MAX1617MEE-T Maxim Integrated Products, MAX1617MEE-T Datasheet - Page 13

• Manufacturer Part Number: MAX1617MEE-T
• Description: Board Mount Temperature Sensors
• Manufacturer: Maxim Integrated Products

Specifications of MAX1617MEE-T

• Full Temp Accuracy: +/- 3.5 C, +/- 5 C
• Package / Case: QSOP-16
• Digital Output - Bus Interface: Serial (2-Wire)
• Digital Output - Number Of Bits: 7 bit + Sign
• Maximum Operating Temperature: + 125 C
• Minimum Operating Temperature: - 55 C
• Output Type: Digital
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

To check for internal bus collisions, read the status
byte. If the least significant seven bits are ones, discard
the data and read the status byte again. The status bits
LHIGH, LLOW, RHIGH, and RLOW are refreshed on the
SMBus clock edge immediately following the stop con-
dition, so there is no danger of losing temperature-relat-
ed status data as a result of an internal bus collision.
The OPEN status bit (diode continuity fault) is only
refreshed at the beginning of a conversion, so OPEN
Table 5. Configuration-Byte Bit
Assignments
Table 6. Status-Byte Bit Assignments
* These flags stay high until cleared by POR, or until the status
byte register is read.
7 (MSB)
(MSB)
(LSB)
BIT
BIT
5–0
7
6
5
4
3
2
1
0
6
RHIGH*
LHIGH*
RLOW*
LLOW*
OPEN*
NAME
BUSY
NAME
RFU
RFU
MASK
STOP
RUN/
RFU
______________________________________________________________________________________
A high indicates that the ADC is busy
converting.
A high indicates that the local high-
temperature alarm has activated.
A high indicates that the local low-
temperature alarm has activated.
A high indicates that the remote high-
temperature alarm has activated.
A high indicates that the remote low-
temperature alarm has activated.
A high indicates a remote-diode conti-
nuity (open-circuit) fault.
Reserved for future use (returns 0)
Reserved for future use (returns 0)
STATE
POR
0
0
0
Masks all ALERT inter-
rupts when high.
Standby mode control
bit. If high, the device
immediately stops con-
verting and enters stand-
by mode. If low, the
device converts in either
one-shot or timer mode.
Reserved for future use
Remote/Local Temperature Sensor
FUNCTION
FUNCTION
with SMBus Serial Interface
data is lost. The ALERT interrupt latch is independent of
the status byte register, so no false alerts are generat-
ed by an internal bus collision.
When auto-converting, if the THIGH and TLOW limits
are close together, it’s possible for both high-temp and
low-temp status bits to be set, depending on the
amount of time between status read operations (espe-
cially when converting at the fastest rate). In these cir-
cumstances, it’s best not to rely on the status bits to
indicate reversals in long-term temperature changes
and instead use a current temperature reading to
establish the trend direction.
The conversion rate register (Table 7) programs the
time interval between conversions in free-running auto-
convert mode. This variable rate control reduces the
supply current in portable-equipment applications. The
conversion rate byte’s POR state is 02h (0.25Hz). The
MAX1617 looks only at the 3 LSB bits of this register, so
the upper 5 bits are “don’t care” bits, which should be
set to zero. The conversion rate tolerance is ±25% at
any rate setting.
Valid A/D conversion results for both channels are
available one total conversion time (125ms nominal,
156ms maximum) after initiating a conversion, whether
conversion is initiated via the RUN/STOP bit, hardware
STBY pin, one-shot command, or initial power-up.
Changing the conversion rate can also affect the delay
until new results are available. See Table 8.
Table 7. Conversion-Rate Control Byte
DATA
08h to
00h
01h
02h
03h
04h
05h
06h
07h
FFh
CONVERSION
0.0625
RATE
0.125
(Hz)
0.25
RFU
0.5
1
2
4
8
Conversion Rate Byte
(µA typ, at V
AVERAGE SUPPLY
CURRENT
128
225
425
30
33
35
48
70
—
CC
= 3.3V)
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