MAX14521E_15 Datasheet, PDF (1/21 Pages) Maxim Integrated Products – Quad, High-Voltage EL Lamp Driver with I2C Interface

MAX14521E
EVALUATION KIT AVAILABLE
Quad, High-Voltage EL Lamp Driver
with I²C Interface
General Description
The MAX14521E is a quad-output high-voltage DC-AC
converter that drives four electroluminescent (EL) lamps.
The device features a 2.7V to 5.5V input range that allows
the device to accept a variety of voltage sources such as
single-cell lithium-ion (Li+) batteries. The lamp outputs of
the device generate up to 300V_P-P for maximum lamp
brightness. The high-voltage outputs are ESD protected
up to ±15kV Human Body Model (HBM), ±6kV Contact
Discharge, and ±8kV Air Gap Discharge, as specified in
IEC 61000-4-2.
The MAX14521E uses a high-voltage full-bridge output
stage to convert the high voltage generated by the
boost converter to a sinusoidal output waveform. The
MAX14521E utilizes a high-frequency spread-spectrum
oscillator to reduce the amount of EMI/EFI generated by
the boost-converter circuit.
The MAX14521E provides an I²C interface to set the
boost converter and EL output switching frequencies
through an 8-bit register and the peak output voltages
with 5 bits of resolution. The MAX14521E also provides
an adjustable automatic ramping feature that slowly
increases or decreases the peak output voltage when a
change is made to the output amplitude. The slew rate of
the automatic ramp is set with 3 bits of resolution through
the I²C interface and it is independent for each channel.
The MAX14521E features an audio auxiliary input AUX
that modulates the EL output voltage and frequency for
dynamic lighting effects.
The MAX14521E is available in a small, 4mm x 4mm,
24-pin TQFN package, and specified over the extended
-40°C to +85°C operating temperature range
Applications
●● Keypad Backlighting
●● LCD Backlighting
●● PDAs
●● Smartphones
Ordering Information
PART
TEMP RANGE
PIN-PACKAGE
MAX14521EETG+
-40°C to +85°C
24 TQFN-EP*
+Denotes lead(Pb)-free/RoHS-compliant package.
*EP = Exposed pad.
Benefits and Features
●● Integration Reduces Required Board Space
• Integrated ±15kV ESD Protection
• Low Number of Needed Discrete Components
• 4mm x 4mm, 24-Pin TQFN Package
●● Enhances Lamp Performance
• 300V_P-P Maximum Output for Highest Brightness
• ±3% EL Output Frequency Accuracy for Truest EL
Panel Color
• Individually Adjustable Output Brightness Ramping
Rate and Individual Dimming Control
• Audio Input for Dynamic Lighting Effects
• I²C Interface for Control of Brightness, EL Frequency,
Boost Frequency, Shape
●● Eases System Integration
• Sinusoidal Output for Low Audible Noise
• High-Frequency Spread-Spectrum Oscillator
Reduces EMI/EFI Generation
●● Ideal for Battery-Powered Devices
• 100nA Shutdown Current
• 2.7V to 5.5V Input Voltage Range
Pin Configuration appears on last page.
Typical Operating Circuit
VDD
VBAT
10µF
CSN
330pF
LX
D
RSN
CCS
20Ω
TO BASEBAND/PMIC
0.1µF
9
3 _CS
VDD
EL LAMP1
EL1 ¹
6
5
PGND
EL2
LX
MAX14521E
EL LAMP1
23
EL LAMP1
10 _SDA
EL3 ¹⁹
11 _SCL
7 _A0
8 _A1
EL LAMP1
EL4 ¹⁷
COM ²¹
12
RB
13 AUDIO
GND
AUX
LINE-IN
15
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