xc9509c03cdr TOREX SEMICONDUCTOR LTD., xc9509c03cdr Datasheet - Page 11

• Manufacturer Part Number: xc9509c03cdr
• Description: Xc9509 Synchronous Step-down Dc/dc Converter With Built-in Ldo Regulator In Parallel Plus Voltage Detector
• Manufacturer: TOREX SEMICONDUCTOR LTD.

■NOTES ON USE
●DC/DC Waveform (3.3V, 1.2MHz)
●Application Information
■OPERATIONAL EXPLANATION (Continued)
●Voltage Detector
1. The XC9509 series is designed for use with a ceramic output capacitor. If, however, the potential difference
2.
3. When the difference between V
4. When the difference between V
<MODE Pin Function>
The detector block of the XC9509 series detects output voltage from the V
V
(N-channel Open Drain Type)
<CE Pin Function>
The operation of the XC9509 series' DC/DC converter block and voltage regulator block will enter into the shut down
mode when a low level signal is input to the CE pin. During the shut down mode, the current consumption occurs only
in the detector and is 3.0μA (TYP.), with a state of high impedance at the Lx pin and the D
operation by inputting a high level signal to the CE pin. The input to the CE pin is a CMOS input and the sink current is
0μA (TYP.).
The operation of the XC9509A to C series' voltage detector block will enter into stand-by mode when a high level signal is
input to the MODE pin. When a low level signal is input, the voltage regulator block will enter into stand-by mode.
However, if the IC enters into stand-by mode via the CE pin, the voltage regulator block also shuts down. Likewise, if
the XC9509D to F series enters into stand-by mode via the CE pin, the DC/DC converter block can also shut down.
With the XC9509H to L series control can be PWM control when the MODE pin is 'H' level and PWM/PFM automatic
switching control when the MODE pin is 'L' level.
ROUT
between dropout voltage or output current is too large, a ceramic capacitor may fail to absorb the resulting high
switching energy and oscillation could occur on the output. If the input-output potential difference is large, connect
an electrolytic capacitor in parallel to compensate for insufficient capacitance.
influenced by external component selection, such as the coil inductance, capacitance values, and board layout of
external components. Once the design has been completed, verification with actual components should be done.
is the possibility that some cycles may be skipped completely.
and there is the possibility that some cycles may be skipped completely: in this case, the Lx pin may not go low at all.
Spike noise and ripple voltage arise in a switching regulator as with a DC/DC converter.
internally.
<External Components>
L
CIN
CL
:4.7μH(CDRH4D28C,SUMIDA)
:4.7μF(ceramic)
:10μF(ceramic)
IN
IN
and V
and V
OUT
OUT
is small, and the load current is heavy, very wide pulses will be outputted
is large in PWM control, very narrow pulses will be outputted, and there
<External Components>
L
CIN
CL
DOUT
<External Components>
L
CIN
CL
:4.7μH(CDRH4D28C,SUMIDA)
:4.7μF(ceramic)
:10μF(ceramic)
pin while sensing either V
:4.7μH(CDRH4D28C,SUMIDA)
:4.7μF(ceramic)
:10μF(ceramic)
COUT
pin. The IC starts its
These are greatly
DD
, D
XC9509
COUT
11/41
Series
, or