LA7567GM Datasheet, PDF (14/14 Pages) Sanyo Semicon Device – TV and VCR VIF/SIF IF Signal-Processing Circuit with NTSC SPLIT Support

LA7567GM
Notes on VCO Tank Circuits
• Built-in capacitor VCO tank circuits
When the power is turned on, the heat generated by the IC is transmitted through the printed circuit board to the VCO
tank circuit. At this point, the VCO coil frame functions as a heat sink and the IC heat is dissipated. As a result, it
becomes more difficult to transmit heat to the VCO tank circuit's built-in capacitor, and the influence of drift at power
on is reduced. Therefore, it suffices to design the circuit so that the coil and capacitor thermal characteristics cancel.
Ideally, it is better to use a coil with a core material that has low temperature coefficient characteristics.
• External capacitor VCO tank circuits
When an external capacitor is used, heat generated by the IC is transmitted through the printed circuit board directly to
the VCO tank circuit external capacitor. While this capacitor is heated relatively early after the power is turned on, the
coil is not so influenced as much by this heat, and as a result the power-on drift is increased. Accordingly, a coil whose
core material has low temperature coefficient characteristics must be used. It is also desirable to use a capacitor with
similarly low temperature coefficient characteristics.
Note: Applications that use an external capacitor here must use a chip capacitor. If an ordinary capacitor is used,
problems such as the oscillator frequency changing with the capacitor orientation may occur.
Specifications of any and all SANYO products described or contained herein stipulate the performance,
characteristics, and functions of the described products in the independent state, and are not guarantees
of the performance, characteristics, and functions of the described products as mounted in the customer’s
products or equipment. To verify symptoms and states that cannot be evaluated in an independent device,
the customer should always evaluate and test devices mounted in the customer’s products or equipment.
SANYO Electric Co., Ltd. strives to supply high-quality high-reliability products. However, any and all
semiconductor products fail with some probability. It is possible that these probabilistic failures could
give rise to accidents or events that could endanger human lives, that could give rise to smoke or fire,
or that could cause damage to other property. When designing equipment, adopt safety measures so
that these kinds of accidents or events cannot occur. Such measures include but are not limited to protective
circuits and error prevention circuits for safe design, redundant design, and structural design.
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herein are controlled under any of applicable local export control laws and regulations, such products must
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above law.
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or otherwise, without the prior written permission of SANYO Electric Co., Ltd.
Any and all information described or contained herein are subject to change without notice due to
product/technology improvement, etc. When designing equipment, refer to the “Delivery Specification”
for the SANYO product that you intend to use.
Information (including circuit diagrams and circuit parameters) herein is for example only; it is not
guaranteed for volume production. SANYO believes information herein is accurate and reliable, but
no guarantees are made or implied regarding its use or any infringements of intellectual property rights
or other rights of third parties.
This catalog provides information as of December, 2001. Specifications and information herein are
subject to change without notice.
PS No. 6803-14/14