2.3 V memory module temperature sensor
Features
■ STTS3000 is a 2.3 V memory module
temperature sensor forward compatible with
JEDEC standard TS3000 and backward
compatible with STTS424
■ Operating temperature range:
– –40 °C to +125 °C
■ Single supply voltage: 2.3 V to 3.6 V
■ Temperature sensor resolution:
programmable (9-12 bits)
0.25 °C (typ)/LSB - (10-bit) default
■ Temperature sensor accuracy (max):
– ± 1 °C from +75 °C to +95 °C
– ± 2 °C from +40 °C to +125 °C
– ± 3 °C from –40 °C to +125 °C
■ ADC conversion time: 125 ms (max) at default
resolution (10-bit)
■ Typical operating supply current: 160 µA
■ Temperature hysteresis selectable set points
from: 0, 1.5, 3, 6.0 °C
■ Two-wire SMBus/I
interface
■ Supports up to 400 kHz transfer rate
■ Does not initiate clock stretching
■ Supports SMBus timeout 25 ms - 35 ms
■ Spike suppression filters on the two-wire bus
inputs
■ Voltage hysteresis per I
wire bus inputs
2
C - compatible serial
2
C specs on the two-
STTS3000
Data brief
TDFN8 (DN)
2 mm x 3 mm (max height 0.80 mm)
■ 2 mm x 3 mm TDFN8, height: 0.80 mm (max)
RoHS compliant, halogen-free
■
(a)
(a)
a. Compliant to JEDEC MO-229, WCED-3
April 2010 Doc ID 17407 Rev 1 1/8
For further information contact your local STMicroelectronics sales office.
www.st.com
1
Description STTS3000
1 Description
The STTS3000 is targeted for DIMM modules in mobile personal computing platforms
(laptops), servers and other industrial applications. The thermal sensor (TS) in the
STTS3000 is compliant with the JEDEC specification TS3000 which defines memory
module thermal sensors requirements for mobile platforms.
The TS provides space as well as cost savings for mobile and server platform dual inline
memory modules (DIMM) manufacturers, as it is packaged in the compact 2 mm x 3 mm
8-lead TDFN package with a thinner maximum height of 0.80 mm. The DN package is
compliant to JEDEC MO-229, variation WCED-3.
The digital temperature sensor has a programmable 9-12 bit analog-to-digital converter
(ADC) which monitors and digitizes the temperature to a resolution of up to 0.0625 °C. The
default resolution is 0.25 °C/LSB (10-bit). The typical accuracies over these temperature
ranges are:
● ±2 °C over the full temperature measurement range of –40 °C to 125 °C
● ±1 °C in the +40 °C to +125 °C active temperature range, and
● ±0.5 °C in the +75 °C to +95 °C monitor temperature range
The temperature sensor in the STTS3000 is specified for operating at supply voltages from
2.3 V to 3.6 V. Operating at 3.3 V, the typical supply current is 160 µA (includes SMBus
communication current).
The on-board sigma delta ADC converts the measured temperature to a digital value that is
calibrated in °C. For Fahrenheit applications, a lookup table or conversion routine is
required. The STTS3000 is factory-calibrated and requires no external components to
measure temperature.
The digital temperature sensor has user-programmable registers that provide the
capabilities for DIMM temperature-sensing applications. The open drain event output pin is
active when the monitoring temperature exceeds a programmable limit, or it falls above or
below an alarm window. The user has the option to set the event output as a critical
temperature output. This pin can be configured to operate in either a comparator mode for
thermostat operation or in interrupt mode.
2/8 Doc ID 17407 Rev 1
STTS3000 Description
Figure 1. Logic diagram
V
DD
SDA
(1)
EVENT
(1)
SCL
STTS3000
V
SS
1. SDA and EVENT are open drain.
Table 1. Signal names
A
A
A
2
1
0
Pin Symbol Description Type
1 A0 Serial bus address selection pin. Can be tied to V
2 A1 Serial bus address selection pin. Can be tied to V
3 A2 Serial bus address selection pin. Can be tied to V
4V
SS
5SDA
Supply ground
(1)
Serial data Input/output
or VDD. Input
SS
or VDD. Input
SS
or VDD. Input
SS
6 SCL Serial clock Input
DD
(1)
Event output pin. Open drain and active-low. Output
Supply power (2.3 V to 3.6 V)
7 EVENT
8V
1. SDA and EVENT are open drain.
AI12261
Figure 2. TDFN8 connections (top view)
A0
A1
A2
GND
1. SDA and EVENT are open drain.
Doc ID 17407 Rev 1 3/8
1
2
3
4
V
8
7
6
5
DD
EVENT
SCL
(1)
SDA
(1)
AI12262