XC6404 Datasheet, PDF (25/54 Pages) Torex Semiconductor – High Current, High Speed LDO Regulators, Voltage Detector Function

XC6404 Series
High Current, High Speed LDO Regulators, Voltage Detector Function
! OPERATIONAL EXPLANATION (Continued)
<EN / CE Pin>
The IC's internal regulator circuitry can be shut down via the signal from the EN pin with the XC6404A, B, C series. In shutdown mode, output at the
VROUT pin will be pulled down to the VSS level via R1 & R2. The whole IC's circuitry can be shut down via CE pin with the XC6404D series and power
consumption can be reduced to around 0 µA. While the voltage detector is in shutdown mode, the voltage detector output is in a post-detection state.
When choosing Detect L, input current can be set by using the following formula.
Input Current = VIN voltage / Pull Up Resistance
In stand-by mode, the above input current can be reduced by connecting a pull-up resistor between VROUT and VDOUT.
Note that as the XC6404*E to K types of the XC6404A to D series are 'Active HIGH / No Pull Down' and XC6404*R to U types of the XC6404A to D
series are 'Active LOW / No Pull Up', operations will become unstable with the CE pin open (See the chart below).
SERIES
XC6404 * A ~ D
XC6404 * E ~ K
XC6404 * L ~ P
XC6404 * R ~ U
EN/CE INPUT LOGIC
Active HIGH with pull down
Active HIGH with no pull down
Active LOW with pull up
Active LOW with no pull up
( * A ~ D Series)
We suggest that you use this IC with either a VIN voltage or a VSS voltage input at the EN or CE pin. If this IC is used with the correct specifications for
the EN or CE pin, 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 other than VIN or VSS is applied.
<Toggle Operation>
The XC6404 A and B series have a built-in toggle ON/OFF switch which repeats an on/off operation via the EN pin's leading edge signal when the EN
logic is Active HIGH, and via the EN pin's falling edge signal when the EN logic is Active LOW (Please also refer the figure below). The EN input signal
duration should be over 500nsec. If the EN input signal is less than 500nsec, it is possible that the circuit fails to respond and the toggle function does
not operate. To operate the toggle function properly when the EN pin voltage noise is large, a RC filter should be used to reduce the noise in the signal
to the EN pin. In the case where input delay time is required, it is possible to set the time constant by connecting an RC network to the EN pin.
Data Sheet
VIN
CIN
1uF
VIN EN
VSS
VROUT
VDOUT
CL
1uF
Internal Circuit - Response time
apporx. 10usec.
1.5kΩ
0.1uF
Rpull
220kΩ
VROUT Voltage
VROUT Voltage
GND
VIN Voltage
More than
500nsec
EN pin signal
GND
EN Logic Active "HIGH"
25
Semiconductor Ltd.