LTC7813 datasheet(5/36 Pages) LINER

5 / 36 page

LTC7821

Rev A

For more information www.analog.com

ELECTRICAL CHARACTERISTICS The

denotes the specifications which apply over the specified operating

junction temperature range, otherwise specifications are at TA = 25°C (Note 2). VIN = VIN_SENSE = 48V, VRUN = 5V, EXTVCC = 9V,

EXT_REF = 5.6V unless otherwise noted.

SYMBOL

PARAMETER

CONDITIONS

MIN

TYP

MAX

UNITS

IFLYSRC1

Current Out of SW1 During Capacitor

Balancing

(VSW1 – VSW3) < VIN/2, VSW3 = 12V

IFLYSNK1

Current into SW1 During Capacitor Balancing (VSW1 – VSW3) > VIN/2, VSW3 = 12V

IFLYSNK3

Current into SW3 During Capacitor Balancing (VSW1 – VSW3) < VIN/2, VSW3 = 12V

IFLYSRC3

Current Out of SW3 During Capacitor

Balancing

(VSW1 – VSW3) < VIN/2, VSW3 = 12V

IMID_SRC

Current Out of MID During Capacitor

Balancing

VMID < VIN/2, VMID = VMID_SENSE = 20V

VSW1 ≥ 36V, VSW3 = 12V

IMID_SNK

Current into MID During Capacitor Balancing VMID > VIN/2, VMID = VMID_SENSE = 28V

VSW1 ≥ 36V, VSW3 = 12V

Gate Driver

TG1,2

Pull-Up ON Resistance

Pull-Down ON Resistance

BG1, 2

Pull-Up ON Resistance

Pull-Down ON Resistance

TG1,2 tr

TG1,2 tf

TG1, TG2 Transition Time:

Rise Time

Fall Time

(Note 7)

BG1,2 tr

BG1,2 tf

BG1, BG2 Transition Time:

Rise Time

Fall Time

(Note 7)

T1D

TG1 Off to BG1 On

T2D

TG2 Off to BG2 On

T3D

TG1 Off to TG2 Off

T4D

BG1 Off to TG1 On

T5D

BG2 Off to TG2 On

T6D

BG1 Off to BG2 Off

ton(MIN)

Minimum On-Time

(Note 8)

210

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: The LTC7821E 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 LTC7821I is guaranteed

to meet performance specifications over the full –40°C to 125°C operating

junction temperature range. 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.

Note 3: TJ is calculated from the ambient temperature TA and power

dissipation PD according to the following formulas:

LTC7821UH: TJ = TA + (PD • 44°C/W)

Note 4: Output voltage range is guaranteed by design. For output voltage

setting, read “Output Voltage Setting” and “Minimum VOUT” in the

“Applications Information” section.

Note 5: The LTC7821 is tested in a feedback loop that servos VITH to a

specified voltage and measures the resultant VFB.

Note 6: Dynamic supply current is higher due to the gate charge being

delivered at the switching frequency. See Applications Information.

Note 7: Rise and fall times are measured using 10% and 90% levels. Delay

times are measured using 50% levels.

Note 8: 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 9: This IC includes overtemperature protection that is intended

to protect the device during momentary overload conditions. Junction

temperature will exceed 125°C when overtemperature protection is active.

Continuous operation above the specified maximum junction temperature

may impair device reliability or permanently damage the device.

LTC7813 датащи(PDF) 5 Page - Linear Technology

LTC7813 датащи(HTML) 5 Page - Linear Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

датащи скачать

ссылки URL