MIC4830YMM Micrel Inc, MIC4830YMM Datasheet - Page 8

• Manufacturer Part Number: MIC4830YMM
• Description: IC DRIVER LN 180VP-P EL 8-MSOP
• Manufacturer: Micrel Inc
• Type: EL Lamp Driverr

Specifications of MIC4830YMM

• Operating Temperature: -40°C ~ 85°C
• Frequency: 60 ~ 1000 Hz
• Current - Supply: 45µA
• Voltage - Supply: 1.8 V ~ 5.5 V
• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• Module Configuration: Half Bridge
• Supply Current: 45µA
• Meter Display Type: Electroluminescent Lamp
• Supply Voltage Range: 1.8V To 5.5V
• Driver Case Style: MSOP
• No. Of Pins: 8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Current - Output: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: 576-2126-5; 576-2126-5; 576-2976-5

Application Information
Inductor
A 220µH Murata (LQH4C221K04) inductor is
recommended for most applications.
inductors with smaller values can handle more
current. Lowering the inductance allows the boost
regulator to draw more input current to deliver more
energy every cycle.
inductor may be used to drive larger panels or make
the current panel brighter.
required as using a low value inductor with a low
switching
exceeding the absolute maximum rating of the
switch node and/or the CS pin. If the application
uses a low input voltage (1.8 to 3V), a lower value
inductor, such as 100µH, may be used in order to
drive the EL lamp at max brightness without issue.
Diode
The diode must have a high reverse voltage (150V),
since the output voltage at the CS pin can reach up
to 110V. A fast switching diode with lower forward
voltage and higher reverse voltage (150V), such as
BAV20WS/BAS20W, can be used to enhance
efficiency.
Output Capacitor
Low ESR capacitors should be used at the regulated
boost output (CS pin) of the MIC4830 to minimize
the switching output ripple voltage. The larger the
output capacitance, the lower the output ripple at the
CS pin. The reduced output ripple at the CS pin
along with a low ESR capacitor improves the
efficiency of the MIC4830 circuit. Selection of the
Micrel
July 2009
frequency
As a result, a lower value
may
However, caution is
result
in
Generally,
voltages
capacitor value will depend upon the peak inductor
current, inductor size, and the load. The MIC4830 is
designed for use with an output capacitance as low
as 2.2nF. For minimum audible noise, the use of a
C0G/NPO
recommended. TDK and AVX offer C0G/NPO
dielectric capacitors in capacitances up to 2.7nF at
200V to 250V rating in 0805 size. If output ripple is a
concern a 0.01µF/200V X7R output capacitor is
recommended.
EL Lamp Terminals (VA, VB)
An EL lamp is connected from VA to VB as the load.
The high voltage alternated across VA and VB by
the H-Bridge cycles generate luminance. The
voltage at VA and VB should not exceed the voltage
at V
present when noisy enable signals such as those
often generated by mechanical switches are applied
to the driver’s inputs. To prevent over voltage at VA
and VB, 10kΩ resistors may be placed in series from
VA to the EL panel and from VB to the EL panel. An
alternative to the use of 10kΩ resistors is to apply a
diode from the CS pin to VA and VB, where the
cathode of the diode is on the CS side and the
anode is on the VA and VB side, respectively.
8
CS
by more than 3V. This situation may become
dielectric
output
capacitor
M9999-070709-C
MIC4830
is