ispPAC-POWR6AT6-01SN32I Lattice, ispPAC-POWR6AT6-01SN32I Datasheet - Page 14

• Manufacturer Part Number: ispPAC-POWR6AT6-01SN32I
• Description: Supervisory Circuits Prec Prog Pwr Supply Seq Mon Trim IND
• Manufacturer: Lattice
• Series: ispPAC®r

Specifications of ispPAC-POWR6AT6-01SN32I

• Number Of Voltages Monitored: 6
• Monitored Voltage: Adjustable
• Undervoltage Threshold: Adjustable
• Overvoltage Threshold: Adjustable
• Manual Reset: Not Resettable
• Watchdog: No Watchdog
• Supply Voltage (max): 3.96 V
• Supply Voltage (min): 2.8 V
• Supply Current (typ): 10000 uA
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: QFNS-32
• Minimum Operating Temperature: - 40 C
• Applications: Power Supply Controller/Monitor
• Voltage - Input: -0.3 V ~ 5.9 V
• Voltage - Supply: 2.8 V ~ 3.96 V
• Current - Supply: 10mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: *
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

Lattice Semiconductor
Table 3-1. TrimCell Voltage Profile and Operating Modes
TrimCell Operation in Voltage Profiles 1, 2 and 3: The output trimming voltage is determined by the code stored
in the DAC Registers 1, 2, and 3 corresponding to the selected Voltage Profile.
TrimCell Operation in Voltage Profile 0: The Voltage Profile 0 has three operating modes. They are DAC Register
0 Select mode, DAC Register I
E
during Voltage Profile 0 mode of operation.
DAC Register 0 Select Mode: The contents of DAC register 0 are stored in the on-chip E
Voltage Profile 0 is selected, the DAC will be loaded with the value stored in DAC Register 0.
DAC Register I
microcontroller to control the DC-DC converter output voltage. The microcontroller updates the contents of the DAC
Register I
is reset to 80H (DAC at Bipolar zero) upon power-on. The external microcontroller writes the correct DAC code in
this DAC Register I
Digital Closed Loop Trim Mode
Closed loop trim mode operation can be used when tight control over the DC-DC converter output voltage at a
desired value is required. The closed loop trim mechanism operates by comparing the measured output voltage of
the DC-DC converter with the internally stored voltage setpoint. The difference between the setpoint and the actual
DC-DC converter voltage generates an error voltage. This error voltage adjusts the DC-DC converter output volt-
age toward the setpoint. This operation iterates until the setpoint and the DC-DC converter voltage are equal.
Figure 3-10 shows the closed loop trim operation of a TrimCell. At regular intervals (as determined by the Update
Rate Control register) the ispPAC-POWR6AT6 device initiates the closed loop power supply voltage correction
cycle through the following blocks:
2
CMOS configuration memory. Each of the six TrimCells can be independently set to different operating modes
VPS[1:0]
• Non-volatile Setpoint register stores the desired output voltage
• On-chip ADC is used to measure the voltage of the DC-DC converter
• Three-state comparator is used to compare the measured voltage from the ADC with the Setpoint regis-
• Channel polarity control determines the polarity of the error signal
• Closed loop trim register is used to compute and store the DAC code corresponding to the error voltage.
• The DAC in the TrimCell is used to generate the analog error voltage that adjusts the attached DC-DC con-
ter contents. The output of the three state comparator can be one of the following:
The contents of the Closed Loop Trim will be incremented or decremented depending on the channel polar-
ity and the three-state comparator output. If the three-state comparator output is 0, the closed loop trim reg-
ister contents are left unchanged.
verter output voltage.
11
10
01
00
2
C on the fly to set the trimming voltage to a desired value. The DAC Register I
• +1 if the setpoint voltage is greater than the DC-DC converter voltage
• -1 if the setpoint voltage is less than the DC-DC converter voltage
• 0 if the setpoint voltage is equal to the DC-DC converter voltage
2
C Select Mode: This mode is used if the power management arrangement requires an external
Voltage Profile 3
Voltage Profile 2
Voltage Profile 1
Voltage Profile 0
2
C before enabling the programmable power supply.
Selected Voltage Profile
2
C Select mode and Closed Loop Trim mode. The mode selection is stored in the
Digital Closed Loop Trim
DAC Register I
DAC Register 0 Select
3-14
Selected Mode
—
—
—
2
C Select
ispPAC-POWR6AT6 Data Sheet
DAC Register 3 (E
DAC Register 2 (E
DAC Register 1 (E
DAC Register 0 (E
Closed Loop Trim Register
DAC Register (I
Trimming Voltage
2
is Controlled by
C is a volatile register and
2
CMOS memory. When
2
2
2
2
CMOS)
CMOS)
CMOS)
CMOS)
2
C)