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LTC7813

7813f

For more information www.linear.com/LTC7813

elecTrical characTerisTics The

denotes the specifications which apply over the specified operating

junction temperature range, otherwise specifications are at TA = 25°C. (Note 2) VBIAS = 12V, VRUN1,2 = 5V, VEXTVCC = 0V, VDRVSET = 0V,

VPRG2 = 0V unless otherwise noted.

SYMBOL

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

Oscillator and Phase-Locked Loop

Programmable Frequency

RFREQ =25kΩ, PLLIN/MODE = DC Voltage

105

kHz

Programmable Frequency

RFREQ = 65kΩ, PLLIN/MODE = DC Voltage

375

440

505

kHz

Programmable Frequency

RFREQ = 105kΩ, PLLIN/MODE = DC Voltage

835

kHz

Low Fixed Frequency

VFREQ = 0V, PLLIN/MODE = DC Voltage

320

350

380

kHz

High Fixed Frequency

VFREQ = INTVCC, PLLIN/MODE = DC Voltage

485

535

585

kHz

Synchronizable Frequency

PLLIN/MODE = External Clock

850

kHz

PLLIN VIH

PLLIN VIL

PLLIN/MODE Input High Level

PLLIN/MODE Input Low Level

PLLIN/MODE = External Clock

2.5

0.5

BOOST2 Charge Pump

BOOST2 Charge Pump Available Output

Current

FREQ = 0V, PLLIN/MODE = INTVCC

VBOOST2 = 16.5V, VSW2 = 12V

VBOOST2 = 19V, VSW2 = 12V

µA

Note 1: Stresses beyond those listed under Absolute Maximum Ratings

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

Maximum Ratings for extended periods may affect device reliability and

lifetime.

Note 2: The LTC7813 is tested under pulsed load conditions such that

TJ ≈ TA. The LTC7813E is guaranteed to meet performance specifications

from 0°C to 85°C. Specifications over the –40°C to 125°C operating

junction temperature range are assured by design, characterization and

correlation with statistical process controls. The LTC7813I is guaranteed

over the –40°C to 125°C operating junction temperature range, the

LTC7813H is guaranteed over the –40°C to 150°C operating junction

temperature range and the LTC7813MP is tested and guaranteed over

the –55°C to 150°C operating junction temperature range. High junction

temperatures degrade operating lifetimes; operating lifetime is derated

for junction temperatures greater than 125°C. Note that the maximum

ambient temperature consistent with these specifications is determined by

specific operating conditions in conjunction with board layout, the rated

package thermal impedance and other environmental factors. The junction

temperature (TJ, in °C) is calculated from the ambient temperature

(TA, in °C) and power dissipation (PD, in Watts) according to the formula:

TJ = TA + (PD • θJA)

where θJA = 44°C.

Note 3: This IC includes overtemperature protection that is intended to

protect the device during momentary overload conditions. The maximum

rated junction temperature will be exceeded when this protection is active.

Continuous operation above the specified absolute maximum operating

junction temperature may impair device reliability or permanently damage

the device.

Note 4: The LTC7813 is tested in a feedback loop that servos VITH1,2 to a

specified voltage and measures the resultant VFB1,2. The specification at

85°C is not tested in production and is assured by design, characterization

and correlation to production testing at other temperatures (125°C for

the LTC7813E and LTC7813I, 150°C for the LTC7813H and LTC7813MP).

For the LTC7813I and LTC7813H, the specification at 0°C is not tested in

production and is assured by design, characterization and correlation to

production testing at –40°C. For the LTC7813MP, the specification at 0°C

is not tested in production and is assured by design, characterization and

correlation to production testing at –55°C.

Note 5: Dynamic supply current is higher due to the gate charge being

delivered at the switching frequency. See Applications information.

Note 6: Rise and fall times are measured using 10% and 90% levels. Delay

times are measured using 50% levels

Note 7: The minimum on-time condition is specified for an inductor

peak-to-peak ripple current >40% of IMAX (See Minimum On-Time

Considerations in the Applications Information section).

Note 8: Do not apply a voltage or current source to these pins. They must

be connected to capacitive loads only, otherwise permanent damage may

occur.

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