MAX4990E Datasheet, PDF (11/15 Pages) Maxim Integrated Products – High-Voltage, ±15kV ESD-Protected Electroluminescent Lamp Driver

High-Voltage, ±15kV ESD-Protected
Electroluminescent Lamp Driver
R_C
1MΩ
R_D
1500Ω
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
HIGH-
VOLTAGE
DC
SOURCE
Cs
100pF
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
R_C
50MΩ TO 100MΩ
R_D
330Ω
CHARGE-CURRENT-
LIMIT RESISTOR
DISCHARGE
RESISTANCE
HIGH-
VOLTAGE
DC
SOURCE
Cs
150pF
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
Figure 1a. Human Body ESD Test Model
Figure 1c. IEC 61000-4-2 ESD Test Model
I_P 100%
90%
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
AMPS
36.8%
10%
0
0 _tRL
TIME
t_DL
CURRENT WAVEFORM
Figure 1b. Human Body Current Waveform
I
100%
90%
10%
tr = 0.7ns TO 1ns
30ns
t
60ns
Figure 1d. IEC 61000-4-2 ESD Generator Current Waveform
Table 1. Inductor Vendors
INDUCTOR VALUE (µH)
220
330
470
220
330
470
VENDOR
TOKO
Coilcraft
Coilcraft
Coilcraft
Coilcraft
Coilcraft
WEBSITE
www.tokoam.com
www.coilcraft.com
www.coilcraft.com
www.coilcraft.com
www.coilcraft.com
www.coilcraft.com
PART
D312C 1001BS-221M
DO1608C-334ML
DO1608C-474ML
LPS4018-224ML
LPS4018-334ML
LPS4018-474ML
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:
V_P-P
=
200
×
R_DIM
R_SLEW
R_DIM Resistor and C_DIM
Capacitor Selection
The MAX4990E 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
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