XC61C
Series
■NOTES
ON USE
1. Please use this IC within the stated maximum ratings. Operation beyond these limits may cause degrading or permanent
damage to the device.
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. (refer to the 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 the 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. In order to stabilize the IC's operations, please ensure that V
IN
pin's input frequency's rise and fall times are more than
several µ sec / V.
6. Please use N-ch open drains configuration, when a resistor R
IN
is connected between the V
IN
pin and power source.
In such cases, please ensure that R
IN
is less than 10kΩ and that C is more than 0.1µF.
●Oscillation
Description
(1) Output current oscillation 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 at 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 XC61C 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 as a result of drops in voltage at the through
current's resistor (R
IN
) during release voltage operations. (refer to Figure 3)
Since hysteresis exists during detect operations, oscillation is unlikely to occur.
11/19
TOREX [ TOREX SEMICONDUCTOR ]
