LTC1710CMS8#TR Linear Technology, LTC1710CMS8#TR Datasheet - Page 7

• Manufacturer Part Number: LTC1710CMS8#TR
• Description: IC SWITCH SMBUS DUAL HISD 8MSOP
• Manufacturer: Linear Technology
• Type: High Sider

Specifications of LTC1710CMS8#TR

• Input Type: 2-Wire SMBus
• Number Of Outputs: 2
• On-state Resistance: 400 mOhm
• Current - Output / Channel: 300mA
• Current - Peak Output: 1A
• Voltage - Supply: 2.7 V ~ 5.5 V
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 8-MSOP, Micro8™, 8-uMAX, 8-uSOP,
• Switch Type: High Side
• Power Switch Family: LTC1710
• Input Voltage: 2.7 to 5.5V
• Power Switch On Resistance: 550mOhm
• Mounting: Surface Mount
• Supply Current: 17uA
• Package Type: MSOP
• Operating Temperature (min): 0C
• Operating Temperature (max): 70C
• Operating Temperature Classification: Commercial
• Pin Count: 8
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

OPERATIO
Charge Pump
To fully enhance the internal N-channel power switches,
an internal charge pump is used to boost the gate drive to
a maximum of 6V above V
charge pump output voltage limit is to protect the internal
switches from excessive gate overdrive. A feedback net-
work is used to limit the charge pump output once it is 6V
above V
too fast, an internal current source is placed between the
output of the charge pump and the gate of the power
switch to control the ramp rate.
Since the charge pumps are driving just the gates of the
internal switches, only a small amount of current is
required. Therefore, all the charge pump capacitors are
integrated onboard. The drain of switch 1 is internally
connected to V
controlled through Pin 1. In other words, SMBus devices
using different power supply voltages can be simulta-
neously switched by the same LTC1710.
Power-On Reset and Undervoltage Lockout
The LTC1710 starts up with both gate drives low. An
internal power-on reset (POR) signal inhibits operation
TYPICAL APPLICATIONS
The LTC1710, when used with the LT
switch a regulated 3.3V/300mA supply to a load (Figure 3).
Also, with the help of the LT1304-5, the LTC1710 can be
Figure 3. Low Dropout Regulator Switching a 3.3V/300mA Supply
PROGRAMMABLE
FROM SMBus
CC
10 F
. To prevent the power switches from turning on
CC
5
6
3
CLK
DATA
, however, the drain of switch 0 is user
AD1
U
LTC1710
GND
V
5V
CC
8
SW0D
4
OUT1
OUT0
CC
. The reason for the maximum
7
1
2
Information furnished by Linear Technology Corporation is believed to be accurate and reliable.
However, no responsibility is assumed for its use. Linear Technology Corporation makes no represen-
tation that the interconnection of its circuits as described herein will not infringe on existing patent rights.
SWITCHED
3.3V
1 F
U
8
5
V
SHDN
IN
LT1521-3.3
®
1521-3.3, can
SENSE
V
OUT
1
2
1710 F03
3.3V
1.5 F
until about 300 s after V
lockout threshold (typically 2V). The circuit includes some
hysteresis and delay to avoid nuisance resets. Once opera-
tion begins, V
100 s to trigger another POR sequence.
Input Threshold
Anticipating the trend of lower and lower supply voltages,
the SMBus is specified with a V
While some SMBus parts may violate this stringent SMBus
specification by specifying a higher V
sponding higher input supply voltage, the LTC1710 meets
and maintains the constant SMBus input threshold speci-
fication throughout the entire supply voltage range of 2.7V
to 5.5V.
Thermal Shutdown
In the unlikely event that either power switch overheats, a
thermal shutdown circuit, which is placed closely to the
two switches, will activate and turn off the gate drives to
both switches. The thermal shutdown circuit has a thresh-
old of 120 C with a 15 C hysteresis.
used to make a boost switching regulator with output
disconnect and a low standby current of 22 A (Figure 5).
Figure 4. The LTC1710 Switching Two Different Voltage Loads
FROM SMBus
PROGRAMMABLE
CC
10 F
must drop below the threshold for at least
5
6
3
CC
CLK
DATA
AD1
V
5V
CC
LTC1710
8
GND
crosses the undervoltage
IH
SW0D
4
of 1.4V and a V
3.3V
OUT0
OUT1
1
IH
2
7
value for a corre-
LTC1710
LOAD
LOAD
10 F
3.3V
5V
1710 F04
IL
of 0.6V.
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