LPC47M192-NW Standard Microsystems (SMSC), LPC47M192-NW Datasheet - Page 133

• Manufacturer Part Number: LPC47M192-NW
• Manufacturer: Standard Microsystems (SMSC)

Specifications of LPC47M192-NW

• Lead Free Status / RoHS Status: Compliant

7.18.3.2.2
Setting bit 7 of the Configuration Register (0x40) performs a soft reset. This bit is self-clearing. Soft Reset performs
reset on all the registers except the Value and Limit Registers.
7.18.3.3
The RESET# function is multiplexed on A0/RESET#/THERM#/XNOR_OUT pin. Upon power up, the Hardware
Monitor Block reads this pin as an address pin (low bit of the SMBus address). The Hardware Monitor Block latches
the value of this pin as the low order bit of the SMBus address.
A reset pulse output function can be selected by writing a ‘1’ to bit 7 of the VID Register (0x47). If bit 4 (Reset) of
Configuration Register (0x40) is set, RESET# pin will output a minimum 20ms low pulse. The Reset bit is self-
clearing. The RESET# pin is open-drain and requires an external pullup resistor. If more than one Hardware Monitor
Block is used on a system, only one can have this function enabled at one time since this will limit the SMBus
address to 0101101, unless external circuitry is provided.
7.18.3.4
The Hardware Monitor Block supports two Monitoring modes: Continuous Mode and Cycle Mode. These modes are
selected using bit 1 of the Special Function Register (0x4F). The following subsections contain a description of these
monitoring modes.
For each mode, there are two options for the number of measurements that are performed on each temperature and
voltage reading. These options are selected using bit 5 of the special function register (0x4F). These options are as
follows:
1.
2.
For option 1, the block performs a total of (2 x 128) + (1 x 8) + (8 x 8) = 328 conversions. (8 less if the 12V input is not
selected i.e. 320).
Option 2 reduces the number of conversions to (2 x 16) + (1 x 1) + (8 x 1) = 41 (or 40 if the 12V input is not selected).
Each temperature conversion takes 1.688ms approx. and each voltage conversion takes 1.511ms approx.
The total time for option 1 (328 conversions) is (2x128x1.688ms) + (1x8x1.688ms) + (8x8x1.511ms) = 542.336ms.
The total time for option 2 (41 conversions) is (2x16x1.688ms) + (1x1x1.688ms) + (8x1x1.511ms) = 67.792ms.
7.18.3.4.1
In the continuous monitoring mode, the sampling and conversion process is performed continuously for each voltage
and temperature reading after the Start bit is set high. The time for each voltage and temperature reading is shown
above for each measurement option.
The continuous monitoring function is started by doing a write to the Configuration Register, setting the Start bit (Bit
0) high. The part then performs a “round robin” sampling of the inputs, in the order shown below (corresponding to
locations in the Value RAM). Sampling of all values occurs in 542.336 ms (or 67.792ms - see above).
SMSC DS – LPC47M192
128 measurements are averaged for the remote diode temperature reading and 8 measurements are averaged
for all voltage and the internal temperature reading. This is the default operation.
16 measurements are averaged for the remote diode temperature reading and a single measurement is taken for
all voltage and the internal temperature reading (i.e., no averaging). This is a power saving option.
Reset Out Pin
Monitoring Modes
Soft Reset
Continuous Monitoring Mode
DATASHEET
Page 133
Rev. 03/30/05