MIC384 Datasheet, PDF (6/21 Pages) Micrel Semiconductor – Three-Zone Thermal Supervisor Advance Information

MIC384
Functional Diagram
T1
T2
VDD
3:1
MUX
∑
∫
Bandgap
Sensor
and
Reference
1-Bit
DAC
8-Bit Sigma-Delta ADC
Digital Filter
and
Control
Logic
Micrel
A0
DATA
CLK
2-Wire
Serial Bus
Interface
Pointer
Register
MIC384
Result
Registers
Temperature
Setpoint
Registers
Temperature
Hysteresis
Registers
Configuration
Register
GND
State
Machine
and
Digital
Comparator
Open-Drain
Output
/INT
Functional Description
Pin Descriptions
VDD: Power supply input. See electrical specifications.
GND: Ground return for all MIC384 functions.
CLK: Clock input to the MIC384 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 MIC384’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 MIC384 will only respond
to its own unique slave address, allowing up to eight MIC384’s
to share a single bus. A match between the MIC384’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
and Power On" for more information. A0 determines the slave
address as shown in Table 1:
Part Number
Inputs
A0
MIC384 Slave Address
Binary
Hex
MIC384-0
0
100 1000_b
48_h
1
100 1001_b
49_h
MIC384-1
0
100 1010_b
4A_h
1
100 1011_b
4B_h
MIC384-2
0
100 1100_b
4C_h
1
100 1101_b
4D_h
MIC384-3
0
100 1110_b
4E_h
1
100 1111_b
4F_h
Table 1. MIC384 Slave Address Settings
/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 MIC384’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
MIC384
6
September 2000