HT7704
Touc h Dim mer
Pin Assignment Pad Assignment
Feature
•Operating voltage: 4~ 10V
•High noise immunity CMOS technology
•High sensitivity and stability
•Polarity insensitive with AC line
•Minimal external compon ents required
•Loading range of sense input from 0 t o 1000pf
•50/60 Hz selectable
•HT7704A: 3 steps control
HT7704B: 4 steps control
HT7704 C: On/off switch
•8 pin DIP/SOP package
General Description
The HT7704 series are CMOS LSIs in 8-lead DIP
package. They are designed to control the bright-
ness of an incandescent lamp by changing the
triggering angles of the TRIAC with touch sense
input.
HT7704 is a selectable 3-step, 4-step or on/off
switch function dimmer. High sensitivity and
stability account for its eminent performance.
The se nse input can sustain very heavy capaci-
tive loading and propagate sense through a
highly resistive line. In addition, the applica-
tion circuit is very simple.
Chip size: 1640 × 1620 (µm)2
* The IC substrate should be connected to VSS
in the PCB layout artwork.
1 27th Dec ’96
Block Diagram
Pad Coordinates Unit: µm
Pad No. X Y Pad No. X Y
1 –563.75 373 7 604.75 –122
2 –557.25 166 8 594.25 230.5
3 –563.75 –91 9 595.25 544.5
4 –198.25 –544 10 –308.25 573.5
5 171.25 –544 11 –641.75 573.5
6 604.75 –297
Pin Description
Pin No. Pin Name I/O Internal
Connection Description
1 OSC I ∗Oscillator input
2 ZC I CMOS Line frequency 50Hz or 60Hz input for zero cro ss ing
3 VDD I — Power supply (positive)
4SENSE I∗Touch sense input
5FB I ∗Feedback signal to control the sink current of the
SENSE pin.
6 FSEL I CMOS
For 50Hz or 60Hz AC signal selection input
It is connected to VSS when the AC line is 50Hz.
However, when the AC line is 60Hz, it is connected to
VDD. Refer to the application circuit for connection
details.
7 VSS I — Power su pply (negative)
8TRIG1 O CMOS Trigger output to drive the TRIAC
Low pulse output with a capacitor and resistors for
applications
HT7704
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Approx i mat e i nte r na l co nn ec t ion circuit
Absolute Maximum Ratings
Supply Voltage...............................–0.3V to 12V Input Voltage..................VSS–0.3V to VDD+0.3V
Operating Temperature...................0°C to 70°CStorage Temperature............. ....–50°C to 125°C
Electrical Characteristics (Ta=25°C)
Symbol Parameter Test Condition Min. Type Max. Unit
VDD Condition
VDD Operating Voltage — — 4 7 10 V
IDD Operating Current 7V *— 200 400 µA
IIH OPT1, OPT2 Input
High Current 7V VIH=7V — 40 80 µA
IOL1 TRIG1 Sink Current 7V VOL=0.7V 0.4 0.7 — mA
IOH1 TRIG1 Drive Current 7V VOH=6.3V –8 –14 — mA
IOL2 TRIG2 Sink Current 7 V VOL=0.7V 6 11 — mA
IOH2 TRIG2 Drive Current 7V VOH=6.3V –1 –2 — mA
VIH Input High Voltage — —0.8VDD —— V
V
IL Input Low Voltage — —— — 0.2VDD V
FOSC O per at i ng Fr eq ue ncy 7V ROSC=150KΩ—400 — KHz
* The test conditions are shown below:
a. ZC is supplied by 60Hz/7V sinwave via 100KΩ.
b. FB is connected to VSS and SENSE, FSEL to VDD.
HT7704
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Functional Description
Sel ect i on tabl e
There are 3 types of HT7704 and the following table illustrates their operating mode:
IC No. O PT1 OPT2 Function
HT7704A Open Open 3 steps of controllable brightness
HT7704B Open Bond to VDD 4 steps of controllable brightness
HT7704C Bond to VDD Open On/off the light
Flow Chart
•3 steps (for the HT7704A)
The first touch turns the light on at it’s initial
brightness level. The second touch makes the
light a little brighter . The light is the brightest by
the third touch. Finally, the fourth touch turns
the light off.
•4 steps (for the HT7704B)
Similarly with the 4-step. The first touch tuns
the light on at it’ s initial brightness level. The
second touch makes the light brighter. The
brightness increases greatly on the third
touch an d rea che s it’s brightest o n th e fourth
touch, respectively. Finally the fifth touch
switches the light off.
HT7704
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Timing Diagram
3 steps trigger angle (FOSC=400KHz)
•ON/OFF switch (for the HT7704C)
The initial touch turns the light on. When touched again, the light is turned off, and so on.
TRIAC
(T rig g er a ngle=86.4
°
)
TRIAC
(Trig ger angle=17.28
°
)
TRIG1
TRIG2
TRIG1
TRIG2
TRIG1
TRIAC
(Trigger angle=120.96
°
)
TRIG2
TR IAC turns onTR IAC turns off
HT7704
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4 steps trigger angle (FOSC=400KHz)
TRIAC
(Trigge r an gle=95.04
°
)
TRIG1
TRIG2
TRIAC
(Trigge r an gle=69.12
°
)
TRIG1
TRIG2
TRIAC
(Trigge r an gle=17.28
°
)
TRIG1
TRIG2
TRIG1
TRIAC
(T rigg er ang le=129.6
°
)
TRIG2
TR IAC turns onTR IAC turns off
HT7704
6 27th Dec ’96
On/off trigger angle (FOSC=400KHz)
Applicatio n Circuit
Pack ag e form
TRIAC
(Trigge r angle=17.28
°
)
TRIG1
TRIG2
HT7704
7 27th Dec ’96
