XC61C
Series
■Directions for use
GNotes
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 stabilise 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.
2
XC61CN Series
R
IN
V
IN
C
V
SS
V
OUT
GOscillation
Description
(1) Output current oscillation with the CMOS output configuration
Diagram: Circuit using an input resistor
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 diagram 2 )
Since hysteresis exists during detect operations, oscillation is unlikely to occur.
IN
IN
R
IN
R
IN x
I
OUT
Voltage Drop
XC61CC Series
R
IN
x I
SS
Voltage Drop
R
IN
XC61CC Series
XC61CN Series
V
IN
V
SS
V
OUT
I
OUT
V
IN
V
SS
V
OUT
R
L
I
SS
*
（Includes Current）
Diagram 1: Oscillation in relation to output current
Diagram 2: Oscillation in relation to through current
139
TOREX [ TOREX SEMICONDUCTOR ]
