Rainbow Electronics MAX6871 - Manual (Page 15)

where V TH is the desired threshold voltage and x is the
decimal code for the desired threshold (Table 3).
IN3–IN6
IN3–IN6 offer positive voltage detectors monitor volt-
ages from +1V to +5.5V in 20mV increments, or +0.5V
to +3.05V in 10mV increments. Use the following equa-
tions to set the threshold voltages for IN_:
where V TH is the desired threshold voltage and x is the
decimal code for the desired threshold (Table 4). For
the +1V to +5.5V range, x must equal 225 or less, oth-
erwise the threshold exceeds the maximum operating
voltage of IN3–IN6.
x
V V
V
for V to V range
TH = + +
− .
.
. .
0 5
0 01
0 5 3 05
x
V V
V
for V to V range
TH = + +
−
.
.
1
0 02
1 5 5
x
V V
V
for V to V range
TH = + +
− .
.
. .
1 25
0 025
1 25 7 625
x
V V
V
for V to V range
TH = + +
− .
.
. .
2 5
0 05
2 5 15 25
x
V V
V
for V to V range
TH
=
( )
− −
− − .
.
. .
1 25
0 025
1 25 7 625
x
V V
V
for V to V range
TH =
( )
−
− −
−
.
.
. .
2 5
0 05
2 5 15 25
MAX6870/MAX6871
EEPROM-Programmable Hex/Quad
Power-Supply Sequencers/Supervisors with ADC
______________________________________________________________________________________ 15
Table 2. IN1 Threshold Settings
REGISTER
ADDRESS
EEPROM
MEMORY
ADDRESS
BIT
RANGE
DESCRIPTION
00h 8000h [7:0]
IN1 primary undervoltage detector threshold (V1A) (see equations in the High Voltage Input
(IN1) section).
06h 8006h [7:0]
IN1 secondary undervoltage/overvoltage detector threshold (V1B) (see equations in the
High Voltage Input (IN1) section).
0Ch 800Ch [0]
IN1 secondary overvoltage/undervoltage selection.
0 = overvoltage threshold. 1 = undervoltage threshold.
0Dh 800Dh [0]
IN 1 r ang e sel ecti on.
0 = 2.5V to 13.2V r ang e i n 50m V i ncr em ents. 1 = 1.25V to 7.625V r ang e i n 25m V i ncr em ents.
Table 3. IN2 Threshold Settings
REGISTER
ADDRESS
EEPROM
MEMORY
ADDRESS
BIT
RANGE
DESCRIPTION
01h 8001h [7:0]
IN2 primary undervoltage detector threshold (V2A) (see equations in the Bipolar Voltage
Input (IN2) section).
07h 8007h [7:0]
IN2 secondary undervoltage/overvoltage detector threshold (V2B) (see equations in the
Bipolar Voltage Input (IN2) section).
0Ch 800Ch [1]
IN2 secondary overvoltage/undervoltage selection.
0 = overvoltage threshold. 1 = undervoltage threshold.
0Dh 800Dh [7:6]
IN2 range selection.
00 = -2.5V to -15.25V range in 50mV increments.
01 = -1.25V to -7.625V range in 25mV increments.
10 = +2.5V to +15.25V range in 50mV increments.
11 = +1.25V to +7.625V range in 25mV increments.