No Preview Available !
• On-Chip Temperature Transducer
• Temperature Comparator Gives
Threshold Temperature Alarm
• Power Reference Permits Airflow
• Precision 2.5V Power Reference
Permits Airflow Diagnostics
• Transducer Output is Easily Scaled
for Increased Sensitivity
• Low 2.5mA Quiescent Current
The UC1730 family of integrated circuit devices are designed to be used in
a number of thermal monitoring applications. Each IC combines a tempera-
ture transducer, precision reference, and temperature comparator allowing
the device to respond with a logic output if temperatures exceed a user pro-
grammed level. The reference on these devices is capable of supplying in
excess of 250mA of output current − by setting a level of power dissipation
the rise in die temperature will vary with airflow past the package, allowing
the IC to respond to airflow conditions
These devices come in an 8-Pin DIP, plastic or ceramic, a 5-Pin TO-220 or a
PLCC-20 version. In the 8-Pin version, a PTAT (proportional to absolute
temperature) output reports die temperature directly. This output is config-
ured such that its output level can be easily scaled up with two external gain
resistors. A second PTAT source is internally referenced to the temperature
comparator. The other input to this comparator can then be externally pro-
grammed to set a temperature threshold. When this temperature threshold
is exceeded an alarm delay output is activated. Following the activation of
the delay output, a separate open collector output is turned on. The delay
pin can be programmed with an external RC to provide a time separation
between activation of the delay pin and the alarm pin, permitting shutdown
diagnostics in applications where the open collector outputs of multiple parts
are wire OR’ed together.
The 5-Pin version in the TO-220 package is well suited for monitoring
heatsink temperatures. Enhanced airflow sensitivities can be obtained with
this package by mounting the device to a small heatsink in the airstream.
This version of the device does not include the PTAT output or the open col-
lector alarm output.
Pin numbers shown for 8-Pin DIP, ( ) number for 5-Pin TO-220.
No Preview Available !
www.DataSheet.jp | 2019 | メール | 最新 | Sitemap