Datasheet

The peak-to-peak voltage is adjusted by connecting a
resistor from the SLEW input to GND together with a
resistor from the DIM input to GND. The equation relating
the peak-to-peak voltage to the resistors is the following:
R
DIM
Resistor and C
DIM
Capacitor Selection
The MAX4990 provides a slow turn-on/-off feature by
connecting a resistor in parallel with a capacitor con-
nected from the DIM input to GND. The reference cur-
rent I
B
is used to charge the resistor and capacitor.
When EN is driven to GND, I
B
is removed, and the volt-
age across the capacitor and resistor decay with a time
constant of RC that provides a slow turn off of the EL
V
R
R
P-P
DIM
SLEW
=×200
MAX4990
High-Voltage, ±15kV ESD-Protected
Electroluminescent Lamp Driver
______________________________________________________________________________________ 11
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
C
s
100pF
R
C
1M
Ω
R
D
1500
Ω
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
Figure 1a. Human Body ESD Test Model
I
P
100%
90%
36.8%
t
RL
TIME
t
DL
CURRENT WAVEFORM
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
I
r
10%
0
0
AMPS
Figure 1b. Human Body Current Waveform
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
C
s
150pF
R
C
50M
Ω
TO 100M
Ω
R
D
330
Ω
HIGH-
VOLTAGE
DC
SOURCE
DEVICE
UNDER
TEST
Figure 1c. IEC 61000-4-2 ESD Test Model
t
r
= 0.7ns TO 1ns
30ns
60ns
t
100%
90%
10%
I
PEAK
I
Figure 1d. IEC 61000-4-2 ESD Generator Current Waveform
Table 1. Inductor Vendors
INDUCTOR VALUE (µH) VENDOR WEBSITE PART
220 TOKO www.tokoam.com D312C 1001BS-221M
330 Coilcraft www.coilcraft.com DO1608C-334ML
470 Coilcraft www.coilcraft.com DO1608C-474ML
220 Coilcraft www.coilcraft.com LPS4018-224ML
330 Coilcraft www.coilcraft.com LPS4018-334ML
470 Coilcraft www.coilcraft.com LPS4018-474ML
220 Cooper Bussmann www.cooperet.com SDH3812-221-R
220 Cooper Bussmann www.cooperet.com SD3110-221-R