MIC280 MICREL [Micrel Semiconductor], MIC280 Datasheet - Page 22

• Manufacturer Part Number: MIC280
• Description: Precision IttyBitty Thermal Supervisor
• Manufacturer: MICREL [Micrel Semiconductor]

MIC280
4. Due to the small currents involved in the mea-
5. In general, wider traces for the ground and T1
on these devices. To allow for this, the MIC280
has superb rejection of noise appearing from
collector to GND.
surement of the remote diode’s ∆V
important to adequately clean the PC board after
soldering to prevent current leakage. This is
most likely to show up as an issue in situations
where water-soluble soldering fluxes are used.
lines will help reduce susceptibility to radiated
noise (wider traces are less inductive). Use trace
widths and spacing of 10 mils wherever possible
and provide a ground plane under the MIC280
and under the connections from the MIC280 to
the remote diode. This will help guard against
stray noise pickup.
SERIAL BUS
HOST
TO
3V to 3.6V
10k
3 ×
Figure 7. V
Figure 6. Guard Traces/Kelvin Ground Returns
1
2
3
VDD
GND
T1
BE
MIC280
, it is
5
4
6
DD
DATA
DATA
CLK
/INT
/INT
CLK
Decoupling for Very Noisy Supplies
MIC280
100Ω
6
5
4
GND
VDD
T1
22
1
3
2
REMOTE DIODE (T1)
GUARD/RETURN
GUARD/RETURN
6. Always place a good quality power supply
7. When the MIC280 is being powered from par-
0.1µF
ceramic
bypass capacitor directly adjacent to, or under-
neath, the MIC280. This should be a 0.1 µF ce-
ramic capacitor. Surface-mount parts provide the
best bypassing because of their low inductance.
ticularly noisy power supplies, or from supplies
which may have sudden high-amplitude spikes
appearing on them, it can be helpful to add ad-
ditional power supply filtering. This should be
implemented as a 100Ω resistor in series with
the part’s V
capacitor from V
4.7µF
1800pF
DD
pin, and a 4.7 µF, 6.3V electrolytic
DD
to GND. See Figure 7.
2N3906/
CPU DIODE
November 2004