Rainbow Electronics LM40 - Manual (Page 23)

2.0 Register Set
(Continued)
Analog Input Voltage Mapping
Sensor
Number
(SNUM) Voltage Input
Input Voltage
for Nominal
Reading
(code 384 or
180h)
Maximum
Input Voltage
(code 510.5)
Register
Reading at
Maximum
Voltage
Minimum
Input Voltage
Register
Reading at
Minimum
Voltage Resolution
0 +2.5V 2.5V 3.32V to 6V 1FFh -0.5V to
3.26mV
00h 6.51mV
1 +1.2V 1.2V 1.6V to 6V 1FFh -0.5V to
2.63mV
00h 5.86mV
2 +3.3V_SBY
(V+)
3.3V 4.39V to 6V 1FFh 3.0V 15Dh 8.59mV
3 +5V 5V 6.65V 1FFh -0.5V to
6.51mV
00h 13.02mV
4 +12V 12V 15.95V to 16V 1FFh -0.5V to
15.63mV
00h 31.25mV
2.10.4 Voltage Control (Addr: 010 010; 12h)
This register is set to the reset value by a Device Reset.
Reg
Add
Register
Name
R/
W
P
O
R
Val
Bit
15
MSb
Bit
14
Bit
13
Bit
12
Bit
11
Bit
10
Bit
9
Bit
8
Bit
7
Bit
6
Bit
5
Bit
4
Bit
3
Bit
2
Bit
1
Bit
0
LSb
010 010
Voltage
Control
R/
W
1Fh
Reserved
EN4 EN3 EN2 EN1 EN0 ATE
Low Rate Function
(Read Only)
0 0 0 0 0 1 1 1 1 1
Bit Type Description
4-0 RO Low Rate Function This function is not supported by the LM40 and therefore this field is read only.
5 R/W ATE (Attention Enable). When set, this bit enables an Attention Request signal to be generated by the
LM40, if one or more EN0-EN4 bits of this register are set.
0: Attention Request disabled (from enabled Temperature Sensor- default)
1: Attention Request enabled
6 R/W EN0 (Enable Sensor 0). When this bit is set, the Voltage Sensor 0 is enabled for voltage measurements.
0: Voltage Sensor disabled (default)
1: Voltage Sensor enabled
10-7 R/W EN1-EN4 (Enable Sensor 1-4). Same as EN0 for Voltage sensors 1-4.
0: Voltage Sensor disabled (default)
1: Voltage Sensor enabled
15-11 RO Reserved. Will always read "0".
2.11 CONVERSION RATE (Addr: 100 000; 20h)
Reg Add Register Name
R/
W
P
O
R
Val
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1
Bit 0
LSb
100 000 Conversion Rate
R/
W
2h
Reserved
CR1 CR0
0 0 0 0 0 0
Bit Type Description
1-0 RO CR0 and CR1 (Conversion Rate bits 0 and 1) These bits control the conversion rate of the LM40 for
more details see Table Conversion Rate Control and desciption below.
LM40
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