LT6700IDCB-1#PBF Linear Technology, LT6700IDCB-1#PBF Datasheet - Page 16

• Manufacturer Part Number: LT6700IDCB-1#PBF
• Manufacturer: Linear Technology

Specifications of LT6700IDCB-1#PBF

• Number Of Elements: 2
• Output Type: Open Collector
• Single Supply Voltage (typ): 3/5/9/12/15V
• Dual Supply Voltage (typ): Not RequiredV
• Supply Current (max): 0.011mA
• Power Supply Requirement: Single
• Single Supply Voltage (min): 1.4V
• Single Supply Voltage (max): 18V
• Dual Supply Voltage (min): Not RequiredV
• Dual Supply Voltage (max): Not RequiredV
• Operating Temp Range: -40C to 85C
• Operating Temperature Classification: Industrial
• Mounting: Surface Mount
• Pin Count: 6
• Package Type: DFN EP
• Lead Free Status / Rohs Status: Compliant

APPLICATIONS INFORMATION
LT6700-1/LT6700-2/LT6700-3/
LT6700HV-1/LT6700HV-2/
LT6700HV-3
ing into spec” condition, as with the examples in Figure 1),
the nominal resistor values are selected as follows:
The worst-case variance of the trip-points is related to
the specifi ed threshold limits of the LT6700/LT6700HV
device and the basic tolerance of divider resistors used.
For resistor tolerance R
case trip-point voltage (either V
predicted as follows (italicized values are taken from the
datasheet, expressed in volts):
Max dev V
/ V
Max dev V
/ V
16
TRIPnom
TRIPnom
R1 ≤ 400k (this sets the divider current >> I
R2 = R1 • (1.02 • V
R3 = R1 • (2.54 • V
TRIP↓
TRIP↑
] + 1.25 • ( V
] + 1.27 • ( V
= ±V
= ±V
TRIPnom
TRIPnom
H
H
TH(R)max
TH(F)max
/V
TOL
– 1.02 • V
L
– 1)
(e.g. 0.01 for 1%), the worst-
• {2 • R
• {2 • R
– V
H
– V
3.3μF
or V
H
TOL
TH(F)min
TOL
TH(R)min
/V
Figure 2. Micropower Thermostat/Temperature Alarm
L
L
• [(V
R
R
*RESISTANCE MAY REQUIRE OPTIMIZATION FOR OPERATION
HYSTERESIS ZONE ≈0.4°C
) deviations can be
)
OVER INTENDED R
• [(V
TH
SET
R
= 1M (e.g., YSI 44015, 1.00MΩ AT 25°C)
TH
= R
TRIPnom
)}
2 • V
)}
TRIPnom
TH
AT T
B
REF
R
T
SET
of inputs)
SET
– 0.39)
TH
– 0.4)
499k
499k
AND V
0.1μF
SUPPLY
+INA
–INB OUTB
LT6700-1
GND
V
S
OUTA
Generating an External Reference Signal
In some applications, it would be advantageous to have
access to a signal that is directly related to the internal
400mV reference, even though the reference itself is not
available externally. This can be accomplished to a reason-
able degree by using an inverting comparator section as
a “bang-bang” servo, establishing a nominal voltage, on
an integration capacitor, that is scaled to the reference.
This method is used in Figure 2, where the reference level
has been doubled to drive a resistor bridge. The section
B output cycles on and off to swing the section B input
between its hysteresis trip points as the load capacitor
charges and discharges in a shallow, controlled fashion.
The multiplied reference signal also contains ripple that is
the hysteresis multiplied by the same factor, so additional
fi ltering is performed at the sense node of the bridge to
prevent comparator chatter in the section A comparator,
which is performing the actual conditional decision for
the circuit.
RANGES
10k
6700123 F02
220k
220k*
3.3μF
1.4V TO 18V
(I
T < T
S
≈ 10μA)
SET
6700123ff