ISL88731CEVAL2Z Intersil, ISL88731CEVAL2Z Datasheet - Page 14

• Manufacturer Part Number: ISL88731CEVAL2Z
• Description: ISL88731C EVALUATION BOARD 2 - 28 Ld TQFN - COMPLI
• Manufacturer: Intersil
• Series: -r

Specifications of ISL88731CEVAL2Z

• Main Purpose: Power Management, Battery Charger
• Embedded: No
• Utilized Ic / Part: ISL88731C
• Primary Attributes: Li-Ion / Li-Pol, SMBus interface
• Secondary Attributes: -
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

The data (SDA) and clock (SCL) pins have Schmitt-trigger inputs
that can accommodate slow edges. Choose pull-up resistors for
SDA and SCL to achieve rise times according to the SMBus
specifications. The ISL88731C is controlled by the data written to
the registers described in Table 1.
Battery Charger Registers
The ISL88731C supports five battery-charger registers that use
either Write-Word or Read-Word protocols, as summarized in
Table 1. ManufacturerID and DeviceID are “read only” registers
and can be used to identify the ISL88731C. On the ISL88731C,
ManufacturerID always returns 0x0049 (ASCII code for “I” for
Intersil) and DeviceID always returns 0x0001.
Enabling and Disabling Charging
After applying power to ISL88731C, the internal registers contain
their POR values (see Table 1). The POR values for charge current
and charge voltage are 0x0000. These values disable charging.
To enable charging, the ChargeCurrent register must be written
with a number >0x007F and the ChargeVoltage register must be
written with a number >0x000F. Charging can be disabled by
writing 0x0000 to either of these registers.
BIT
10
11
12
13
14
15
0
1
2
3
4
5
6
7
8
9
Charge Voltage, DACV 0
Charge Voltage, DACV 1
Charge Voltage, DACV 2
Charge Voltage, DACV 3
Charge Voltage, DACV 4
Charge Voltage, DACV 5
Charge Voltage, DACV 6
Charge Voltage, DACV 7
Charge Voltage, DACV 8
Charge Voltage, DACV 9
Charge Voltage, DACV 10
BIT NAME
14
TABLE 2. CHARGEVOLTAGE (REGISTER 0x15)
Not used.
Not used.
Not used.
Not used.
0 = Adds 0mV of charger voltage, 1024mV min.
1 = Adds 16mV of charger voltage.
0 = Adds 0mV of charger voltage, 1024mV min.
1 = Adds 32mV of charger voltage.
0 = Adds 0mV of charger voltage, 1024mV min.
1 = Adds 64mV of charger voltage.
0 = Adds 0mV of charger voltage, 1024mV min.
1 = Adds 128mV of charger voltage.
0 = Adds 0mV of charger voltage, 1024mV min.
1 = Adds 256mV of charger voltage.
0 = Adds 0mV of charger voltage, 1024mV min.
1 = Adds 512mV of charger voltage.
0 = Adds 0mA of charger voltage.
1 = Adds 1024mV of charger voltage.
0 = Adds 0mV of charger voltage.
1 = Adds 2048mV of charger voltage.
0 = Adds 0mV of charger voltage.
1 = Adds 4096mV of charger voltage.
0 = Adds 0mV of charger voltage.
1 = Adds 8192mV of charger voltage.
0 = Adds 0mV of charger voltage.
1 = Adds 16384mV of charger voltage, 19200mV max.
Not used. Normally a 32768mV weight.
ISL88731C
Setting Charge Voltage
Charge voltage is set by writing a valid 16-bit number to the
ChargeVoltage register. This 16-bit number translates to a
65.535V full-scale voltage. The ISL88731C ignores the first 4
LSBs and uses the next 11 bits to set the voltage DAC. The
charge voltage range of the ISL88731C is 1.024V to 19.200V.
Numbers requesting charge voltage greater than 19.200V result
in a ChargeVoltage of 19.200V. All numbers requesting charge
voltage below 1.024V result in a voltage set point of zero, which
terminates charging. Upon initial power-up or reset, the
ChargeVoltage and ChargeCurrent registers are reset to 0 and
the charger remains shut down until valid numbers are sent to
the ChargeVoltage and ChargeCurrent registers. Use the Write-
Word protocol (Figure 21) to write to the ChargeVoltage register.
The register address for ChargeVoltage is 0x15. The 16-bit binary
number formed by D15–D0 represents the charge voltage set
point in mV. However, the resolution of the ISL88731C is 16mV
because the D0–D3 bits are ignored as shown in Table 2. The
D15 bit is also ignored because it is not needed to span the
1.024V to 19.2V range. Table 2 shows the mapping between the
charge-voltage set point and the 16-bit number written to the
ChargeVoltage register. The ChargeVoltage register can be read
back to verify its contents.
DESCRIPTION
February 8, 2011
FN6978.2