ILC7526-IK Impala Linear Corporation, ILC7526-IK Datasheet - Page 4

• Manufacturer Part Number: ILC7526-IK
• Description: USB DUAL CONTROL SWITCHES
• Manufacturer: Impala Linear Corporation

Note 1. Stresses above those listed under ABSOLUTE MAXIMUM RAT-
INGS may cause permanent device failure.
these limits is not implied. Exposure to absolute maximum ratings for
extended periods may affect device reliability. Operating ranges define
those limits between which the functionality of the device is guaranteed.
Note 2. Specified min/max limits are production tested or guaranteed
The ILC7526 and ILC7536 are dual high-side switches with
active-high and active-low enable inputs, respectively.
Fault conditions turn-off or inhibit turn-on of one or more of
the output transistors, depending upon the type of fault,
and also activate the open-drain error flag transistors
which sink current to ground.
Input and Output
IN (input) is the power supply connection to the logic circuit-
ry and the drains of both of the output MOSFET’s. OUTx
(output) is the source of each MOSFET. In a typical circuit,
current flows through the switch from IN to OUT toward the
load. If V
current will flow from OUT to IN since the MOSFET is bidi-
rectional when on.
The output MOSFET and driver circuitry are also designed to
allow the MOSFET source to be externally forced to a higher
voltage than the drain (V
this situation, the ILC7526 avoids undesirable current flow
from OUT to IN. If V
ILC7526/7536 1.5
Functional Description
USB Dual Control Switches
Impala Linear Corporation
OUT
is greater than V
IN
< 2.5V, UVLO disables both switches.
OUT
> V
5V
IN
IN
10k
) when the output is off. In
when a switch is enabled,
Functionality at or above
0.1µF
[phone]
FLGA
FLGB
ENB
ENA
ILC7526
OUTA
OutB
GND
IN
through correlation based on statistical control methods. Measurements
are taken at constant junction temperature as close to ambient as possible
using low duty pulse testing.
Note 3. Off is < 0.8V and On is > 2.4V for the ILC7526. Off is > 2.4V for
the ILC7536. The enable input has approximately 200mV of hysteresis.
Thermal Shutdown
Thermal shutdown shuts off the affected output MOSFET’s
and signals all fault flags if the die temperature exceeds
135°C. 10°C of hysteresis prevents the switch from turn-
ing on until the die temperature drops to 125°C.
Overtemperature detection functions only when at least
one switch is enabled.
Internal circuitry increases the output MOSFET on-resist-
ance until the series combination of the MOSFET on-resist-
ance and the load impedance limit current to typically
850mA. The increase in power dissipation, in most cases,
will cause the ILC7526 to go into thermal shutdown, dis-
abling affected channels. When this is undesirable, thermal
shutdown can be avoided by externally responding to the
fault and disabling the current limited channel before the
shutdown temperature is reached. The delay between the
flag indication of a current limit fault and thermal shutdown
will vary with ambient temperature, board layout, and load
impedance, but is typically several hundred milliseconds.
The USB controller must therefore recognize a fault and
disable the appropriate channel within this time. If the fault
is not removed or the switch is not disabled within this time,
the device will enter into a thermal oscillation of about 2Hz.
This does not cause any damage to the device.
Current Limit Induced Thermal Shutdown
www.impalalinear.com
I
OUT
C
L
+
(1 output shown)
R
L
Dec 2000
Preliminary
4