LX1686E
TM
®
Digital Dimming CCFL Controller IC
P
RODUCTION
D
ATA
SHEET
FUNCTIONAL PIN DESCRIPTION
P
IN
N
AME
AOUT
VSS_P
VSS
AFD_C
RAMP_C
RAMP_R
FVERT
PD_CR
VCO_C
BRT_POS
BRITE
DIG_DIM
ENABLE
I_R
BRT
VCOMP
VSNS
ICOMP
ISNS
OLSNS
TRI_C
VDD
VDD_P
BOUT
D
ESCRIPTION
Output driver A, typical 10K pull down resistor to VSS_P.
Power ground for output drivers only.
Signal ground.
Connects to an external capacitor, C
AFD
. Forcing to ground or VDD will make the VCO oscillate at approximately
50% of the maximum VCO frequency. Forcing to VDD/2 will make the VCO oscillate at 2x the FVERT frequency.
Connects to external capacitor C
RAMP
for setting Direct Drive PWM operating frequency.
Connects to external resistor R
RAMP
for setting Direct Drive PWM operating frequency.
Vertical frequency reference digital input. Has internal pull down.
Phase Detector Filter. Part of phase lock loop. Connects to external capacitor and resistor network.
Connects to external capacitor C
VCO
Brightness control polarity. Has internal pull up. Leave open or pull up to VDD for dimming brightness
proportional to BRITE voltage, connect to ground for brightness inversely proportional to BRITE voltage.
Analog voltage input for brightness control.
Digital Dimming Enable internal pull up. Leave open or pull up to VDD for operating in digital dimming mode.
Connect to ground for analog dimming mode.
Chip Enable internal pull up. High enables the chip. Low disables.
Current Reference Resistor. External resistor to ground (Ri) determines internal capacitor C
ICOMP
.
Current Error Amplifier non-inverting input
Voltage Error Amplifier output. Connects to external frequency compensation capacitor C
VCOMP
. Controls soft-
start timing.
Voltage Error Amplifier inverting input.
Current Error Amplifier output. Connects to external frequency compensation capacitor C
ICOMP
.
Current Error Amplifier inverting Input.
Open Lamp Sense Input.
Connects to external capacitor C
TRI
for setting strike Frequency ramp slope.
VDD
Dedicated VDD for output buffers only.
Output Driver B typical 10K pull down resistor to VSS_P.
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Microsemi
.C
OM
P
ACKAGE
D
ATA
P
ACKAGE
D
ATA
Copyright
©
2004
Rev. 1.1, 2006-02-27
Microsemi
Integrated Products
11861 Western Avenue, Garden Grove, CA. 92841, 714-898-8121, Fax: 714-893-2570
Page 3
MICROSEMI [ MICROSEMI CORPORATION ]
