XC9515AA01ZL TOREX [Torex Semiconductor], XC9515AA01ZL Datasheet - Page 12

• Manufacturer Part Number: XC9515AA01ZL
• Description: 2 channel Synchronous Step-Down DC/DC Converter with Manual Reset
• Manufacturer: TOREX [Torex Semiconductor]

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■NOTES ON USE
1.
2.
3.
4.
5.
6. Since the potential difference for input voltage has occurred to the both ends of a coil, the time changing rate of the coil
XC9515
This operation is repeated and the delay time of the circuit also influences, therefore, the coil current is converged on the
current value beyond the amount of current which should be restricted essentially.
The short-circuit protection does not operate during the soft-start time.
short-circuit protection starts to operate and the circuit becomes disable.
The delay time of the circuit also influences when step-down ratio is large, as the result, a current more than over current
limit may flow. Please do not exceed the absolute maximum ratings of the coil.
① A current flows to the driver transistor up to the current limit (I
② For the delay time of the circuit, a current more than the I
③ Time changing rate of the coil current becomes very small because there is no potential difference between both ends
④ The Lx pin oscillates a narrow pulse during the soft-start time because of the current limit.
⑤ The circuit is latched since the short-circuit protection operates and the P-channel driver transistor is turned off.
Please use this IC within the stated maximum ratings. The IC is liable to malfunction should the ratings be exceeded.
Please apply the same electrical potential to the P_V
P_V
causes malfunction. Also the same electrical potential should be applied to the P_V
The XC9515 series is designed for use with ceramic output capacitors. If, however, the potential difference between
dropout voltage or output current is too large, a ceramic capacitor may fail to absorb the resulting high switching energy and
the output could be unstable. If the input-output potential difference is large, use a larger output capacitor to compensate for
insufficient capacitance.
When the peak current, which exceeds limit current flows within the specified time, the built-in driver transistor is turned off
(the integral latch circuit). During the time until it detects limit current and before the built-in transistor can be turned off, the
current for limit current flows; therefore, care must be taken when selecting the rating for the coil.
When the input voltage is low, limit current may not be reached because of voltage falls caused by ON resistance or serial
resistance of the coil.
current is large when the P-channel driver transistor is ON. On the other hand, since the V
when the N-channel transistor is ON and there is almost no potential difference of the coil both ends, the time changing rate
of the coil current becomes very small.
transistor turns off.
of the coil.
DD1
and P_V
DD2
Series
pins should have the same electrical potential. Applying the electrical potential to only one side
DD1
and P_V
LIM
LIM
DD2
).
flows after the I
pins. Even where either CH1 or CH2 is used, both
# ms
As soon as the soft-start time finishes, the
SS1
LIM
, P_V
decide until the P channel driver
OUT
SS2
pin short-circuits to the GND
and A_V
SS
pins.