XC6404 Datasheet, PDF (26/54 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)
<Toggle Operation> (Continued)
For the XC6404B series, there are two types of toggle selection; one is a T-type flip-flop (T-FF) used for toggle operation which can be reset internally by
a signal directly from the voltage detector (VIN Sense type only. See also the Selection Guide on page 2). The other type is where the reset is applied
internally through a one shot pulse circuit (VIN, VROUT type only. See also the Selection Guide on page 2).
The type, which applies the reset directly via the signal from the voltage detector function, applies the voltage detector comparator's output signal (reset
signal) to the reset of T-FF reset, and turns the VR output OFF when the input voltage decreases below the detect voltage due to battery consumption,
etc.. In order to return the VR output, apply a voltage larger than the release voltage to VIN and input a toggle signal to the T-FF. In the case where
input voltage is below the release voltage, the VR output does not return even though the toggle signal is input into the T-FF.
The type which applies the reset signal to the T-FF internally via a one-shot pulse circuit changes the voltage detector comparator output signal to a one-
shot signal internally. Like the type which applies the reset directly via the signal from voltage detector function, this type also applies the reset to the T-
FF and sets the VR output to OFF when the input voltage (VIN Sense type) and output voltage (VROUT Sense type) drop below the detect voltage level.
This type can return the VR output by inputting a toggle signal, even when the Sense pin voltage (VIN or VROUT pin voltage) is below the release
voltage.
Please refer to the block diagram below and the timing chart on the following page. Please choose the option suitable to the application.
EN
Optional
VDOUT
D
ON/OFF
control
Toggle Signal
toggle FF
TQ
R
VR circuit
T-FF Reset Signal
B
C
1 Shot
Pulse
Current
limit
Error Amp. _{CFB R2}
Power ON
Clear for FF
R1
Voltage
Reference
F
R4
Comp. VD
R3
Block Diagram for XC6404B series Timing Chart
A
VIN
E
VROUT
Optional
VSS
Data Sheet
26
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