參數(shù)資料
型號(hào): UCC3976TRPW
廠商: Texas Instruments, Inc.
元件分類: 基準(zhǔn)電壓源/電流源
英文描述: Low consumption voltage and current controller for battery chargers and adaptors
中文描述: 鎮(zhèn)流器/背光控制器/驅(qū)動(dòng)器| TSSOP封裝| 8引腳|塑料
文件頁數(shù): 11/28頁
文件大?。?/td> 433K
代理商: UCC3976TRPW
SLUS499A
NOVEMBER 2001
REVISED JANUARY 2002
11
www.ti.com
APPLICATION INFORMATION
L
C
R
1 : n
VIN
CINPUT
COUT
VOUT
RLOAD
UDG
01100
Figure 8. Equivalent Piezoelectric Transformer Circuit Model
The component values depend on the PZT
s construction. A large primary capacitance (C
INPUT
) is formed as
a result of the multi-layer construction of the primary electrodes and material dielectric constant. The output
capacitance is much smaller due to the distance between the primary and secondary electrodes. Typical values
of C
INPUT
and C
OUT
for a multi
layer PZT may be 0.2
μ
F and 20 pF respectively, where a single layer design
would have lower C
INPUT
since layers =1.
length
width
layers
2
thickness
C
INPUT
C
OUTPUT
2
thickness
width
length
C
INPUT
and an external transformer or inductor(s) are used to form a primary-side L-C resonant circuit as
depicted in Figures 1, 2 and 3. These circuits provide sinusoidal waveforms at the primary, allowing the PZT
to operate at higher efficiency. The mechanical resonant frequency (
ω
0
) of the PZT (which differs from the
natural primary L-C resonant frequency) is proportional to the material elasticity (Y), density (
ρ
) and length.
0
1
length
Y
The mechanical piezoelectric gain near a single resonant frequency can modeled by a series R, L, and C circuit
as depicted in Figure 8.
0
1
L
C
Q
0
L
R
Figure 9 illustrates the gain-vs-output load and frequency characteristics for a 12-layer, 70-kHz PZT with the
following Figure 8 values:
C
INPUT
= 0.2
μ
F
C
OUT
= 30 pF
n = 30
series RLC (2
, 1
μ
H, 6 nF)
As shown in Figure 9, the ceramic transformer provides high Q and gain under light or no-load conditions
producing a high-strike potential. Once the lamp strikes the transformer becomes loaded, causing the
transformer gain to decrease and resonant frequency to shift. The piezoelectric transformer is typically operated
on the right side of resonance to allow the lamp to be struck and operated with a single direction control circuit.
A typical application has separate start (A), strike (B), and operating (C) frequencies (see Figure 9).
(3)
(4)
(5)
(6)
(7)
相關(guān)PDF資料
PDF描述
UCC3977TRPW BALLAST/BACKLIGHT CONTROLLER/DRIVER|TSSOP|8PIN|PLASTIC
UCC35705DGKTR HIGH - SPEED VOLTAGE MODE PULSE MODE WIDTH MODULATOR
UCC35706DTR HIGH - SPEED VOLTAGE MODE PULSE MODE WIDTH MODULATOR
UCC35706DGKTR Aluminum Electrolytic Radial Lead High Ripple Capacitor; Capacitance: 330uF; Voltage: 400V; Case Size: 25x50 mm; Packaging: Bulk
UCC35705EVM UCC35705 Evaluation Module(UCC35705評(píng)估模塊)
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
UCC3977PW 功能描述:LCD 驅(qū)動(dòng)器 Multi-Topology Piezoelectric RoHS:否 制造商:Maxim Integrated 數(shù)位數(shù)量:4.5 片段數(shù)量:30 最大時(shí)鐘頻率:19 KHz 工作電源電壓:3 V to 3.6 V 最大工作溫度:+ 85 C 最小工作溫度:- 20 C 封裝 / 箱體:PDIP-40 封裝:Tube
UCC3977PWG4 功能描述:LCD 驅(qū)動(dòng)器 Multi-Topology Piezoelectric RoHS:否 制造商:Maxim Integrated 數(shù)位數(shù)量:4.5 片段數(shù)量:30 最大時(shí)鐘頻率:19 KHz 工作電源電壓:3 V to 3.6 V 最大工作溫度:+ 85 C 最小工作溫度:- 20 C 封裝 / 箱體:PDIP-40 封裝:Tube
UCC3977PWR 制造商:Texas Instruments 功能描述:
UCC40V680UF 制造商:United Chemi-Con 功能描述:AL040X768 85C 13X31
UCC500-30GM-IU-V1 B540 制造商:PEPPERL+FUCHS 功能描述:Sensor, Ultrasonic, Chem Resistant, 094792