AP2411S-13 Diodes Inc., AP2411S-13 Datasheet - Page 10

• Manufacturer Part Number: AP2411S-13
• Description: Power Switch ICs - USB USB Power Switch Switch,SO-8,2.5K
• Manufacturer: Diodes Inc.

Specifications of AP2411S-13

• Product Category: Power Switch ICs - USB
• Rohs: yes
• Supply Voltage - Min: 2.7 V
• Supply Voltage - Max: 5.5 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Package / Case: SO-8
• Number Of Switches: Single
• Supply Current: 2 A

Application Information
Power Supply Considerations
A 0.1μF to 2.2μF X7R or X5R ceramic bypass capacitor placed between IN and GND, close to the device, is recommended. When an external
power supply is used, or an additional ferrite bead is added to the input, high inrush current may cause voltage spikes higher than the device
maximum input rating during short circuit condition. In this case a 2.2μF or bigger capacitor is recommended. Placing a high-value electrolytic
capacitor on the input and output pin(s) is recommended when the output load is heavy. This precaution reduces power-supply transients that
may cause ringing on the input. Additionally, bypassing the output with a 0.1μF to 1.0μF ceramic capacitor improves the immunity of the device
to short circuit transients.
Over-Current and Short Circuit Protection
An internal sensing FET is employed to check for over-current conditions. Unlike current-sense resistors, sense FETs do not increase the series
resistance of the current path. When an overcurrent condition is detected, the devices will limit the current until the overload condition is removed
or the internal deglitch time (7-ms typical) is reached and the device is turned off. The device will remain latched off even overload condition is
removed until power is cycled or the device enable is toggled.
Three possible overload conditions can occur. In the first condition, the output has been shorted to GND before the device is enabled or before
VIN has been applied. The AP2401/AP2411 senses the short circuit and immediately clamps output current to a certain safe level namely I
and turns off after deglitch time(7-ms typical).
In the second condition, an output short or an overload occurs while the device is enabled. At the instance the overload occurs, higher current
may flow for a very short period of time before the current limit function can react. After the current limit function has tripped (reached the
over-current trip threshold), the device switches into current limiting mode and the current is clamped at I
(7-ms typical), and then turned off.
In the third condition, the load has been gradually increased beyond the recommended operating current. The current is permitted to rise until the
current-limit threshold (I
up to the current-limit threshold without damaging the device. Once the threshold has been reached, the device switches into its current limiting
mode and output current is clamped at I
FLG Response
When an over-current or over-temperature shutdown condition is encountered, the FLG open-drain output goes active low after a nominal 7-ms
deglitch timeout.
When that happens, the FLG will remain low and the switch will be latched off until the fault condition is removed. Connecting a heavy capacitive
load to the output of the device can cause a momentary over-current condition, which does not trigger the FLG due to the 7-ms deglitch timeout.
The AP2401/AP2411 is designed to eliminate false over-current reporting without the need of external components to remove unwanted pulses.
Power Dissipation and Junction Temperature
The low on-resistance of the internal MOSFET allows the small surface-mount packages to pass large current. Using the maximum operating
ambient temperature (TA) and R
Finally, calculate the junction temperature:
Where:
Thermal Protection
Thermal protection prevents the IC from damage when heavy-overload or short-circuit faults are present for extended periods of time. The
AP2401/AP2411 implements a thermal sensing to monitor the operating junction temperature of the power distribution switch. Once the die
temperature rises to approximately +140°C due to excessive power dissipation in an over-current condition, the internal thermal sense circuitry
turns the power switch off, thus preventing the power switch from damage. Hysteresis is built into the thermal sense circuit allowing the device to
cool down approximately +25°C before the switch turns back on. The switch continues to cycle in this manner until the load fault or input power is
removed. The FLG open-drain output is asserted when an over-temperature shutdown occurs with 7-ms deglitch.
When the FLG is asserted, the switch will be latched off until the temperature drops to 20°C below the thermal shutdown threshold and the power
or EN pin is cycled.
AP2401/AP2411
Document number: DS35113 Rev. 6 - 2
P
T
T
R
P
J
A
D
D
 JA
= Ambient temperature°C
= P
= R
= Total power dissipation
= Thermal resistance
D
DS(ON)×
x R
 JA
I
2
+ T
TRIG
A
) is reached or until the thermal limit of the device is exceeded. The AP2401/AP2411 is capable of delivering current
DS(ON),
the power dissipation can be calculated by:
LIMIT
for deglitch time period (7-ms typical), and then turned off.
www.diodes.com
10 of 18
LIMIT
current for deglitch time period
AP2401/AP2411
© Diodes Incorporated
March 2013
LIMIT
,