ISL78229 Datasheet, PDF (42/71 Pages) Intersil Corporation – 2-Phase Boost Controller with Drivers

ISL78229
Device Identification Address and
Read/Write
The ISL78229 serves as a slave device on the PMBus™. The 7-bit
physical slave address can be set by the ADDR1 and ADDR2 pin
configurations to have 4 address options. Table 5 defines the 4
available 7-bit addresses for the ISL78229 where the bits [7:3]
are fixed and bits [2:1] are determined by the ADDR1 and ADDR2
pin configurations. Bit [0] is R/W bit to define the command to
perform Read (Bit = 1) or Write (Bit = 0).
TABLE 5. SLAVE ADDRESS SET BY THE ADDR1 AND ADDR2 PIN
CONFIGURATIONS
ADDR1/ADDR2
SETTING
DEVICE IDENTIFICATION -SLAVE
ADDRESS
BITS 7-1
R/W
BIT
BIT 0
ADDR1 ADDR2
BIT FIELD
7654321 0
GND
GND 1 0 0 1 1 0 0 Write: 0
Read: 1
GND
VCC 1 0 0 1 1 1 0 Write: 0
Read: 1
VCC
GND 1 0 0 1 1 0 1 Write: 0
Read: 1
VCC
VCC 1 0 0 1 1 1 1 Write: 0
Read: 1
PMBus™ Data Formats Used in ISL78229
The data format used in the ISL78229 are listed below.
16-BIT LINEAR UNSIGNED (16LU)
16-bit Linear Unsigned (16Lu) data format is a two byte (16-bit)
unsigned binary integer. For ISL78229, the 16Lu data format is
used to:
Read the 16Lu Data to Report the 10-Bit ADC Input Voltage
The 16Lu data format is used in some commands to report the
binary unsigned integer data at the 10-bit ADC output, where the
Bits [15:10] are not used and Bits [9:0] are used and equals to
the 10-bit ADC output unsigned binary integer value. The input of
the ADC is alternatively connected to voltages of NTC, FB, VIN/48
and IMON pins for monitoring.
The ADC has 2mV for 1 LSB. So the 16Lu data can report voltage
range of 0V to 2.046V (2mV*(2^10-1)).
Equation 21 can be used to convert the 16Lu data reported by
the commands to ADC input voltage, where COMMAND is the
10-bit [9:0] unsigned binary integer value:
V_ADCIN = 0.002  COMMAND
(EQ. 21)
Write/Read the 16Lu Data as the 8-Bit DAC Input
The 16Lu data format is used in command “VOUT_COMMAND
(21h)” on page 48 to set or read the 8-bit DAC input binary
unsigned integer data which changes the DAC output voltage.
The DAC output voltage is VREF_DAC, which is the reference to
the output voltage regulation. In this command, the 8-bit [7:0]
unsigned binary integer value are used and equal to the 8-bit
DAC output binary integer value.
The DAC has 8mV for 1 LSB. So the 16Lu data can set VREF_DAC
voltage range of 0V to 2.04V (8mV*(2^8-1)).
Equation 22 can be used to convert the 16Lu data written/read
by the VOUT_COMMAND to DAC output voltage, where
COMMAND is the 8-bit [7:0] unsigned binary integer value in the
command:
V_DACOUT = 0.008  COMMAND= V_REFDAC
(EQ. 22)
Write/Read the 16Lu Data to Set NTC Threshold
The 16Lu data format is used in command
“OT_NTC_FAULT_LIMIT (4Fh)” on page 50 and
“OT_NTC_WARN_LIMIT (51h)” on page 51 to set the
OT_NTC_WARN and OT_NTC_FAULT thresholds. The 10-bit [9:0]
unsigned binary integer values are used and the 1 LSB
represents 2mV.
Equation 23 can be used to convert the 16Lu data in the
OT_NTC_FAULT_LIMIT and OT_NTC_WARN_LIMIT commands to
the voltage thresholds for the NTC pin, where COMMAND is the
10-bit [9:0] unsigned binary integer value in the command:
V_OTNTC = 0.002  COMMAND
(EQ. 23)
BIT FIELD (BIT)
Breakdown of Bit Field is provided in “PMBus™ Command Detail”
starting on page 46.
CUSTOM (CUS)
Breakdown of Custom data format is provided in “PMBus™
Command Detail” starting on page 46. A combination of Bit Field
and integer are common type of Custom data format.
The 10-bit ADC accuracy from output to input has typical
tolerances of -15mV to +25mV over the ADC input range of 0V to
2.046V.
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FN8656.3
February 12, 2016