally to COM to
disable the oscillator, and pin CPH is connected
internally to COM for resetting the preheat time.
Preheat Mode (PH)
The preheat mode is defined as the state the IC
is in when the lamp filaments are being heated to
their correct emission temperature. This is
necessary for maximizing lamp life and reducing
the required ignition voltage. The IR2166 enters
preheat mode when VCC exceeds the UVLO
positive-going threshold. HO and LO begin to
V
C1
Figure 2, Supply capacitor (C
R
TIME
CONSTANT
V
V
SUPPLY
UVLO+
UVLO-
VHYST
& C
VCC
DISCHARGE
IR2166 & (PbF)
C
VCC
CHARGE PUMP
OUTPUT
DISCHARGE
TIME
VCC
INTERNAL VCC
ZENER CLAMP VOLTAGE
) voltage.
t
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