28LW-92H (serv.man2) - Sharp TV Service Manual (repair manual). Page 21

The TCET110/ TCET2100/ TCET4100 consists of a phototransistor optically coupled to a gallium 
arsenide infrared-emitting diode in a 4-lead up to 16-lead plastic dual inline package. The elements are 
mounted on one lead frame using a coplanar technique, providing a fixed distance between input and 
output for highest safety requirements.

 

Circuits for safe protective separation against electrical shock according to safety class II (reinforced 
isolation): 
For appl. class I – IV at mains voltage 

”300 V 

For appl. class I – III at mains voltage 

”600 V 

According to VDE 0884, table 2, suitable for: Switch-mode power supplies, line receiver, computer 
peripheral interface, and microprocessor system interface. 

VDE 0884 related features: 
Rated impulse voltage (transient overvoltage) V 

IOTM 

= 8 kV peak 

Isolation test voltage (partial discharge test voltage) V 

pd 

= 1.6 kV 

Rated isolation voltage (RMS includes DC) V 

IOWM 

= 600 V 

RMS 

(848 V peak) 

Rated recurring peak voltage (repetitive) V 

IORM 

= 600 V 

RMS

 

 
General features: 
CTR offered in 9 groups 
Isolation materials according to UL94-VO 
Pollution degree 2 (DIN/VDE 0110 / resp. IEC 664) 
Climatic classification 55/100/21 (IEC 68 part 1) 
Special construction: Therefore, extra low coupling capacity of typical 0.2pF, high Common  Mode 
Rejection 
Low temperature coefficient of CTR  
G = Leadform 10.16 mm; provides creepage distance > 8 mm, for TCET2100/ TCET4100 optional; 
suffix letter ‘G’ is not marked on the optocoupler  
Coupling System U 
 

The TDA9885 is an alignment-free single standard (without positive modulation) vision and sound IF signal 
PLL.  

5 V supply voltage 
Gain controlled wide-band Vision Intermediate Frequency (VIF) amplifier (AC-coupled) 
Multistandard true synchronous demodulation with active carrier regeneration (very linear demodulation, 

good intermodulation figures, reduced harmonics, excellent pulse response) 
Gated phase detector for L/L accent standard 
Fully integrated VIF Voltage Controlled Oscillator (VCO), alignment-free; frequencies switchable for all 
negative and positive modulated standards via I

2

C-bus  

Digital acquisition help, VIF frequencies of 33.4, 33.9, 38.0, 38.9, 45.75 and 58.75 MHz 
4 MHz reference frequency input [signal from Phase-Locked Loop (PLL) tuning system] or operating as 
crystal oscillator 
VIF Automatic Gain Control (AGC) detector for gain control, operating as peak sync detector for negative 
modulated signals and as a peak white detector for positive modulated signals 
Precise fully digital Automatic Frequency Control (AFC) detector with 4-bit digital-to-analog converter; AFC 
bits via I

2

C -bus readable 

TakeOver Point (TOP) adjustable via I

2

C-bus or alternatively with potentiometer 

Fully integrated sound carrier trap for 4.5, 5.5, 6.0 and 6.5 MHz, controlled by FM-PLL oscillator 
Sound IF (SIF) input for single reference Quasi Split Sound (QSS) mode (PLL controlled)