lc78684e Sanyo Semiconductor Corporation, lc78684e Datasheet - Page 20

• Manufacturer Part Number: lc78684e
• Description: Mp3 Decoder For Compact Disc Players
• Manufacturer: Sanyo Semiconductor Corporation

Application Design Notes
While it goes without saying that strictly observing the absolute maximum ratings and allowable operating ranges
(recommended operation conditions) stipulated for this IC is necessary to achieve reliability of the overall system, it is also
necessary to take adequate care with respect to the mounting conditions and the operating environment, including the ambient
temperature and the possibility of electrostatic discharges (ESD). This section presents notes on aspects of design and
mounting that require special attention.
Handling Unused Pins
If this IC is operated with unused input pins left open, certain internal circuit operations may become unstable. Unused pins
that are mentioned in the IC documentation must be handled as specified. Also, do not allow output pins to come in contact
with any circuit lines, including power supply lines, ground lines, or other outputs.
Latchup Prevention
x The voltages stipulated in the IC specifications must be provided to the corresponding power supply pins. When the same
x Do not set I/O voltage levels to be either higher than the peripheral 3 V system block voltage, or lower than the ground
x Do not apply overvoltages or abnormal noise to this IC.
x While in general, latchup is prevented by holding unused input pins at either the VDD or VSS potential, input pins to this IC
x Do not short the outputs.
Interface
Incorrect operation may result when different devices are connected if the input VIL/VIH and the output VOH and VOH
levels do not match. Level shifters must be inserted between devices with differing supply voltages, such as those often used
in dual power supply systems, to prevent destruction of the devices.
Load Capacitance and Output Current
x If a large load capacitance is connected, the resulting effective short of the outputs may continue for an extended period and
x Excessive output sink or source currents can lead to the same problems described in the preceding item. Once the allowable
Notes on Power Application and Reset
x There are several aspects that require care when power is first applied, during a reset, and when the reset state is cleared.
x In this IC, the register contents, pin output states, and pin I/O settings are not guaranteed after power is first applied. Items
Thermal Design
x Semiconductor device failure rates are greatly accelerated by inappropriate ambient temperature and power consumption
voltage is stipulated for multiple pins, those pins all must be connected to the same potential.
level. This relationship must also be maintained during the power-on sequence.
must be handled as described in the pin descriptions.
lead to fusing of lines. Also, larger charge and discharge currents can cause noise, degrade device performance, and cause
incorrect operation. The recommended load capacitance ratings must be observed.
power dissipation rating has been met, the recommended current values must be observed as well.
Refer to the device specifications and design applications to match the product specifications.
that are defined by the reset operation or mode setting operations are guaranteed after these operations are performed. After
power is first applied to this IC, the application must first perform a reset operation. Pin states and register values that are
not defined are subject to change, both due to sample-to-sample variations in the product over the long term, and due to
changes in device design from the initial design states.
conditions. To assure the highest possible reliability, the thermal design should provide ample margins considering all
possible changes in the ambient conditions.
LC78684E
No.7350-20/21