參數(shù)資料
型號(hào): MC33441DTBR2
廠商: ON SEMICONDUCTOR
元件分類(lèi): 顯示驅(qū)動(dòng)器
英文描述: Electroluminescent Lamp Driver IC
中文描述: EL DISPLAY DRIVER, PDSO8
封裝: 3.10 X 4.50 MM, 1.05 MM HEIGHT, 0.65 MM PITCH, TSSOP-8
文件頁(yè)數(shù): 5/12頁(yè)
文件大?。?/td> 152K
代理商: MC33441DTBR2
MC33441
http://onsemi.com
5
will be turned off and the energy will release to the EL lamp.
And, those switches will remain off until the next clock cycle.
H–Bridge Network
To achieve the 140V peak–to–peak voltage, H–bridge
network is used to charge and discharge the EL lamp. The
switching frequency of the bridge network is controlled by a
clock signal from the divider with its frequency much lower than
the one to the coil–driver. Moreover, to reduce the current
consumption, the biasing current to the two low–side switches
of the H–bridge is not activated until the coil–driver circuit
needed to release the energy to the EL lamp. Then, the biasing
circuit will be on and be ready before the main switch in the
coil–driver really starts to turn off.
External Components
System designer will base on the application to decide the size
and the type of the EL lamp to be used. The external resistance
(REXT) at RT1 pin determines the excitation frequency (FEL) for
the lamp. The relationship between REXT and the frequency is:
FEL = FOSC
384
By substitute the equation of FOSC from
Oscillator &
Frequency Divider
.
FEL
4.341
10
7
REXT
Hz
so
REXT
4.341
10
7
FEL
Moreover, if a low TC resistor is used, the oscillator
frequency’s TC can be kept low. The filter capacitor is to provide
a smooth and more stable output waveform for the EL lamp.
The value of this capacitor depends on the input voltage and the
coil’s inductance value. Equations below can be used to estimate
filter capacitor’s value at different input voltage.
Best Case Approximation for the Filter Capacitor:
CFILTER
0.026
(Vin
VSW)
2
(L
FOSC
2
)
Worst Case Approximation for the Filter Capacitor:
CFILTER
0.085
(Vin
VSW)
2
(L
FOSC
2
)
where VIN is the input voltage, VSW is voltage across the
switch when it is on, L is the coil’s value and FOSC is the
clock frequency.
Measurement below is recorded with the condition: coil
= 1mH, EL lamp = 2.2nF and at room temperature.
Table 1: Reference for CFILTER
VDD
REXT
1.8V
100K–130K
CFILTER
5n–10nF
áááááááááááááá
áááááááááááááá
áááááááááááááá
áááááááááááááá
áááááááááááááá
2.0V
100K–130K
10n–22nF
2.5V
100K–130K
10n–22nF
3.0V
100K–130K
22nF–33nF
相關(guān)PDF資料
PDF描述
MC33461SQ-09CTR Under Voltage Detector Series
MC33461SQ-20CTR Under Voltage Detector Series
MC33461SQ-27CTR Under Voltage Detector Series
MC33461SQ-30CTR Under Voltage Detector Series
MC33461SQ-32CTR SCREW MACHINE PHIL 6-32X1/4 SS
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MC33460SQ09ATR 制造商:ONS 功能描述:ON SEMICONDUCTOR S10M2D
MC33460SQ-09ATR 制造商:Rochester Electronics LLC 功能描述:- Tape and Reel
MC33460SQ20ATR 制造商:ONS 功能描述:ON SEMICONDUCTOR NXC4D, S7E7B
MC33460SQ-20ATR 制造商:ONS 功能描述:ON SEMICONDUCTOR NXC4D, S7E7B
MC33460SQ27ATR 制造商:ONS 功能描述:ON SEMICONDUCTOR NXC7A