ADIS16201 Analog Devices, Inc., ADIS16201 Datasheet - Page 30

• Manufacturer Part Number: ADIS16201
• Description: Programmable Dual-axis Inclinometer/accelerometer
• Manufacturer: Analog Devices, Inc.

ADIS16201
BANDGAP REFERENCE
The ADIS16201 provides an on-chip band gap reference of
2.5 V, which is utilized by the on-board ADC and DAC. This
internal reference also appears on the VREF pin. This reference
can be connected to external circuits in the system. An external
buffer would be required because of the low drive capability of
the VREF output.
POWER-ON RESET OPERATION
An internal power-on reset (POR) is implemented internally to
the ADIS16201. For VDD below 2.35 V, the internal POR holds
the ADIS16201 in reset. As VDD rises above 2.35 V, an internal
timer times out for typically 130 ms before the part is released
from reset. The user must ensure that the power supply has
reached a stable 3.0 V minimum level by this time. Likewise,
on power-down, the internal POR holds the ADIS16201 in reset
until VDD has dropped below 2.35 V. Figure 40 illustrates the
operation of the internal POR in detail.
POR
SECOND-LEVEL ASSEMBLY
The ADIS16201 can be attached to the second-level assembly
board using SN63 (or equivalent) or lead-free solder. Figure 41
and Table 32 provide acceptable solder reflow profiles for each
solder type. Note: These profiles may not be the optimum
profile for the user’s application. In no case should 260°C be
exceeded. It is recommended that the user develop a reflow
profile based upon the specific application. In general, keep in
mind that the lowest peak temperature and shortest dwell time
above the melt temperature of the solder result in less shock and
stress to the product. In addition, evaluating the cooling rate
and peak temperature can result in a more reliable assembly.
VDD
2.35V TYP
Figure 40. Internal Power-On Reset Operation
130ms TYP
Rev. A | Page 30 of 32
Table 32.
Profile Feature
Average Ramp Rate (T
Preheat
Minimum Temperature (T
Maximum Temperature (T
Time (T
T
Ramp-Up Rate
Time Maintained Above
Liquidous (T
Liquidous Temperature (T
Time (t
Peak Temperature (T
Time Within 5°C of Actual Peak
Temperature (t
Ramp-Down Rate
Time 25°C to Peak Temperature
EXAMPLE PAD LAYOUT
SMAX
T
T
P
L
T
to T
SMIN
L
SMIN to
0.670 BSC
)
(12 PLCS)
1.127 BSC
(16 PLCS)
T
L
SMAX
L
T
)
SMAX
Figure 41. Acceptable Solder Reflow Profiles
p
)
PREHEAT
) (t
t
25°C TO PEAK
Figure 42. Example Pad Layout
t
s
S
P
)
)
L
to T
1.178 BSC
(8 PLCS)
SMAX
SMIN
L
P
)
)
RAMP-UP
)
)
TIME
RAMP-DOWN
Condition
Sn63/Pb37
3°C/sec max
100°C
150°C
60 sec to
120 sec
3°C/sec
183°C
60 sec to
150 sec
240°C +
0°C/–5°C
10 sec to
30 sec
6°C/sec max
6 min max
t
P
7.873 BSC
t
(2 PLCS)
L
0.500 BSC
(16 PLCS)
CRITICAL ZONE
Pb-Free
3°C/sec max
150°C
200°C
60 sec to
150 sec
3°C/sec
217°C
60 sec to
150 sec
260°C +
0°C/–5°C
20 sec to
40 sec
6°C/sec max
8 min max
T
L
TO T
P