LTC2970IUFD Datasheet, PDF (1/36 Pages) Linear Technology – Dual I2C Power Supply Monitor and

FEATURES
■ _{Less Than ±0.5% Total Unadjusted Error 14-Bit ΔΣ}
ADC with On-Chip Reference
■ _{Dual, 8-Bit IDACs with 1x Voltage Buffers}
■ _{Linear, Voltage Servo Adjusts Supply Voltages by}
Ramping IDAC Outputs Up/Down
■ _I²_{C™ Bus Interface (SMBus Compatible)}
■ _{Extensive, User Configurable Fault Monitoring}
■ _{On-Chip Temperature Sensor}
■ _{Available in 24-Lead 4mm × 5mm QFN Package}
U
APPLICATIO S
■ _{Dual Power Supply Voltage Servo}
■ _{Monitoring Supply Voltage and Current}
■ _{Programmable Power Supplies}
■ _{Programmable Reference}
LTC2970/LTC2970-1
Dual I²C Power
Supply Monitor and
Margining Controller
DESCRIPTIO
The LTC^®2970 is a dual power supply monitor and
margining controller with an SMBus compatible I²C bus
interface. A low-drift, on-chip reference and 14-bit ΔΣ A/D
converter allow precise measurements of supply voltages,
load currents or internal die temperature. Fault manage-
ment allows ^⎯A^⎯L^⎯E^⎯R^⎯T to be asserted for configurable over
and under voltage fault conditions. Two voltage buffered,
8-bit IDACs allow highly accurate programming of DC/DC
converter output voltages. The IDACs can be configured
to automatically servo the power supplies to the desired
voltages using the ADC. The LTC2970-1 adds a tracking
feature that can be used to turn multiple power supplies
on or off in a controlled manner.
The bus address is set to 1 of 9 possible combinations by
pin strapping the ASEL0 and ASEL1 pins. The LTC2970/
LTC2970-1 are packaged in the 24-lead, 4mm × 5mm
QFN package.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
TYPICAL APPLICATIO
Dual Power Supply Monitor and Controller (One of Two Channels Shown)
8V TO 15V
V_IN IN
OUT
I+
I–
DC/DC
CONVERTER
12V_IN
V_DD
1/2 LTC2970
V_{IN0_BM}
V_{IN0_BP}
V_OUT0
V_{IN0_AP}
GPIO_CFG
ALERT
SCL
SDA
0.1μF
0.1μF
I²C BUS
( ) ^SMBUS
COMPATIBLE
RUN/SS FB
LOAD
I_OUT0
GPIO_0
GND ^SGND
V_{IN0_AM}
REF
GND ASEL0 ASEL1
0.1μF
ADC Total Unadjusted Error
vs Temperature
0.50 _{15 PARTS MOUNTED ON PCB}
0.25
0
–0.25
–0.50
–50 –25 0
ADC V_IN = 5V
25 50 75 100
TEMPERATURE (°C)
29701 TA01b
29701 TA01
29701fc
1