XC61F
Series
■DIRECTIONS
FOR USE
●Notes
on Use
1. Please use this IC within the stated maximum ratings. The IC is liable to malfunction should the ratings be exceeded.
2. When a resistor is connected between the V
IN
pin and the input with CMOS output configurations, oscillation may
occur as a result of voltage drops at R
IN
if load current (I
OUT
) exists. It is therefore recommend that no resistor be added.
(refer to Oscillation Description (1) below)
3. When a resistor is connected between the V
IN
pin and the input with CMOS output configurations, irrespective of N-ch
output configurations, oscillation may occur as a result of through current at the time of voltage release even if load
current (I
OUT
) does not exist. (refer to Oscillation Description (2) below)
4. With a resistor connected between the V
IN
pin and the input, detect and release voltage will rise as a result of the IC's
supply current flowing through the V
IN
pin.
5. If a resistor (R
IN
) must be used, then please use with as small a level of input impedance as possible in order to control
the occurrences of oscillation as described above.
Further, please ensure that R
IN
is less than 10kΩ and that C
IN
is more than 0.1μF (Figure 1). In such cases, detect
and release voltages will rise due to voltage drops at R
IN
brought about by the IC's supply current.
●Oscillation
Description
(1) Oscillation as a result of output current with the CMOS output configuration:
When the voltage applied at IN rises, release operations commence and the detector's output voltage increases. Load
current (I
OUT
) will flow through R
L
. Because a voltage drop (R
IN
x I
OUT
) is produced at the R
IN
resistor, located
between the input (IN) and the V
IN
pin, the load current will flow via the IC's V
IN
pin. The voltage drop will also lead to
a fall in the voltage level at the V
IN
pin. When the V
IN
pin voltage level falls below the detect voltage level, detect
operations will commence. Following detect operations, load current flow will cease and since voltage drop at R
IN
will
disappear, the voltage level at the V
IN
pin will rise and release operations will begin over again.
Oscillation may occur with this " release - detect - release " repetition.
Further, this condition will also appear via means of a similar mechanism during detect operations.
(2) Oscillation as a result of through current:
Since the XC61F series are CMOS IC
S
, through current will flow when the IC's internal circuit switching operates
(during release and detect operations). Consequently, oscillation is liable to occur during release voltage operations
as a result of output current which is influenced by this through current (Figure 3).
Since hysteresis exists during detect operations, oscillation is unlikely to occur.
Figure 1. When using an input resistor
6/14
TOREX [ TOREX SEMICONDUCTOR ]
