XC6204/XC6205 Series
■OPERATIONAL EXPLANATION (Continued)
<Current Limiter, Short-Circuit Protection>
The XC6204/05 series includes a combination of a fixed current limiter circuit & a foldback circuit, which aid the operations of
the current limiter and circuit protection. When the load current reaches the current limit level, the fixed current limiter circuit
operates and output voltage drops. As a result of this drop in output voltage, the foldback circuit operates, output voltage
drops further and output current decreases. When the output pin is shorted, a current of about 50mA flows. However, when
the input/output voltage differential is quite small, this current will be about 200mA.
<CE Pin>
The IC's internal circuitry can be shutdown via the signal from the CE pin with the XC6204/05 series. In shutdown mode,
output at the VOUT pin will be pulled down to the VSS level via R1 & R2. The operational logic of the IC's CE pin is selectable
(please refer to the selection guide). Note that as the standard XC6204/05B type is ' High Active/No Pull Down', operations
will become unstable with the CE pin open. Although the CE pin is equal to an inverter input with CMOS hysteresis, with
either the pull-up or pull-down options, the CE pin input current will increase when the IC is in operation.
We suggest that you use this IC with either a VIN voltage or a VSS voltage input at the CE pin. If this IC is used with the
correct specifications for the CE pin, the operational logic is fixed and the IC will operate normally. However, supply current
may increase as a result of through current in the IC's internal circuitry if a voltage between 0.25V and 1.5V is input.
<Minimum Operating Voltage>
In order to stabilize the IC's operations, an input voltage of more than 2.0V is needed. Should the input voltage be less
than 2.0V, the output voltage may not be regulated correctly. (Please refer to Input Voltage vs. Output Voltage
characteristics below.)
①
When VIN is less than 2.0V, the CE pin remains in stand-by mode.
When VIN rises above 2.0V, the power supply will turn ON.
The input power supply will begin to rise after a few hundred msec.
(Please also refer to the transient response characteristics.)
②
○ Input Voltage vs. Output Voltage
○ Enable Response Time
○ Turn-ON Response Time
18/49
TOREX [ Torex Semiconductor ]
