TelCom Semiconductor Inc TCN75-5.0MOA, TCN75-3.3MUA, TCN75-3.3MOA, TCN75-3.3MPA, TCN75-5.0MPA Datasheet
...
2-WIRE SERIAL TEMPERATURE
PRELIMINARY INFORMATION
SENSOR AND THERMAL MONIT OR
TCN75
TCN75
2-WIRE SERIAL TEMPERATURE SENSOR AND THERMAL MONITOR
FEATURES
■
Solid State Temperature Sensing; 2°C Accuracy (Typ.)
■ Operates from – 55°C to +125°C
■ Operating Range..................................... 2.7V - 5.5V
■ Programmable Trip Point and Hysteresis with
Power-up Defaults
■ Standard 2-Wire Serial Interface
■ Thermal Event Alarm Output Functions as
Interrupt or Comparator / Thermostat Output
■ Up to 8 TCN75's May Share the Same Bus
■ Shutdown Mode for Low Standby Power
Consumption
■ Low Power......................... 250µA (Typ.) Operating
1µA (Typ.) Shutdown Mode
■ 8-Pin Plastic DIP, SOIC, and MSOP Packaging
TYPICAL APPLICATIONS
■ Thermal Protection for High Performance CPU's
■ Solid-State Thermometer
■ Fire/Heat Alarms
■ Thermal Management in Electronic Systems:
Computers
Telecom Racks
Power Supplies / UPS* / Amplifiers
■ Copiers / Office Electronics
■ Consumer Electronics
■ Process Control
GENERAL DESCRIPTION
The TCN75 is a serially programmable temperature
sensor that notifies the host controller when ambient tem-
perature exceeds a user-programmed setpoint. Hysteresis
is also programmable. The INT/CMPTR output is programmable as either a simple comparator for thermostat operation or as a temperature event interrupt. Communication
with the TCN75 is accomplished via a two-wire bus that is
compatible with industry standard protocols. This permits
reading the current temperature, programming the setpoint
and hysteresis, and configuring the device.
The TCN75 powers up in Comparator Mode with a
default setpoint of 80°C with 5°C hysteresis. Defaults allow
independent operation as a stand-alone thermostat. A shutdown command may be sent via the 2-wire bus to activate
the low-power standby mode. Address selection inputs
allow up to eight TCN75's to share the same 2-wire bus for
multi-zone monitoring.
All registers can be read by the host and the INT/
CMPTR output's polarity is user programmable. Both polled
and interrupt driven systems are easily accommodated.
Small physical size, low installed cost, and ease of use make
the TCN75 an ideal choice for implementing sophisticated
system management schemes.
ORDERING INFORMATION
Supply Junction
Part No. Voltage (V) Package Temp. Range
TCN75-3.3MOA 3.3 8-Pin SOIC – 55°C to +125°C
TCN75-5.0MOA 5.0 8-Pin SOIC – 55°C to +125°C
T
CN75-3.3MPA 3.3 8-Pin PDIP – 55°C to +125°C
TCN75-5.0MPA 5.0 8-Pin PDIP – 55°C to +125°C
TCN75-3.3MUA 3.3 8-MSOP – 55°C to +125°C
TCN75-5.0MUA 5.0 8-MSOP – 55°C to +125°C
FUNCTIONAL BLOCK DIAGRAM
9 Bit
∆Σ
A/D
Temp
DD
SDA
SCL
Sensor
A
0
A
1
A
2
V
TCN75-04 6/16/97
Converter
Register Set
Configuration
Temperature
Two Wire
Serial Port
Interface
TelCom Semiconductor reserves the right to make changes in the circuitry and specifications of its devices.
T
T
Control
SET
HYST
Logic
TCN75
INT/CMPTR
PIN CONFIGURATIONS
8-Pin Plastic DIP
1
SDA V
2
SCL
INT/CMPTR A1
INT/CMPTR
1
GND
SDA
SCL
GND
3
TCN75MPA
4
8-Pin SOIC
1
2
TCN75MOA
3
4
8
7
6
5
8
7
6
5
DD
A0
A2
V
DD
A0
A1
A2
SDA
SCL
INT/CMPTR
GND
8-Pin MSOP
1
2
TCN75MUA
3
4
V
8
DD
7
A0
6
A1
5
A2
PRELIMINARY INFORMATION
TCN75
2-WIRE SERIAL TEMPERATURE
SENSOR AND THERMAL MONIT OR
ABSOLUTE MAXIMUM RATINGS*
Supply Voltage (VDD) .................................................6.0V
ESD Susceptibility (Note 2)..................................... (TBD)
Voltage on Any Pin............. (GND – 0.3V) to (VDD + 0.3V)
Operating Temperature Range (TJ) ......– 55°C to +125°C
Storage Temperature Range (T
ELECTRICAL CHARACTERISTICS: V
) .....– 65°C to +150°C
STG
DD
= 2.7V – 5.5V, – 55°C ≤ (TA = TJ) ≤ 125°C, unless otherwise noted.
Lead Temperature (Soldering, 10 sec) ................. +300°C
Thermal Resistance (Junction to Ambient)
8-Pin DIP...................................................... 110°C/W
8-Pin SOIC .................................................. 170°C/W
8-Pin MSOP................................................ 250°C//W
*This is a stress rating only and functional operation of this device at these
or any other conditions above those indicated in the operations sections of
this specification is not implied.
Symbol Parameter Test Conditions Min Typ Max Unit
Power Supply
V
I
I
DD
DD
DD1
Power Supply Voltage 2.7 — 5.5 V
Operating Current
Serial Port Inactive (T
= TJ = 25°C)
A
— 0.250 — mA
Serial Port Active — — 1.0
Standby Supply Current Shutdown Mode, Serial Port Inactive — 1 — µA
(TA = TJ = 25°C)
INT/CMPTR Output
I
OL
t
TRIP
V
OL
Sink Current: INT/CMPTR, SDA Note 1 — 1 4 mA
Outputs
INT/CMPTR Response Time User Programmable 1 — 6 t
CONV
Output Low Voltage IOL = 4.0mA — — 0.8 V
Temp-to-Bits Converter
∆T Temperature Accuracy (Note 2) – 55°C ≤ TA ≤ +125°C—±3—°C
V
= 3.3V : TCN75-3.3MOA,
DD
TCN75-3.3MPA, TCN75-3.3MUA
= 5.0V: TCN75-5.0MOA,
V
DD
TCN75-5.0MPA, TCN75-5.0 MUA
25°C ≤ TA ≤ 100°C—±0.5 ±2 °C
t
CONV
T
SET(PU)
T
HYST(PU)
Conversion Time — 100 — msec
TEMP Default Value Power Up — 80 — °C
T
Default Value Power Up — 75 — °C
HYST
2-Wire Serial Bus Interface
V
IH
V
IL
V
OL
C
IN
I
LEAK
I
OL(SDA)
Logic Input High VDD x 0.7 — — V
Logic Input Low — — VDD x 0.3 V
Logic Output Low IOL = 3mA — — 0.4 V
Input Capacitance SDA, SCL — 15 — pF
I/O Leakage
(TA = TJ = 25°C)
— ±100 — pA
SDA Output Low Current — — 6 mA
SERIAL PORT TIMING: 2.7V ≤ V
≤ 5.5V; – 55°C ≤ (TA = TJ ) ≤ 125°C, CL = 80pf, unless otherwise noted.
DD
Symbol Parameter Test Conditions Min Typ Max Unit
f
SC
t
LOW
t
HIGH
t
R
t
F
t
SU(START)
TCN75-04 6/16/97
Serial Port Frequency 0 100 400 kHz
Low Clock Period 1250 — — nsec
High Clock Period 1250 — — nsec
SCL and SDA Rise Time — — 250 nsec
SCL and SDA Fall Time — — 250 nsec
Start Condition Setup Time 1250 — — nsec
(for repeated Start Condition)
2
2-WIRE SERIAL TEMPERATURE
SENSOR AND THERMAL MONIT OR
PRELIMINARY INFORMATION
TCN75
SERIAL PORT TIMING (Cont.): 2.7V ≤ V
≤ 5.5V; – 55°C ≤ (TA = TJ ) ≤ 125°C, CL = 80pf, unless otherwise
DD
noted.
Symbol Parameter Test Conditions Min Typ Max Unit
t
H(START)
t
DSU
t
DH
t
SU(STOP)
t
IDLE
NOTES: 1. Output current should be minimized for best temperature accuracy. Power dissipation within the TCN75 will cause self-heating and
Start Condition Hold Time 1250 — — nsec
Data in Setup Time to SCL High 100 — — nsec
Data in Hold Time after SCL Low 0 — — nsec
Stop Condition Setup Time 1250 — — nsec
Bus Free Time Prior to New 1250 — — nsec
Transition
temperature drift. At maximum rated output current and saturation voltage, 4mA and 0.8V, respectively, the error amounts to 0.352°C for the
PDIP, and 0.544°C for the SOIC.
2. All part types of the TCN75 will operate properly over the wider power supply range of 2.7V to 5.5V. Each part type is tested and specified
for rated accuracy at its nominal supply voltage. As VDD varies from the nominal value, accuracy will degrade 1°C/V of VDD change.
3. Human body model, 100pF discharged through a 1.5k resistor, machine model, 200pF discharged directly into each pin.
PIN DESCRIPTION
Pin Number Symbol Description
1 SDA Bidirectional Serial Data.
2 SCL Serial Data Clock Input.
3 INT/CMPTR Interrupt or Comparator Output.
4 GND System Ground.
5A
6A
7A
8VDDPower Supply Input.
2
1
0
Address Select Pin (MSB).
Address Select Pin.
Address Select Pin (LSB).
DETAILED DESCRIPTION
A typical TCN75 hardware connection is shown in
Figure 1.
Serial Data (SDA)
Bidirectional. Serial data is transferred in both directions
using this pin.
Serial Clock (SCL)
Input. Clocks data into and out of the TCN75.
INT/CMPTR
Open Collector, Programmable Polarity. In Comparator
Mode, unconditionally driven active any time temperature
exceeds the value programmed into the T
CMPTR will become inactive when temperature subsequently falls below the T
Programmer's Model.
setting. (See
HYST
) In Interrupt Mode, INT/CMPTR is
also made active by TEMP exceeding T
ally reset to its inactive state by reading any register via the
2-wire bus. If and when temperature falls below T
CMPTR is again driven active. Reading any register will
clear the T
TCN75-04 6/16/97
interrupt. In Interrupt Mode, the INT/CMPTR
HYST
register. INT/
SET
Register Set and
; it is uncondition-
SET
HYST
, INT/
output is unconditionally reset upon entering Shutdown
Mode. If programmed as an active-low output, it can be
wire-ORed with any number of other open collector devices.
Most systems will require a pull-up resistor for this configuration.
Note that current sourced from the pull-up resistor
causes power dissipation and may cause internal heating of
the TCN75. To avoid affecting the accuracy of ambient
temperature readings, the pull-up resistor should be made
as large as possible. INT/CMPTR's output polarity may be
programmed by writing to the INT/CMPTR POLARITY bit in
the CONFIG register. The default is active low.
Address (A2, A1, A0)
Inputs. Sets the three least significant bits of the TCN75
8-bit address. A match between the TCN75's address and
the address specified in the serial bit stream must be made
to initiate communication with the TCN75. Many protocolcompatible devices with other addresses may share the
same 2-wire bus.
Slave Address
The four most significant bits of the Address Byte (A6,
A5, A4, A3) are fixed to 1001[B]. The states of A2, A1 and
3
Loading...