MIC284 Micrel Semiconductor, MIC284 Datasheet - Page 6

• Manufacturer Part Number: MIC284
• Description: Two-Zone Thermal Supervisor Advance Information
• Manufacturer: Micrel Semiconductor

MIC284
Functional Diagram
FUNCTIONAL DESCRIPTION
Pin Descriptions
VDD: Power supply input. See electrical specifications.
GND: Ground return for all MIC284 functions.
CLK: Clock input to the MIC284 from the two-wire serial bus.
The clock signal is provided by the host, and is shared by all
devices on the bus.
DATA: Serial data I/O pin that connects to the two-wire serial
bus. DATA is bi-directional and has an open-drain output
driver. An external pull-up resistor or current source some-
where in the system is necessary on this line. This line is
shared by all devices on the bus.
A0: This inputs sets the least significant bit of the MIC284’s
7-bit slave address. The six most-significant bits are fixed
and are determined by the part number ordered. (See order-
ing information table above.) Each MIC284 will only respond
to its own unique slave address, allowing up to eight MIC284s
to share a single bus. A match between the MIC284’s
address and the address specified in the serial bit stream
must be made to initiate communication. A0 should be tied
directly to VDD or ground. See "Temperature Measurement
MIC284
DATA
CLK
A0
T1
MIC284
Reference
Serial Bus
Bandgap
Interface
Register
Sensor
Pointer
2-Wire
MUX
and
2:1
1-Bit
DAC
∑
T_SET & /CRIT
Configuration
Temperature
Hysteresis
Registers
Registers
Registers
Setpoint
Register
Result
GND
VDD
6
and Power On" for more information. A0 determines the slave
address as shown in Table 1:
/INT: Temperature events are indicated to external circuitry
via this output. Operation of the /INT output is controlled by
the MODE and IM bits in the MIC284’s configuration register.
See "Comparator and Interrupt Modes" below. This output is
open-drain and may be wire-OR’ed with other open-drain
signals. Most systems will require a pull-up resistor or current
source on this pin. If the IM bit in the configuration register is
∫
P
a
M
M
M
M
t r
C I
C I
C I
C I
N
2
2
2
2
u
8
8
8
8
Table 1. MIC284 Slave Address Settings
m
4
4
4
4
0 -
2 -
3 -
1 -
b
TEMPERATURE-TO-DIGITAL
r e
Open-Drain
Output
Digital Filter
Comparator
Machine
Control
Digital
Logic
State
n I
and
and
CONVERTER
A
p
0
0
0
0
1
1
1
1
u
0
s t
/INT
/CRIT
1
1
1
1
1
1
1
1
M
0
0
0
0
0
0
0
0
B
0
0
0
0
0
0
0
0
C I
n i
1
1
1
1
1
1
1
1
2
a
0
0
0
0
1
1
1
1
8
y r
0
0
1
1
0
0
1
1
4
0
1
0
1
0
1
0
1
September 29, 2000
b
b
b
b
b
b
b
b
S
a l
v
e
A
d
d
e r
H
4
4
4
4
4
4
4
4
s
C
D
e
A
B
E
F
8
9
s
x
h
h
h
h
h
h
h
h
Micrel