Datasheet LTC3445 (Analog Devices) - 8

LTC3445
U U U PI FU CTIO S VTRACK (Pin 1):
Supply Sense that VCC BATT Tracks when
NC (Pin 13):
Not Connected. above 3V. Must be ≤ VCC1.
SW (Pin 14):
Buck Regulator Switch.
VBACKUP (Pin 2):
Back-Up Battery Input.
RUN (Pin 15):
Chip Enable. 1.5V enables the part. Forcing
VCC1 (Pins 3, 10):
Power Supply (2.5V to 5.5V). Both VCC1 this pin below 0.3V shuts down the device. In shutdown, pins must be connected externally to the 2.5V to 5.5V all functions are disabled, drawing <35µA supply current. supply. Do not leave RUN floating. Must be ≤ VCC1.
PGOOD (Pin 4):
Fault Report (Undervoltage). Open-drain
NC (Pin 16):
Not Connected. driver sinks current whenever LDO1, LDO2 or buck out-
FB (Pin 17):
Buck Regulator Feedback. puts are low.
V ADD7 (Pin 5):
I2C Strappable Address (Bit 7)—V
CC BATT (Pin 18):
VCC BATT PowerPath Output. CC1 or ground.
BATTFAULT (Pin 19):
Open-Drain Output. It is low when V
SDA (Pin 6):
I2C Data Input. CC1 is low.
LDO1FB (Pin 20):
LDO1 Regulator Sense.
NC (Pin 7):
Not Connected.
LDO1 (Pin 21):
LDO1 Regulator Output.
SCL (Pin 8):
I2C Clock Input.
V ADD6 (Pin 9):
I2C Strappable Address (Bit 6)—V
CC2 (Pin 22):
LDO Regulator Supply Voltage. CC1 or ground.
LDO2 (Pin 23):
LDO2 Regulator Output.
GND (Pin 11):
Buck NFET Ground.
LDO2FB (Pin 24):
LDO2 Regulator Sense.
NC (Pin 12):
Not Connected.
Exposed Pad (Pin 25):
Ground. Must be soldered to PCB ground for electrical contact and optimum thermal performance. 3445fa 8