LTC3670

3

3670f

Note 1: Stresses beyond those listed under Absolute Maximum Ratings

may cause permanent damage to the device. Exposure to any Absolute

Maximum Rating condition for extended periods may affect device

reliability and lifetime.

Note 2: This IC includes overtemperature protection that is intended

to protect the device during momentary overload conditions. Junction

temperatures will exceed 125°C when overtemperature protection is

active. Continuous operation above the specified maximum operating

junction temperature may result in device degradation or failure.

Note 3: The LTC3670 is guaranteed to meet performance specifications

from 0°C to 85°C. Specifications over the –40°C to 85°C operating

temperature range are assured by design, characterization and correlation

with statistical process controls.

Note 4: Dynamic supply current is higher due to the gate charge delivered

to the buck regulator’s internal MOSFET switches at the switching

frequency.

SYMBOL

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

Synchronous Buck Regulator

Oscillator Frequency

1.91

2.25

2.59

MHz

Buck Regulated Feedback Voltage

l

0.78

0.8

0.82

V

Feedback Pin Input Bias Current

l

±20

nA

PMOS Switch Maximum Peak Current (Note 6)

600

800

1100

mA

PMOS Switch On-Resistance

0.6

Ω

NMOS Switch On-Resistance

0.7

Ω

SW Pin Pull-Down Resistance in Shutdown

10

kΩ

Soft-Start Time

0.6

ms

Each LDO Regulator

LDO Regulated Feedback Voltage

l

0.78

0.8

0.82

V

LDO Line Regulation (Note 7)

0.25

mV/V

LDO Load Regulation (Note 7)

–5

μV/mA

Feedback Pin Input Bias Current

l

±20

nA

Short-Circuit Output Current (Note 6)

420

mA

Dropout Voltage (Note 8)

150

200

200

300

mV

mV

Soft-Start Time

0.1

ms

Output Pull-Down Resistance in Shutdown

10

kΩ

Note 5: PGOOD threshold is expressed as a percentage of the feedback

regulation voltage. The threshold is measured for the feedback pin voltage

rising.

Note 6: The current limit features are intended to protect the IC from

short term or intermittent fault conditions. Prolonged operation above

the specified Absolute Maximum pin current rating may result in device

degradation or failure.

Note 7: Measured with the LDO running unity gain, with output tied to

feedback pin.

Note 8: Dropout voltage is the minimum input to output voltage differential

needed for an LDO to maintain regulation at a specified output current.

When an LDO is in dropout, its output voltage will be equal to: