MAX4788EXS+T Maxim Integrated Products, MAX4788EXS+T Datasheet - Page 6

• Manufacturer Part Number: MAX4788EXS+T
• Description: IC SWITCH 1X1 SC70-4
• Manufacturer: Maxim Integrated Products

Specifications of MAX4788EXS+T

• Function: Switch
• Circuit: 1 x 1:1
• On-state Resistance: 1 Ohm
• Voltage Supply Source: Single Supply
• Voltage - Supply, Single/dual (±): 2.3 V ~ 5.5 V
• Current - Supply: 65µA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: SC-70-4, SC-82-4, SOT-323-4, SOT-343
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: MAX4788EXS+T; MAX4788EXS+TTR

The MAX4785–MAX4788 are forward/reverse current-
limited switches that operate from a 2.3V to 5.5V input
voltage range and guarantee a 50mA and 100mA mini-
mum current-limit threshold for different options. The
voltage drop across an internal sense resistor is com-
pared to two reference voltages to indicate a forward or
reverse current-limit fault. When the load current
exceeds the preset current limit for greater than the
fault-blanking time, the switch opens.
The MAX4786 and MAX4788 have an autoretry function
that turns on the switch again after an internal retry time
expires. If the faulty load condition is still present after
the blanking time, the switch turns off again and the
cycle is repeated. If the faulty load condition is not pre-
sent, the switch remains on.
The MAX4785 and MAX4787 do not have the autoretry
option and the switch remains in latch-off mode until
the ON pin or the input power is cycled from high to low
and then high again.
The undervoltage lockout (UVLO) circuit prevents erro-
neous switch operation when the input voltage goes too
low during startup conditions.
50mA/100mA Current-Limit Switches
Figure 1. MAX4785–MAX4788 Functional Diagram
6
_______________________________________________________________________________________
ON
IN
AUTO-
RETRY
LOGIC
Detailed Description
UNDERVOLTAGE
LOCKOUT
+2.0V
REVERSE-CURRENT
FORWARD CURRENT
DETECTOR
DETECTOR
The MAX4785–MAX4788 limit the reverse current (V
to V
switch is shut off and FLAG is asserted (MAX4785/
MAX4787) if the reverse current-limit condition persists
for more than the blanking time. This feature prevents
excessive reverse currents from flowing through the
device.
Toggle ON high to enable the current-limited switches.
The switches are continuously on, only if V
the UVLO threshold (typically 2V) and there is no fault.
When a forward/reverse current fault is preset or the die
exceeds the thermal-shutdown temperature of +150°C,
OUT is internally disconnected from IN and the supply
current decreases to 8µA (latch off). The switch is now
operating in one of its off states. The switch off-state
also occurs when driving ON low, thus reducing the
supply current (shutdown) to 0.01µA. Table 1 illustrates
the ON/OFF state of the MAX4785–MAX4788 current-
limit switches.
IN
) from exceeding the maximum I
MAX4785–MAX4788
BLANKING TIME
CIRCUITRY
Reverse-Current Protection
MAX4785/MAX4787
Switch-On/Off Control
GND
ONLY
N
FLAG
OUT
REV
IN
value. The
exceeds
OUT