Rainbow Electronics MAX6512 - Manual (Page 4)

Detailed Description
The MAX6511/MAX6512/MAX6513 fully integrated tem-
perature switches incorporate a precision bandgap ref-
erence, a conversion block, a current source, and a
comparator (Figure 1). These devices use an external
P-N junction as the temperature-sensing element. They
steer bias currents through the external diode, measure
the forward voltages, and compute the temperature
using a precision chopper stabilized amplifier.
Resistance values of less than 100 Ω in series with the
external sense junction will result in trip-point errors
<1°C. The MAX6511/MAX6512/MAX6513 provide noise
immunity by integration and oversampling of the diode
voltage, but good design practice includes routing the
DXP and DXN lines away from noise sources, such as
high-speed digital lines, switching regulators, induc-
tors, and transformers. The DXP and DXN traces
should be paired together and surrounded by ground
plane whenever possible.
In applications where the temperature changes rapidly,
the measured temperature will be approximately equal
to the average value of the temperature during the
measurement period.
The MAX6512 has an active-low, open-drain output struc-
ture that can only sink current. The MAX6511 has an active-
low CMOS output structure, and the MAX6513 has an
active-high CMOS output.
The MAX6511/MAX6512/MAX6513 are available with
preset temperature thresholds from +45°C to +125°C in
10°C increments.
MAX6511/MAX6512/MAX6513
Low-Cost, Remote SOT Temperature Switches
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Pin Description
PIN
MAX6511
MAX6512
MAX6513
NAME FUNCTION
1 1 V DD
Power-Supply Input, +3.0V to +5.5V . Bypass V DD to GND with a 0.1µF
capacitor.
2 2 GND Ground
3 3 HYST Hysteresis Selection. Hysteresis is 10°C for HYST = V DD , 5 °C for HYST = GND.
4 — TOVER
CMOS Active-Low Output (MAX6511) or Open-Drain Active-Low Output
(MAX6512). TOVER goes low when the temperature exceeds the factory-
programmed temperature threshold. This pin can only sink current in the
MAX6512.
— 4 TOVER
CMOS Active-High Output (MAX6513). TOVER goes high when the temperature
exceeds the factory-programmed temperature threshold.
5 5 DXN
This pin connects to the negative (cathode) terminal of the external P-N sense
junction. DXN must be connected to GND.
6 6 DXP
This pin connects to the positive (anode) terminal of the external P-N sense
junction.
DXP
DXN
TEMPERATURE
CONVERSION
BANDGAP
VOLTAGE
REFERENCE
COMPAR-
ATOR
LATCH TOVER
Figure 1. Functional Block Diagram