MAX9118EXK+T Maxim Integrated Products, MAX9118EXK+T Datasheet - Page 11

• Manufacturer Part Number: MAX9118EXK+T
• Description: IC COMPARATOR BTR SC70-5
• Manufacturer: Maxim Integrated Products
• Series: Beyond-the-Rails™r
• Type: with Voltage Referencer

Specifications of MAX9118EXK+T

• Number Of Elements: 1
• Output Type: CMOS, Open-Drain, Rail-to-Rail, TTL
• Voltage - Supply: 1.6 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 6-TSSOP (5 lead), SC-88A, SOT-353
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: MAX9118EXK+T; MAX9118EXK+TTR

2) Choose the hysteresis band required (V
3) Calculate R1 according to the following equation:
4) Choose the trip point for V
5) Calculate R2 as follows:
For this example, choose an 8.66kΩ standard 1% value.
6) Verify the trip voltages and hysteresis as follows:
Figure 2. Threshold Hysteresis Band
OUT
MAX9117 (V
we choose I
are 1.2MΩ and 3.8MΩ. Choose a 1.2MΩ standard
value for R3.
example, choose 50mV.
For this example, insert the values:
V
for V
the comparator switches its output from low to high
as V
choose 3V.
R2 = 1 / [V
R2 = 1 / [3.0V / (1.252V
V
V
Hysteresis = V
IN+
IN-
THR
IN
IN
V
V
THR
THF
rising: V
falling: V
IN
IN
(1 / 1.2MΩ)] = 8.655kΩ
> V
rising). This is the threshold voltage at which
rises above the trip point. For this example,
R1 = 1.2MΩ (50mV / 5V) = 12kΩ
REF
+ (1 / R3)] = 3V
THR
V
THR
HB
THF
R3
REF
SC70, 1.6V, Nanopower, Beyond-the-Rails
✕
THR
R1 = R3 (V
/ (V
______________________________________________________________________________________
(R1 + R3) / R3, (V
= 1µA, then the two resistor values
= V
= V
= 1.252V) and V
REF
- V
REF
THR
THRESHOLDS
THF
HYSTERESIS
✕
Comparators With/Without Reference
BAND
✕
✕
R1) - (1 / R1) - (1 / R3)]
- (R1
HB
12kΩ) - (1 / 12kΩ) -
= 50mV
R1 [(1 / R1) + (1 / R2)
IN
/ V
rising (V
✕
CC
V
THR
CC
)
CC
/ R3) = 2.95V
is the trip point
THR
= +5V, and if
HB
) such that
). For this
The MAX9118/MAX9120 have a 4mV internal hysteresis
band. They have open-drain outputs and require an
external pullup resistor (Figure 4). Additional hysteresis
can be generated using positive feedback, but the for-
mulas differ slightly from those of the MAX9117/
MAX9119. Use the following procedure to calculate
resistor values.
1) Select R3 according to the formulas R3 = V
2) Choose the hysteresis band required (V
3) Calculate R1 according to the following equation:
4) Choose the trip point for V
5) Calculate R2 as follows:
6) Verify the trip voltages and hysteresis as follows:
Additional Hysteresis (MAX9118/MAX9120)
Figure 3. MAX9117/MAX9119 Additional Hysteresis
R
V falling
V ri
V
IN
IN
2 1
THF
or R3 = (V
the two resulting resistor values.
the trip point for V
age at which the comparator switches its output
from low to high as V
=
sin :
V
=
IN
/
V
⎡
⎢
⎢
⎣
g
⎛
⎜
⎝
REF
:
V
REF
V
V
×
R1
THR
CC
THR
R1 = (R3 + R4) (V
R
Hysteresis = V
×
1
- V
=
⎛
⎜
⎝
R2
R
R
1
1
V
REF
1
⎞
⎟
⎠
IN
REF
−
+
R
rising). This is the threshold volt-
R
V
) / 1µA - R4. Use the smaller of
IN
1
1
REF
1
2
×
−
rises above the trip point.
+
R
R
1
R3
R
3
1
THR
IN
3
⎤
⎥
⎥
⎦
⎛
⎜
⎝
HB
R
1
+
1
V
V
V
rising (V
1
CC
CC
EE
R
- V
+
/ V
4
R
⎞
⎟
⎠
THF
1
CC
2
−
OUT
MAX9117
MAX9119
R
+
)
3
THR
R
HB
1
3
R
+
1
⎞
⎟
⎠
).
) (V
REF
R
4
THR
×
/ 1µA
V
CC
11
is