PHILIPS SE98PW

SE98
SO-DIMM SMBus/I2C-bus temperature sensor
Rev. 02 — 7 January 2008
Product data sheet
1. General description
The NXP Semiconductors SE98 measures temperature from −20 °C and +125 °C
communicating via the I2C-bus/SMBus. It is typically mounted on a Dual In-Line Memory
Module (DIMM) measuring the DRAM temperature in accordance with the new JEDEC
(JC-42.4) Mobile Platform Memory Module Thermal Sensor Component specification.
Placing the Temp Sensor (TS) on DIMM allows accurate monitoring of the DIMM module
temperature to better estimate the DRAM case temperature (Tcase) to prevent it from
exceeding the maximum operating temperature of 85 °C. The chip set throttles the
memory traffic based on the actual temperatures instead of the calculated worst-case
temperature or the ambient temperature using a temp sensor mounted on the
motherboard. There is up to a 30 % improvement in thin and light notebooks that are
using one or two 1G SO-DIMM modules, although other memory modules such as in
server applications will also see an increase in system performance. Future uses of the
TS will include more dynamic control over thermal throttling, the ability to use the Alarm
Window to create multiple temperature zones for dynamic throttling and to save processor
time by scaling the memory refresh rate.
The TS consists of an Analog-to-Digital Converter (ADC) that monitors and updates its
own temperature readings 8 times per second, converts the reading to a digital data, and
latches them into the data temperature registers. User-programmable registers, such as
Shutdown or Low-power modes and the specification of temperature event and critical
output boundaries, provide flexibility for DIMM temperature-sensing applications.
When the temperature changes beyond the specified boundary limits, the SE98 outputs
an EVENT signal. The user has the option of setting the EVENT output signal polarity as
either an active LOW or active HIGH comparator output for thermostat operation, or as a
temperature event interrupt output for microprocessor-based systems. The EVENT output
can even be configured as a critical temperature output.
The SE98 supports the industry-standard 2-wire I2C-bus/SMBus serial interface. The
SMBus TIMEOUT function is supported to prevent system lock-ups. Manufacturer and
Device ID registers provide the ability to confirm the identify of the device. Three address
pins allow up to eight devices to be controlled on a single bus. To maintain
interchangeability with the I2C-bus/SMBus interface the electrical specifications are
specified with the operating voltage of 3.0 V to 3.6 V.
DIMM applications normally use the C-grade accuracy SE98PW or SE98TK temp sensor.
For applications requiring the higher B-grade accuracy, the SE98PW/1 or SE98TK/1 is
available.
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
2. Features
2.1 General features
n
n
n
n
n
n
JEDEC (JC-42.4) SO-DIMM temperature sensor
Optimized for voltage range: 3.0 V to 3.6 V
Shutdown/Standby current: 8 µA (typ.) and 15 µA (max.)
2-wire interface: I2C-bus/SMBus compatible, 0 Hz to 400 kHz
SMBus ALERT and TIMEOUT (programmable)
Available packages: TSSOP8 and HVSON8
2.2 Temperature sensor features
n
n
n
n
n
Temperature-to-Digital converter
Operating current: 200 µA (typ.) and 250 µA (max.)
Programmable hysteresis threshold: 0 °C, 1.5 °C, 3 °C, 6 °C
Over/under/critical temperature EVENT output
B grade accuracy:
u ±0.5 °C/±1 °C (typ./max.) → +75 °C to +95 °C
u ±1 °C/±2 °C (typ./max.) → +40 °C to +125 °C
u ±2 °C/±3 °C (typ./max.) → −20 °C to +125 °C
n C grade accuracy:
u ±1 °C/±2 °C (typ./max.) → +75 °C to +95 °C
u ±2 °C/±3 °C (typ./max.) → +40 °C to +125 °C
u ±3 °C/±4 °C (typ./max.) → −20 °C to +125 °C
3. Applications
n
n
n
n
DDR2 and DDR3 memory modules
Laptops, personal computers and servers
Enterprise networking
Hard disk drives and other PC peripherals
4. Ordering information
Table 1.
Ordering information
Type number
Topside
mark
Package
Name
Description
Version
SE98PW
SE98
TSSOP8
plastic thin shrink small outline package; 8 leads;
body width 4.4 mm
SOT530-1
SE98TK
SE98
HVSON8
plastic thermal enhanced very thin small outline package;
no leads; 8 terminals; body 3 × 3 × 0.85 mm
SOT908-1
SE98_2
Product data sheet
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Rev. 02 — 7 January 2008
2 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
5. Block diagram
SE98
REGISTERS
A0
A1
A2
CRITICAL TEMPERATURE LIMIT
LOCK
PROTECT
BAND GAP
TEMPERATURE
SENSOR
VDD
UPPER TEMPERATURE LIMIT
LOWER TEMPERATURE LIMIT
11-BIT
∆Σ ADC
HYSTERESIS THRESHOLD
MANUFACTURER ID
TEMPERATURE
REGISTER
DEVICE ID
DEVICE CAPABILITY REGISTER
CONFIGURATION REGISTER
EVENT
CONTROL LOGIC
SCL
I2C-bus/SMBus
INTERFACE
SDA
VSS
EVENT OUTPUT COMPARATOR/INT MODE
EVENT OUTPUT POLARITY
POR
CIRCUIT
ENABLE/DISABLE EVENT OUTPUT
EVENT OUTPUT STATUS
SENSOR ENABLE/SHUTDOWN
002aab280
Fig 1. Block diagram of SE98
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
3 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
6. Pinning information
6.1 Pinning
terminal 1
index area
A0
1
A1
2
8
VDD
7
EVENT
SE98TK
A0
1
A1
2
A2
3
VSS
4
SE98PW
8
VDD
7
EVENT
6
SCL
5
SDA
A2
3
6
SCL
VSS
4
5
SDA
002aab804
Transparent top view
002aab806
Fig 2. Pin configuration for TSSOP8
Fig 3. Pin configuration for HVSON8
6.2 Pin description
Table 2.
Pin description
Symbol
Pin
Type
Description
A0[1]
1
I
I2C-bus/SMBus slave address bit 0
A1
2
I
I2C-bus/SMBus slave address bit 1
A2
3
I
I2C-bus/SMBus slave address bit 2
VSS
4
ground
device ground
SDA
5
I/O
SMBus/I2C-bus serial data input/output (open-drain).
Must have external pull-up resistor.
SCL
6
I
SMBus/I2C-bus serial clock input/output (open-drain).
Must have external pull-up resistor.
EVENT
7
O
Thermal alarm output for high/low and critical temperature
limit (open-drain). Must have external pull-up resistor.
VDD
8
power
device power supply (3.0 V to 3.6 V)
[1]
In general, application of 10 V on the A0 pin would not damage the pin, but NXP Semiconductors does not
guarantee the overvoltage for this pin.
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
4 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
7. Functional description
7.1 Serial bus interface
The SE98 uses the 2-wire serial bus (I2C-bus/SMBus) to communicate with a host
controller. The serial bus consists of a clock (SCL) and data (SDA) signals. The device
can operate on either the I2C-bus Standard/Fast mode or SMBus. The I2C-bus Standard
mode is defined to have bus speeds from 0 Hz to 100 kHz, I2C-bus Fast mode from 0 Hz
to 400 kHz, and the SMBus is from 10 kHz to 100 kHz. The host or bus master generates
the SCL signal, and the SE98 uses the SCL signal to receive or send data on the SDA
line. Data transfer is serial, bidirectional, and is one bit at a time with the Most Significant
Bit (MSB) transferred first, and a complete I2C-bus data is 1 byte. Since SCL and SDA are
open-drain, pull-up resistors must be installed on these pins.
7.2 Slave address
The SE98 uses a 4-bit fixed and 3-bit programmable (A0, A1 and A2) 7-bit slave address
that allows a total of eight devices to co-exist on the same bus. The input of each pin is
sampled at the start of each I2C-bus/SMBus access. The temperature sensor’s fixed
address is 0011.
slave address
R/W
MSB
0
LSB
0
1
1
fixed
A2
A1
A0
X
hardware
selectable
002aab304
Fig 4. Slave address
7.3 EVENT output
The EVENT pin is an open-drain output whose function can be programmed as an
interrupt, comparator, or critical alarm mode. When the device operates in Interrupt mode,
and the temperature reaches a critical temperature, the device switches to the comparator
mode automatically and asserts the EVENT pin. When the temperature drops below
critical temperature, the device reverts back to either interrupt or comparator mode, as
programmed in the Configuration register. The interrupt latch can be cleared by writing a
‘1’ to the ‘clear EVENT’ bit in the Configuration register or by performing the SMBus Alert
Response Address (ARA).
In comparator mode, the EVENT pin remains asserted until the temperature falls below
the value programmed in the Upper Boundary Alarm Trip register or rises above the value
programmed in the Lower Boundary Alarm Trip register, or until the range of these alarm
registers are reprogrammed and the temperature falls inside the alarm limits. Figure 5
depicts the EVENT output for all the three modes. All event thresholds use hysteresis as
programmed in the Configuration register.
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
5 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
temperature (°C)
critical
hysteresis
Upper Boundary Alarm
alarm window
Lower Boundary Alarm
software clears event
time
EVENT in Interrupt mode(1)
EVENT in Comparator mode(1)
software interrupt clear
EVENT in ‘Critical Temp only’ mode(1)
002aab233
(1) EVENT pin shown here is active LOW. It can be programmed to be active HIGH.
Fig 5. EVENT output for ‘Interrupt’, ‘Comparator’, and ‘Critical Temp only’ modes
7.3.1 Alarm window
The alarm window consists of two registers: an Upper Boundary Alarm Trip register (02h),
and a Lower Boundary Alarm Trip register (03h). The Upper Boundary Alarm Trip register
holds the upper temperature trip point, while the Lower Boundary Alarm Trip register holds
the lower temperature trip point. When the EVENT control is enabled, the EVENT output
will be triggered whenever entering or exiting the alarm window.
7.3.2 Critical trip
The device can be programmed in such a way that the EVENT output is triggered when
the temperature exceeds the critical trip point set by the Critical Alarm Trip register (04h).
When the temperature sensor reaches the critical temperature value, the device is
automatically placed in comparator mode; the EVENT output is only cleared when the
temperature falls below the critical temperature value and cannot be cleared through the
clear EVENT bit or SMBus Alert.
7.4 Conversion rate
The conversion time is the amount of time required for the ADC to complete a temperature
measurement for the local temperature sensor. The conversion rate is the inverse of the
conversion period which describes the number of cycles the temperature measurement
completes in one second—the faster the conversion rate, the faster the temperature
reading is updated. The SE98’s conversion rate is at least 8 Hz or 125 ms.
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
6 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
7.5 Power-up default condition
After power-on, the SE98 is initialized to the following default condition:
•
•
•
•
•
Starts monitoring local sensor
EVENT register is cleared—EVENT output is pulled HIGH by external pull-ups
EVENT hysteresis is defaulted to 0 °C
Command pointer is defaulted to ‘00h’
Critical Temp, Alarm Temperature Upper and Lower Boundary Trip register are
defaulted to 0 °C
• Capability register is defaulted to ‘0015h’
• Operational mode: comparator
• SMBus register is defaulted to ‘00h’
7.6 Device initialization
SE98 temperature sensors have programmable registers, which, upon power-up, default
to zero. The open-drain EVENT output is default to being disabled, comparator mode and
active LOW. The alarm trigger registers default to being unprotected. The configuration
registers, upper and lower alarm boundary registers and critical temperature window are
defaulted to zero and need to be programmed to the desired values. SMBus TIMEOUT
feature defaults to being enabled and can be programmed to disable. These registers are
required to be initialized before the device can properly function. Except for the SPD,
which does not have any programmable registers, and does not need to be initialized.
Table 3 shows the default values and the example value to be programmed to these
registers.
Table 3.
Registers to be initialized
Register
Default value
Example value
Description
01h
0000h
0209h
Configuration register
•
•
•
hysteresis = 1.5 °C
EVENT output = Interrupt mode
EVENT output is enabled
02h
0000h
0550h
Upper Boundary Alarm Trip register = 85 °C
03h
0000h
1F40h
Lower Boundary Alarm Trip register = −20 °C
04h
0000h
05F0h
Critical Alarm Trip register = 95 °C
22h
0000h
0000h
SMBus register = no change
7.7 SMBus Time-out
The SE98 supports the SMBus time-out feature. If the host holds SCL LOW between
25 ms and 35 ms, the SE98 would reset its internal state machine to the bus idle state to
prevent the system bus hang-up. This feature is turned on by default. The SMBus time-out
is disabled by writing a logic 1 to bit 7 of register 22h.
Remark: When SMBus time-out is enabled, the I2C-bus minimum bus speed is limited by
the SMBus time-out timer, and goes down to only 10 kHz.
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
7 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
7.8 SMBus Alert
The SE98 supports SMBus Alert when it is programmed for the Interrupt mode and when
the EVENT polarity bit is set to logic 0. The EVENT pin can be ANDed with other EVENT
or ALERT signals from other slave devices to signal their intention to communicate with
the host controller. When the host detects EVENT or ALERT signal LOW, it issues an
Alert Response Address (ARA) to which a slave device would respond with its address.
When there are multiple slave devices generating an Alert the SE98 performs bus
arbitration. If it wins the bus, it responds to the ARA and then clears the EVENT pin.
Remark: Either in comparator mode or when the SE98 crosses the critical temperature,
the host must also read the EVENT status bit and provide remedy to the situation by
bringing the temperature to within the alarm window or below the critical temperature if
that bit is set. Otherwise, the EVENT pin will not get de-asserted.
read
START bit
S
host detects
SMBus ALERT
0
acknowledge
not acknowledge
Alert Response Address
0
0
1
1
0
STOP bit
device address
0
1
master sends a START bit,
ARA and a read command
0
0
0
1
1
A2
A1
Slave acknowledges and
sends its slave address.
The last bit of slave address
is hard coded '0'.
A0
0
1
P
host NACK and
sends a STOP bit
002aab330
Fig 6. How SE98 responds to SMBus Alert
7.9 SMBus/I2C-bus interface
The data registers in this device are selected by the Pointer register. At power-up, the
Pointer register is set to ‘00’, the location for the Capability register. The Pointer register
latches the last location it was set to. Each data register falls into one of three types of
user accessibility:
• Read only
• Write only
• Write/Read same address.
A ‘write’ to this device will always include the address byte and the pointer byte. A write to
any register other than the Pointer register requires two data bytes.
Reading this device can take place either of two ways:
• If the location latched in the Pointer register is correct (most of the time it is expected
that the Pointer register will point to one of the Temperature register (as it will be the
data most frequently read), then the read can simply consist of an address byte,
followed by retrieving the two data bytes.
• If the Pointer register needs to be set, then an address byte, pointer byte,
repeat START, and another address byte will accomplish a read.
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
8 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
The data byte has the most significant bit first. At the end of a read, this device can accept
either Acknowledge (ACK) or No Acknowledge (NACK) from the Master (No Acknowledge
is typically used as a signal for the slave that the Master has read its last byte). It takes this
device 125 ms to measure the temperature. Refer to the timing diagrams in Figure 7,
Figure 8, Figure 9 and Figure 10 on how to program the device.
1
2
3
4
5
6
7
A6
A5
A4
A3
A2
A1
A0
8
9
W
A
1
2
3
4
5
6
7
8
D7
D6
D5
D4
D3
D2
D1
D0
9
SCL
SDA
S
START
A
ACK
by device
device address and write
P
ACK
STOP
by device
register address
002aab308
A = ACK = Acknowledge bit. W = Write bit = 0. R = Read bit = 1.
Fig 7. SMBus/I2C-bus write to the Pointer register
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
(cont.)
SCL
A6
SDA
A5
A4
A3
A2
A1
D7
A0
S
W
START
by host
1
2
3
4
5
6
7
D15
D14
D13
D12
D11
D10
D9
D5
D4
D3
D2
D1
(cont.)
D0
A
ACK
by device
8
9
1
device address and write
D6
A
write register address
2
3
4
5
6
7
D6
D5
D4
D3
D2
D1
ACK
by device
8
9
SCL
SDA
D7
D8
A
by host
most significant byte data
ACK
by device
D0
A
least significant byte data
P
ACK
STOP
by device by host
002aab412
A = ACK = Acknowledge bit. W = Write bit = 0. R = Read bit = 1.
Fig 8. SMBus/I2C-bus write to the Pointer register followed by a write data word
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
9 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
1
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
(cont.)
SCL
A6
SDA
A5
A4
A3
A2
A1
D7
A0
S
W
START
by host
2
3
4
5
D5
6
7
8
D4
D3
D2
D1
(cont.)
D0
A
ACK
by device
device address and write
1
D6
A
ACK
by device
read register address
9
(cont.)
SCL
A6
SDA
A5
A4
A3
A2
A1
repeated
START
by host
(cont.)
A0
SR
R
device address and read
A
ACK
by device
1
2
3
4
5
6
7
8
D15
D14
D13
D12
D11
D10
D9
D8
9
1
2
3
4
5
6
7
8
D7
D6
D5
D4
D3
D2
D1
D0
9
SCL
SDA
A
NA
ACK
by host
returned most significant byte data
P
NACK STOP
by host by host
returned least significant byte data
002aab413
A = ACK = Acknowledge bit. NA = Not Acknowledge bit. W = Write bit = 0. R = Read bit = 1.
Fig 9. SMBus/I2C-bus write to Pointer register followed by a repeat START and an immediate data word read
1
2
3
4
5
6
7
8
9
(cont.)
SCL
A6
SDA
A5
A4
A3
A2
A1
(cont.)
A0
S
R
START
by host
device address and read
A
ACK
by device
1
2
3
4
5
6
7
8
D15
D14
D13
D12
D11
D10
D9
D8
9
1
2
3
4
5
6
7
8
D7
D6
D5
D4
D3
D2
D1
D0
9
SCL
SDA
A
returned most significant byte data
ACK
by host
NA
returned least significant byte data
P
NACK STOP
by host
002aab414
A = ACK = Acknowledge bit. NA = Not Acknowledge bit. W = Write bit = 0. R = Read bit = 1.
Fig 10. SMBus/I2C-bus word read from register with a pre-set pointer
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
10 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
8. Register descriptions
8.1 Register overview
This section describes all the registers used in the SE98. The registers are used for
latching the temperature reading, storing the low and high temperature limits, configuring,
the hysteresis threshold and the ADC, as well as reporting status. The device uses the
Pointer register to access these registers. Read registers, as the name implies, are used
for read only, and the write registers are for write only. Any attempt to read from a
write-only register will result in reading zeroes. Writing to a read-only register will have no
effect on the read even though the write command is acknowledged. The Pointer register
is an 8-bit register. All other registers are 16-bit.
Table 4.
Register summary
Address
POR state
Register name
n/a
n/a
Pointer register
00h
0015h/0017h
Capability register (B-grade = 0017h, C-grade = 0015h)
01h
0000h
Configuration register
02h
0000h
Upper Boundary Alarm Trip register
03h
0000h
Lower Boundary Alarm Trip register
04h
0000h
Critical Alarm Trip register
05h
n/a
Temperature register
06h
1131h
Manufacturer ID register
07h
A101h
Device ID/Revision register
08h to 21h
0000h
reserved registers
22h
0000h
SMBus register
23h to FFh
0000h
reserved registers
A write to reserved registers my cause unexpected results which may result in requiring a
reset by removing and re-applying its power.
SE98_2
Product data sheet
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Rev. 02 — 7 January 2008
11 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
8.2 Capability register (00h, 16-bit read-only)
Table 5.
Capability register (address 00h) bit allocation
Bit
15
14
13
12
Symbol
11
10
9
8
RFU[10:3]
Reset
0
0
0
0
0
0
0
0
Access
R
R
R
R
R
R
R
R
Bit
7
6
5
4
3
2
1
0
WRNG
HACC
BCAP
Symbol
RFU[2:0]
TRES[1:0]
Reset
0
0
0
1
0
1
0
1
Access
R
R
R
R
R
R
R
R
Table 6.
Capability register (address 00h) bit description
Bit
Symbol
Description
15:5
RFU
Reserved for future use. Must be zero.
4:3
TRES
Temperature resolution.
10 — 0.125 °C LSB
2
WRNG
Wider range.
1 — can read temperatures below 0 °C and set sign bit accordingly
1
HACC
Higher accuracy bit set during manufacture.
0 — Accuracy ±2 °C over the active range and ±3 °C over the
monitor range (C-grade)
1 — High accuracy ±1 °C over the active range and ±2 °C over the
monitor range (B-grade)
0
BCAP
Basic capability.
1 — Has Alarm and Critical Trips capability.
SE98_2
Product data sheet
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Rev. 02 — 7 January 2008
12 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
8.3 Configuration register (01h, 16-bit read/write)
Table 7.
Configuration register (address 01h) bit allocation
Bit
15
14
13
Symbol
12
11
10
RFU
9
HEN[1:0]
8
SHMD
Default
0
0
0
0
0
0
0
0
Access
R
R
R
R
R
R/W
R/W
R/W
Bit
7
6
5
4
3
2
1
0
Symbol
CTLB
AWLB
CEVNT
ESTAT
EOCTL
CVO
EP
EMD
Default
0
0
0
0
0
0
0
0
Access
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Table 8.
Configuration register (address 01h) bit description
Bit
Symbol
Description
15:11
RFU
reserved for future use; must be ‘0’.
10:9
HEN
Hysteresis Enable
00 — Disable hysteresis (default)
01 — Enable hysteresis at 1.5 °C
10 — Enable hysteresis at 3 °C
11 — Enable hysteresis at 6 °C
When enabled, hysteresis is applied to temperature movement around
trigger points. For example, consider the behavior of the ‘Above Alarm
Window’ bit (bit 14 of the Temperature register) when the hysteresis is set
to 3 °C. As the temperature rises, bit 14 will be set to 1 (temperature is
above the alarm window) when the Temperature register contains a value
that is greater than the value in the Alarm Temperature Upper Boundary
register. If the temperature decreases, bit 14 will remain set until the
measured temperature is less than or equal to the value in the Alarm
Temperature Upper Boundary register minus 3 °C. (Refer to Figure 5 and
Table 9).
Similarly, the ‘Below Alarm Window’ bit (bit 13 of the Temperature register)
will be set to 0 (temperature is equal to or above the Alarm Window Lower
Boundary Trip register) when the value in the Temperature register is
equal to or greater than the value in the Alarm Temperature Lower
Boundary register. As the temperature decreases, bit 13 will be set to 1
when the value in the Temperature register is equal to or less than the
value in the Alarm Temperature Lower Boundary register minus 3 °C. Note
that hysteresis is also applied to EVENT pin functionality.
When either of the lock bits is set, these bits cannot be altered.
8
SHMD
Shutdown Mode.
0 — Enabled Temperature Sensor (default)
1 — Disabled Temperature Sensor
When shut down, the thermal sensor diode and Analog-to-Digital
Converter (ADC) are disabled to save power, no events will be generated.
When either of the lock bits is set, this bit cannot be set until unlocked.
However, it can be cleared at any time.
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
13 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
Table 8.
Configuration register (address 01h) bit description …continued
Bit
Symbol
Description
7
CTLB
Critical Trip Lock bit.
0 — Critical Alarm Trip register is not locked and can be altered
(default).
1 — Critical Alarm Trip register settings cannot be altered.
This bit is initially cleared. When set, this bit will return a 1, and remains
locked until cleared by internal Power-on reset. This bit can be written with
a single write and do not require double writes.
6
AWLB
Alarm Window Lock bit.
0 — Upper and Lower Alarm Trip registers are not locked and can be
altered (default).
1 — Upper and Lower Alarm Trip registers setting cannot be altered.
This bit is initially cleared. When set, this bit will return a 1 and remains
locked until cleared by internal power-on reset. This bit can be written with
a single write and does not require double writes.
5
CEVNT
Clear EVENT (write only).
0 — No effect (default).
1 — Clears active EVENT in Interrupt mode. Writing to this register has
no effect in Comparator mode.
When read, this register always returns zero.
4
ESTAT
EVENT Status (read only).
0 — EVENT output condition is not being asserted by this device
(default).
1 — EVENT output pin is being asserted by this device due to Alarm
Window or Critical Trip condition.
The actual event causing the event can be determined from the Read
Temperature register. Interrupt Events can be cleared by writing to the
‘clear EVENT’ bit. Writing to this bit will have no effect.
3
EOCTL
EVENT Output Control.
0 — EVENT output disabled (default).
1 — EVENT output enabled.
When either of the lock bits is set, this bit cannot be altered until unlocked.
2
CVO
Critical Event Only.
0 — EVENT output on Alarm or Critical temperature event (default)
1 — EVENT only if temperature is above the value in the critical
temperature register
When the alarm window lock bit is set, this bit cannot be altered until
unlocked.
1
EP
EVENT Polarity.
0 — active LOW (default).
1 — active HIGH. When either of the alarm or critical lock bits is set, this
bit cannot be altered until unlocked.
0
EMD
EVENT Mode.
0 — comparator output mode (default)
1 — interrupt mode
When either of the alarm or critical lock bits is set, this bit cannot be
altered until unlocked.
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
14 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
Table 9.
Action
Hysteresis Enable
Below Alarm Window Bit (bit 13)
Above Alarm Window Bit (bit 14)
Temperature
slope
Threshold
temperature
Temperature
slope
Temperature
sets
falling
Tth(low) − Hysteresis
rising
Tth(high)
clears
rising
Tth(low)
falling
Tth(high) − Hysteresis
current temperature
temperature
critical alarm
threshold
hysteresis
upper alarm
threshold
hysteresis
lower alarm
threshold
hysteresis
time
Above Critical Trip
(register 05h;
bit 15 = ACT bit)
clear
set
clear
Above Alarm Window
(register 05h;
bit 14 = AAW bit)
clear
set
clear
Below Alarm Window
(register 05h;
bit 13 = BAW bit)
set
clear
002aac799
Fig 11. Hysteresis: how it works
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
15 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
8.4 Temperature format
The 16-bit value used in the following Trip Point Set and Temperature Read-Back registers
is 2’s complement with the Least Significant Bit (LSB) equal to 0.0625 °C. For example:
• A value of 019Ch will represent 25.75 °C
• A value of 07C0h will represent 124 °C
• A value of 1E64h will represent −25.75 °C.
The resolution is 0.125 °C. The unused LSB (bit 0) is set to ‘0’. Bit 11 will have a resolution
of 128 °C.
The upper 3 bits of the temperature register indicate Trip Status based on the current
temperature, and are not affected by the status of the Event Output.
8.5 Temperature Trip Point registers
8.5.1 Upper Boundary Alarm Trip register (16-bit read/write)
The value is the upper threshold temperature value for Alarm mode. The data format is
2’s complement with bit 2 = 0.25 °C. ‘RFU’ bits will always report zero. Interrupts will
respond to the presently programmed boundary values. If boundary values are being
altered in-system, it is advised to turn off interrupts until a known state can be obtained to
avoid superfluous interrupt activity.
Table 10.
Bit
Upper Boundary Alarm Trip register bit allocation
15
Symbol
14
13
12
RFU
10
9
8
UBT[9:6]
Reset
0
0
0
0
0
0
0
0
Access
R
R
R
R/W
R/W
R/W
R/W
R/W
Bit
7
6
5
4
3
2
1
Symbol
Reset
Access
UBT[5:0]
0
RFU
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R
R
Table 11.
Upper Boundary Alarm Trip register bit description
Bit
Symbol
Description
15:13
RFU
reserved; always 0
12
SIGN
Sign (MSB)
11:2
UBT
Upper Boundary Alarm Trip Temperature (LSB = 0.25 °C)
1:0
RFU
reserved; always 0
SE98_2
Product data sheet
11
SIGN
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
16 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
8.5.2 Lower Boundary Alarm Trip register (16-bit read/write)
The value is the lower threshold temperature value for Alarm mode. The data format is
2’s complement with bit 2 = 0.25 °C. RFU bits will always report zero. Interrupts will
respond to the presently programmed boundary values. If boundary values are being
altered in-system, it is advised to turn off interrupts until a known state can be obtained to
avoid superfluous interrupt activity.
Table 12.
Lower Boundary Alarm Trip register bit allocation
Bit
15
Symbol
14
13
12
RFU
11
10
SIGN
9
8
LBT[9:6]
Reset
0
0
0
0
0
0
0
0
Access
R
R
R
R/W
R/W
R/W
R/W
R/W
Bit
7
6
5
4
3
2
1
0
Symbol
LBT[5:0]
Reset
Access
RFU
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R
R
Table 13.
Lower Boundary Alarm Trip register bit description
Bit
Symbol
Description
15:13
RFU
reserved; always 0
12
SIGN
Sign (MSB)
11:2
LBT
Lower Boundary Alarm Trip Temperature (LSB = 0.25 °C)
1:0
RFU
reserved; always 0
8.5.3 Critical Alarm Trip register (16-bit read/write)
The value is the critical temperature. The data format is 2’s complement with
bit 2 = 0.25 °C. RFU bits will always report zero.
Table 14.
Lower Boundary Alarm Trip register bit allocation
Bit
15
Symbol
14
13
12
RFU
10
9
8
CT[9:6]
Reset
0
0
0
0
0
0
0
0
Access
R
R
R
R/W
R/W
R/W
R/W
R/W
Bit
7
6
5
4
3
2
1
Symbol
CT[5:0]
Reset
Access
0
RFU
0
0
0
0
0
0
0
0
R/W
R/W
R/W
R/W
R/W
R/W
R
R
Table 15.
Critical Alarm Trip register bit description
Bit
Symbol
Description
15:13
RFU
reserved; always 0
12
SIGN
Sign (MSB)
11:2
CT
Critical Alarm Trip Temperature (LSB = 0.25 °C)
1:0
RFU
reserved; always 0
SE98_2
Product data sheet
11
SIGN
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
17 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
8.6 Temperature register (16-bit read-only)
Table 16.
Bit
Temperature register bit allocation
15
14
13
12
ACT
AAW
BAW
SIGN
Reset
0
0
0
0
0
0
0
0
Access
R
R
R
R
R
R
R
R
Bit
7
6
5
4
3
2
1
0
Symbol
Symbol
11
10
9
8
TEMP[10:7]
TEMP[6:0]
RFU
Reset
0
0
0
0
0
0
0
0
Access
R
R
R
R
R
R
R
R
Table 17.
Temperature register bit description
Bit
Symbol
Description
15
ACT
Above Critical Trip.
0 — temperature is below the Critical Alarm Trip register setting
1 — temperature is equal to or above the Critical Alarm Trip register
setting
14
AAW
Above Alarm Window.
0 — temperature is equal to or below the Upper Boundary Alarm Trip
register
1 — temperature is above the Alarm window
13
BAW
Below Alarm Window.
0 — temperature is equal to or above the Lower Boundary Alarm Trip
register
1 — temperature is below the Alarm window
12
SIGN
Sign bit.
0 — positive temperature value
1 — negative temperature value
11:1
TEMP
Temperature Value (2’s complement). (LSB = 0.125 °C)
0
RFU
reserved; always 0
8.7 Manufacturer’s ID register (16-bit read-only)
The manufacture’s ID matches that assigned to NXP Semiconductors PCI SIG (1131h),
and is intended for use to identify the manufacturer of the device.
Table 18.
Bit
Manufacturer’s ID register bit allocation
15
14
13
10
9
8
Reset
0
0
0
1
0
0
0
1
Access
R
R
R
R
R
R
R
R
Bit
7
6
5
4
3
2
1
0
Reset
0
0
1
1
0
0
0
1
Access
R
R
R
R
R
R
R
R
Symbol
12
Manufacturer ID
Symbol
(continued)
SE98_2
Product data sheet
11
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
18 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
8.8 Device ID register
The device ID and device revision are A1h and 00h, respectively.
Table 19.
Bit
Device ID register bit allocation
15
14
13
12
10
9
8
Reset
1
0
1
0
0
0
0
1
Access
R
R
R
R
R
R
R
R
Bit
7
6
5
4
3
2
1
0
Reset
0
0
0
0
0
0
0
1
Access
R
R
R
R
R
R
R
R
11
10
9
8
Symbol
11
Device ID
Symbol
Device revision
8.9 SMBus register
Table 20.
SMBus Time-out register bit allocation
Bit
15
14
13
12
Symbol
RFU
Reset
0
0
0
0
0
0
0
0
Access
R
R
R
R
R
R
R
R
7
6
5
4
3
2
1
Bit
Symbol
STMOUT
Reset
Access
Table 21.
RFU
0
SALRT
0
0
0
0
0
0
0
0
R/W
R
R
R
R
R
R
R/W
SMBus Time-out register bit description
Bit
Symbol
Description
15:8
RFU
reserved; always 0
7
STMOUT
SMBus time-out.
0 — SMBus time-out is enabled (default)
1 — disable SMBus time-out
When either of the lock bits is set, this bit cannot be altered until unlocked.
6:1
RFU
reserved; always 0
0
SALRT
SMBus Alert.
0 — SMBus Alert is enabled (default)
1 — disable SMBus Alert
When either of the lock bits is set, this bit cannot be altered until unlocked.
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
19 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
9. Application design-in information
In a typical application, the SE98 behaves as a slave device and interfaces to the master
(or host) via the SCL and SDA lines. The host monitors the EVENT output pin, which is
asserted when the temperature reading exceeds the programmed values in the alarm
registers. The A0, A1 and A2 pins are directly connected to the shared SPD’s A0, A1 and
A2 pins, otherwise they must be pulled HIGH or LOW. The SDA and SCL serial interface
pins are open-drain and require pull-up resistors, and are able to sink a maximum current
of 3 mA with a voltage drop less than 0.4 V. Typical pull-up values for SCL and SDA are
10 kΩ, but the resistor values can be changed in order to meet the rise time requirement if
the capacitance load is too large due to routing, connectors, or multiple components
sharing the same bus.
slave
master
10 kΩ
(3×)
VDD
SCL
A0
A1
A2
HOST
CONTROLLER
SDA
SE98
EVENT
VSS
002aab282
Fig 12. Typical application
9.1 SE98 in memory module application
Figure 13 shows the SE98 being placed in the memory module application. The SE98 is
centered in the memory module to provide the function to monitor the temperature of the
DRAM. In the event of overheat, the SE98 triggers the EVENT output and the memory
controller can throttle the memory bus to slow the DRAM, or the CPU can increase the
refresh rate for the DRAM. The memory controller can also read the SE98 and watch the
DRAM thermal behavior.
DIMM
DRAM
SE98
DRAM
SMBus
MEMORY CONTROLLER
DRAM
DRAM
EVENT
CPU
002aac804
Fig 13. System application
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
20 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
9.2 Layout consideration
The SE98 does not require any additional components other than the host controller to
measure temperature. A 0.1 µF bypass capacitor between the VDD and VSS pins is
located as close as possible to the power and ground pins for noise protection.
9.3 Thermal considerations
In general, self-heating is the result of power consumption and not a concern, especially
with the SE98, which consumes very low power. In the event the SDA and EVENT pins
are heavily loaded with small pull-up resistor values, self-heating affects temperature
accuracy by approximately 0.5 °C.
Equation 1 is the formula to calculate the effect of self-heating:
T∆ = R th ( j-a ) × [ ( V DD × I DD ) + ( V OL1 × I OL1 ) + ( V OL2 × I OL2 ) ]
(1)
where:
T∆ = Tj − Tamb
Tj = junction temperature
Tamb = ambient temperature
Rth(j-a) = package thermal resistance
VOL1 = SDA output low voltage
VOL2 = EVENT output low voltage
IOL1 = SDA output current LOW
IOL2 = EVENT output current LOW.
10. Limiting values
Table 22. Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Symbol
Parameter
VDD
supply voltage
Conditions
Min
Max
Unit
−0.3
+4.2
V
Vn
voltage on any other pin
SDA, SCL, EVENT pins
−0.3
+4.2
V
VA0
voltage on pin A0
overvoltage input; A0 pin
−0.3
+10
V
Isink
sink current
at SDA, SCL, EVENT pins
−1
+50.0
mA
Vesd
electrostatic discharge
voltage
HBM
-
2500
V
MM
-
250
V
CDM
-
1000
V
Tj(max)
maximum junction
temperature
-
150
°C
Tstg
storage temperature
−65
+165
°C
[1]
In general, application of 10 V on the A0 pin would not damage the pin, but NXP Semiconductors does not
guarantee the overvoltage for this pin.
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
21 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
11. Characteristics
Table 23. Characteristics
VDD = 3.0 V to 3.6 V; Tamb = −20 °C to +125 °C; unless otherwise specified.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
Tlim(acc)
temperature limit accuracy
B-grade temperature accuracy;
VDD = 3.3 V ± 10 %
Tamb = 75 °C to 95 °C
−1.0
< ±0.5
+1.0
°C
Tamb = 40 °C to 125 °C
−2.0
< ±1
+2.0
°C
Tamb = −20 °C to +125 °C
−3.0
< ±2
+3.0
°C
Tamb = 75 °C to 95 °C
−2.0
< ±1
+2.0
°C
Tamb = 40 °C to 125 °C
−3.0
< ±2
+3.0
°C
C-grade temperature accuracy;
VDD = 3.3 V ± 10 %
−4.0
< ±3
+4.0
°C
Tres
temperature resolution
Tamb = −20 °C to +125 °C
-
0.25
-
°C
IDD(AV)
average supply current
-
-
250
µA
IDD(stb)
standby supply current
-
8
15
µA
SMBus inactive
Tconv
conversion period
-
100
-
ms
Ef(conv)
conversion rate error
percentage error in programmed
data
−30
-
+30
%
IL
leakage current
on A0, A1, A2 pins
-
1
-
µA
VDD
supply voltage
3.0
3.3
3.6
V
Table 24. SMBus DC characteristics
VDD = 3.0 V to 3.6 V; Tamb = −20 °C to +120 °C; unless otherwise specified. These specifications are guaranteed by design.
Symbol
Parameter
Conditions
Min
Typ
Max
Unit
VIH
HIGH-level input voltage
SCL, SDA;
VDD = 3.0 V to 3.6 V
2.2
-
-
V
VIL
LOW-level input voltage
SCL, SDA;
VDD = 3.0 V to 3.6 V
-
-
0.8
V
IOL(sink)EVENT_N
LOW-level output sink current on pin
EVENT
VOL = 0.4 V
1
-
-
mA
IOL(sink)(SDA)
LOW-level output sink current on pin
SDA
VOL = 0.6 V
6
-
-
mA
ILOH
HIGH-level output leakage current
VOH = VDD
-
-
1.0
µA
ILIH
HIGH-level input leakage current
VI = VDD or VSS
−1.0
-
+1.0
µA
ILIL
LOW-level input leakage current
VI = VDD or VSS
−1.0
-
+1.0
µA
Ci
input capacitance
SCL, SDA pins
-
5
10
pF
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
22 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
002aac157
300
IDD(AV)
(µA)
200
002aac158
16
IDD(stb)
(µA)
12
VDD = 3.0 V
3.3 V
3.6 V
VDD = 3.0 V
3.3 V
3.6 V
8
100
4
0
−50
−25
0
25
50
75
0
−50
125
100
Tamb (°C)
Fig 14. Supply current versus temperature
IOL(sink)EVENT_N
(mA)
25
50
75
125
100
Tamb (°C)
002aac160
20.0
VDD = 3.0 V
3.3 V
3.6 V
10.0
0
Fig 15. Standby supply current versus temperature
002aac159
15.0
−25
VDD = 3.0 V
3.3 V
3.6 V
15.0
IOL(sink)(SDA)
(mA)
10.0
5.0
5.0
0
−50
−25
0
25
50
75
0
−50
125
100
Tamb (°C)
Fig 16. EVENT sink current at 0.4 V versus temperature
−25
0
25
50
75
125
100
Tamb (°C)
Fig 17. EVENT sink current at 0.6 V versus temperature
002aac161
4
Temp
Error
(°C)
2
0
−2
−4
−50
−25
0
25
50
75
125
100
Tamb (°C)
Sample of 25 devices at VDD = 3.3 V
Fig 18. Temperature Error versus temperature
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
23 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
Table 25. SMBus AC characteristics
VDD = 3.0 V to 3.6 V; Tamb = −20 °C to +120 °C; unless otherwise specified. These specifications are guaranteed by design.
The AC specifications fully meet or exceed SMBus 2.0 specifications, but allow the bus to interface with the I2C-bus from DC
to 400 kHz.
Symbol
Parameter
Conditions
fSCL
SCL clock frequency
tLOW
LOW period of the SCL clock
10 % to 10 %
tHIGH
HIGH period of the SCL clock
90 % to 90 %
tBUF
bus free time between a STOP and
START condition
tHD;STA
hold time (repeated) START condition
tHD;DAT
data hold time
tSU;DAT
data set-up time
10 % of SDA to
90 % of SCL
Min
Typ
Max
Unit
0
-
400
kHz
1.3
-
-
µs
0.6
-
-
µs
4.7
-
-
µs
[1]
4.7
-
-
µs
[2]
300
-
-
ns
250
-
-
ns
250
-
-
ns
[3]
tSU;STA
set-up time for a repeated START
condition
tSU;STO
set-up time for STOP condition
0.6
-
-
µs
tr
rise time of both SDA and SCL signals
-
-
300
ns
tf
fall time of both SDA and SCL signals
-
-
300
ns
tf(o)
output fall time
tto(SMBus)
SMBus time-out time
[4]
[1]
Delay from SDA START to first SCL HIGH-to-LOW transition.
[2]
Delay from SCL HIGH-to-LOW transition to SDA edges.
[3]
Delay from SCL LOW-to-HIGH transition to restart SDA.
[4]
LOW period to reset SMBus.
tLOW
tr
tf
-
-
250
ns
25
-
35
ms
tHD;STA
SCL
tHD;STA
tHD;DAT
tHIGH
tSU;STA
tSU;STO
tSU;DAT
SDA
tBUF
P
S
S
P
002aab235
Fig 19. AC timing diagram
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
24 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
12. Package outline
TSSOP8: plastic thin shrink small outline package; 8 leads; body width 4.4 mm
SOT530-1
E
A
D
X
c
y
HE
v M A
Z
8
5
A2
A
(A3)
A1
pin 1 index
θ
Lp
L
detail X
1
4
e
w M
bp
0
2.5
5 mm
scale
DIMENSIONS (mm are the original dimensions)
UNIT
A
max.
A1
A2
A3
bp
c
D(1)
E(2)
e
HE
L
Lp
v
w
y
Z(1)
θ
mm
1.1
0.15
0.05
0.95
0.85
0.25
0.30
0.19
0.20
0.13
3.1
2.9
4.5
4.3
0.65
6.5
6.3
0.94
0.7
0.5
0.1
0.1
0.1
0.70
0.35
8°
0°
Notes
1. Plastic or metal protrusions of 0.15 mm maximum per side are not included.
2. Plastic or metal protrusions of 0.25 mm maximum per side are not included.
OUTLINE
VERSION
SOT530-1
REFERENCES
IEC
JEDEC
JEITA
EUROPEAN
PROJECTION
ISSUE DATE
00-02-24
03-02-18
MO-153
Fig 20. Package outline SOT530-1 (TSSOP8)
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
25 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
HVSON8: plastic thermal enhanced very thin small outline package; no leads;
8 terminals; body 3 x 3 x 0.85 mm
SOT908-1
0
1
2 mm
scale
X
B
D
A
E
A
A1
c
detail X
terminal 1
index area
e1
terminal 1
index area
e
v
w
b
1
4
M
M
C
C A B
C
y1 C
y
L
exposed tie bar (4×)
Eh
exposed tie bar (4×)
8
5
Dh
DIMENSIONS (mm are the original dimensions)
UNIT
A(1)
max.
A1
b
c
D(1)
Dh
E(1)
Eh
e
e1
L
v
w
y
y1
mm
1
0.05
0.00
0.3
0.2
0.2
3.1
2.9
2.25
1.95
3.1
2.9
1.65
1.35
0.5
1.5
0.5
0.3
0.1
0.05
0.05
0.1
Note
1. Plastic or metal protrusions of 0.075 mm maximum per side are not included.
OUTLINE
VERSION
SOT908-1
REFERENCES
IEC
JEDEC
JEITA
EUROPEAN
PROJECTION
ISSUE DATE
05-09-26
05-10-05
MO-229
Fig 21. Package outline SOT908-1 (HVSON8)
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
26 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
13. Soldering
This text provides a very brief insight into a complex technology. A more in-depth account
of soldering ICs can be found in Application Note AN10365 “Surface mount reflow
soldering description”.
13.1 Introduction to soldering
Soldering is one of the most common methods through which packages are attached to
Printed Circuit Boards (PCBs), to form electrical circuits. The soldered joint provides both
the mechanical and the electrical connection. There is no single soldering method that is
ideal for all IC packages. Wave soldering is often preferred when through-hole and
Surface Mount Devices (SMDs) are mixed on one printed wiring board; however, it is not
suitable for fine pitch SMDs. Reflow soldering is ideal for the small pitches and high
densities that come with increased miniaturization.
13.2 Wave and reflow soldering
Wave soldering is a joining technology in which the joints are made by solder coming from
a standing wave of liquid solder. The wave soldering process is suitable for the following:
• Through-hole components
• Leaded or leadless SMDs, which are glued to the surface of the printed circuit board
Not all SMDs can be wave soldered. Packages with solder balls, and some leadless
packages which have solder lands underneath the body, cannot be wave soldered. Also,
leaded SMDs with leads having a pitch smaller than ~0.6 mm cannot be wave soldered,
due to an increased probability of bridging.
The reflow soldering process involves applying solder paste to a board, followed by
component placement and exposure to a temperature profile. Leaded packages,
packages with solder balls, and leadless packages are all reflow solderable.
Key characteristics in both wave and reflow soldering are:
•
•
•
•
•
•
Board specifications, including the board finish, solder masks and vias
Package footprints, including solder thieves and orientation
The moisture sensitivity level of the packages
Package placement
Inspection and repair
Lead-free soldering versus PbSn soldering
13.3 Wave soldering
Key characteristics in wave soldering are:
• Process issues, such as application of adhesive and flux, clinching of leads, board
transport, the solder wave parameters, and the time during which components are
exposed to the wave
• Solder bath specifications, including temperature and impurities
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
27 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
13.4 Reflow soldering
Key characteristics in reflow soldering are:
• Lead-free versus SnPb soldering; note that a lead-free reflow process usually leads to
higher minimum peak temperatures (see Figure 22) than a PbSn process, thus
reducing the process window
• Solder paste printing issues including smearing, release, and adjusting the process
window for a mix of large and small components on one board
• Reflow temperature profile; this profile includes preheat, reflow (in which the board is
heated to the peak temperature) and cooling down. It is imperative that the peak
temperature is high enough for the solder to make reliable solder joints (a solder paste
characteristic). In addition, the peak temperature must be low enough that the
packages and/or boards are not damaged. The peak temperature of the package
depends on package thickness and volume and is classified in accordance with
Table 26 and 27
Table 26.
SnPb eutectic process (from J-STD-020C)
Package thickness (mm)
Package reflow temperature (°C)
Volume (mm3)
< 350
≥ 350
< 2.5
235
220
≥ 2.5
220
220
Table 27.
Lead-free process (from J-STD-020C)
Package thickness (mm)
Package reflow temperature (°C)
Volume (mm3)
< 350
350 to 2000
> 2000
< 1.6
260
260
260
1.6 to 2.5
260
250
245
> 2.5
250
245
245
Moisture sensitivity precautions, as indicated on the packing, must be respected at all
times.
Studies have shown that small packages reach higher temperatures during reflow
soldering, see Figure 22.
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
28 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
maximum peak temperature
= MSL limit, damage level
temperature
minimum peak temperature
= minimum soldering temperature
peak
temperature
time
001aac844
MSL: Moisture Sensitivity Level
Fig 22. Temperature profiles for large and small components
For further information on temperature profiles, refer to Application Note AN10365
“Surface mount reflow soldering description”.
14. Abbreviations
Table 28.
Abbreviations
Acronym
Description
ADC
Analog-to-Digital Converter
ARA
Alert Response Address
CDM
Charged Device Model
DIMM
Dual In-line Memory Module
HBM
Human Body Model
I2C-bus
Inter IC bus
LSB
Least Significant Bit
MM
Machine Model
MSB
Most Significant Bit
SO-DIMM
Small Outline Dual In-line Memory Module
POR
Power-On Reset
SMBus
System Management Bus
SPD
Serial Presence Detect
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
29 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
15. Revision history
Table 29.
Revision history
Document ID
Release date
Data sheet status
Change notice
Supersedes
SE98_2
20080107
Product data sheet
-
SE98_1
Modifications:
•
The format of this data sheet has been redesigned to comply with the new identity guidelines of
NXP Semiconductors.
•
•
•
•
•
Legal texts have been adapted to the new company name where appropriate.
Section 1 “General description” re-written
Section 2 “Features” re-written
Table 1 “Ordering information”: removed type numbers SE98PW/1 and SE98TK/1
Section 6 “Pinning information”:
– changed pin name “VCC” to “VDD”; changed pin name “GND” to “VSS”
– deleted SE98PW/1 from Figure 2 “Pin configuration for TSSOP8”
– deleted SE98TK/1 from Figure 3 “Pin configuration for HVSON8”
•
•
•
•
•
Table 2 “Pin description”: added Table note 1 and its reference at pin A0
Figure 5 “EVENT output for ‘Interrupt’, ‘Comparator’, and ‘Critical Temp only’ modes” modified
Section 7.5 “Power-up default condition” re-written
Added (new) Section 7.6 “Device initialization”
Table 5 “Capability register (address 00h) bit allocation”:
– deleted Table note 1 and its reference
– changed Reset value for bit 1 from (reference to Table note 1) to “0”
•
•
•
•
•
•
SE98_1
(9397 750 14649)
Table 6 “Capability register (address 00h) bit description”: description of bit HACC modified
Figure 11 “Hysteresis: how it works” modified
Section 9 “Application design-in information” re-written
Table 22 “Limiting values” re-written
Table 23 “Characteristics”: added descriptive text below table’s title
Titles of Figure 14, Figure 15, Figure 16 and Figure 17 re-written
20060510
Product data sheet
-
SE98_2
Product data sheet
-
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
30 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
16. Legal information
16.1 Data sheet status
Document status[1][2]
Product status[3]
Definition
Objective [short] data sheet
Development
This document contains data from the objective specification for product development.
Preliminary [short] data sheet
Qualification
This document contains data from the preliminary specification.
Product [short] data sheet
Production
This document contains the product specification.
[1]
Please consult the most recently issued document before initiating or completing a design.
[2]
The term ‘short data sheet’ is explained in section “Definitions”.
[3]
The product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple devices. The latest product status
information is available on the Internet at URL http://www.nxp.com.
16.2 Definitions
Draft — The document is a draft version only. The content is still under
internal review and subject to formal approval, which may result in
modifications or additions. NXP Semiconductors does not give any
representations or warranties as to the accuracy or completeness of
information included herein and shall have no liability for the consequences of
use of such information.
Short data sheet — A short data sheet is an extract from a full data sheet
with the same product type number(s) and title. A short data sheet is intended
for quick reference only and should not be relied upon to contain detailed and
full information. For detailed and full information see the relevant full data
sheet, which is available on request via the local NXP Semiconductors sales
office. In case of any inconsistency or conflict with the short data sheet, the
full data sheet shall prevail.
16.3 Disclaimers
General — Information in this document is believed to be accurate and
reliable. However, NXP Semiconductors does not give any representations or
warranties, expressed or implied, as to the accuracy or completeness of such
information and shall have no liability for the consequences of use of such
information.
Right to make changes — NXP Semiconductors reserves the right to make
changes to information published in this document, including without
limitation specifications and product descriptions, at any time and without
notice. This document supersedes and replaces all information supplied prior
to the publication hereof.
Suitability for use — NXP Semiconductors products are not designed,
authorized or warranted to be suitable for use in medical, military, aircraft,
space or life support equipment, nor in applications where failure or
malfunction of an NXP Semiconductors product can reasonably be expected
to result in personal injury, death or severe property or environmental
damage. NXP Semiconductors accepts no liability for inclusion and/or use of
NXP Semiconductors products in such equipment or applications and
therefore such inclusion and/or use is at the customer’s own risk.
Applications — Applications that are described herein for any of these
products are for illustrative purposes only. NXP Semiconductors makes no
representation or warranty that such applications will be suitable for the
specified use without further testing or modification.
Limiting values — Stress above one or more limiting values (as defined in
the Absolute Maximum Ratings System of IEC 60134) may cause permanent
damage to the device. Limiting values are stress ratings only and operation of
the device at these or any other conditions above those given in the
Characteristics sections of this document is not implied. Exposure to limiting
values for extended periods may affect device reliability.
Terms and conditions of sale — NXP Semiconductors products are sold
subject to the general terms and conditions of commercial sale, as published
at http://www.nxp.com/profile/terms, including those pertaining to warranty,
intellectual property rights infringement and limitation of liability, unless
explicitly otherwise agreed to in writing by NXP Semiconductors. In case of
any inconsistency or conflict between information in this document and such
terms and conditions, the latter will prevail.
No offer to sell or license — Nothing in this document may be interpreted
or construed as an offer to sell products that is open for acceptance or the
grant, conveyance or implication of any license under any copyrights, patents
or other industrial or intellectual property rights.
16.4 Trademarks
Notice: All referenced brands, product names, service names and trademarks
are the property of their respective owners.
I2C-bus — logo is a trademark of NXP B.V.
17. Contact information
For additional information, please visit: http://www.nxp.com
For sales office addresses, send an email to: [email protected]
SE98_2
Product data sheet
© NXP B.V. 2008. All rights reserved.
Rev. 02 — 7 January 2008
31 of 32
SE98
NXP Semiconductors
SO-DIMM SMBus/I2C-bus temperature sensor
18. Contents
1
2
2.1
2.2
3
4
5
6
6.1
6.2
7
7.1
7.2
7.3
7.3.1
7.3.2
7.4
7.5
7.6
7.7
7.8
7.9
8
8.1
8.2
8.3
8.4
8.5
8.5.1
8.5.2
8.5.3
8.6
8.7
8.8
8.9
9
9.1
9.2
9.3
10
11
12
13
General description . . . . . . . . . . . . . . . . . . . . . . 1
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
General features . . . . . . . . . . . . . . . . . . . . . . . . 2
Temperature sensor features . . . . . . . . . . . . . . 2
Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Ordering information . . . . . . . . . . . . . . . . . . . . . 2
Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pinning information . . . . . . . . . . . . . . . . . . . . . . 4
Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 4
Functional description . . . . . . . . . . . . . . . . . . . 5
Serial bus interface . . . . . . . . . . . . . . . . . . . . . . 5
Slave address . . . . . . . . . . . . . . . . . . . . . . . . . . 5
EVENT output. . . . . . . . . . . . . . . . . . . . . . . . . . 5
Alarm window . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Critical trip. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Conversion rate. . . . . . . . . . . . . . . . . . . . . . . . . 6
Power-up default condition . . . . . . . . . . . . . . . . 7
Device initialization . . . . . . . . . . . . . . . . . . . . . . 7
SMBus Time-out . . . . . . . . . . . . . . . . . . . . . . . . 7
SMBus Alert . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
SMBus/I2C-bus interface . . . . . . . . . . . . . . . . . 8
Register descriptions . . . . . . . . . . . . . . . . . . . 11
Register overview . . . . . . . . . . . . . . . . . . . . . . 11
Capability register (00h, 16-bit read-only). . . . 12
Configuration register (01h, 16-bit read/write) 13
Temperature format . . . . . . . . . . . . . . . . . . . . 16
Temperature Trip Point registers . . . . . . . . . . . 16
Upper Boundary Alarm Trip register (16-bit
read/write). . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Lower Boundary Alarm Trip register (16-bit
read/write). . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Critical Alarm Trip register (16-bit read/write) . 17
Temperature register (16-bit read-only) . . . . . 18
Manufacturer’s ID register (16-bit read-only) . 18
Device ID register . . . . . . . . . . . . . . . . . . . . . . 19
SMBus register . . . . . . . . . . . . . . . . . . . . . . . . 19
Application design-in information . . . . . . . . . 20
SE98 in memory module application . . . . . . . 20
Layout consideration. . . . . . . . . . . . . . . . . . . . 21
Thermal considerations . . . . . . . . . . . . . . . . . 21
Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . 21
Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . 22
Package outline . . . . . . . . . . . . . . . . . . . . . . . . 25
Soldering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
13.1
13.2
13.3
13.4
14
15
16
16.1
16.2
16.3
16.4
17
18
Introduction to soldering. . . . . . . . . . . . . . . . .
Wave and reflow soldering . . . . . . . . . . . . . . .
Wave soldering. . . . . . . . . . . . . . . . . . . . . . . .
Reflow soldering. . . . . . . . . . . . . . . . . . . . . . .
Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . .
Revision history . . . . . . . . . . . . . . . . . . . . . . .
Legal information . . . . . . . . . . . . . . . . . . . . . .
Data sheet status . . . . . . . . . . . . . . . . . . . . . .
Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . .
Disclaimers. . . . . . . . . . . . . . . . . . . . . . . . . . .
Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . .
Contact information . . . . . . . . . . . . . . . . . . . .
Contents. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
27
27
27
28
29
30
31
31
31
31
31
31
32
Please be aware that important notices concerning this document and the product(s)
described herein, have been included in section ‘Legal information’.
© NXP B.V. 2008.
All rights reserved.
For more information, please visit: http://www.nxp.com
For sales office addresses, please send an email to: [email protected]
Date of release: 7 January 2008
Document identifier: SE98_2