Datasheet LT8550 (Analog Devices) - 5
| Manufacturer | Analog Devices |
| Description | 4-Phase DC/DC Expander with Internal Gate Drivers for Buck Converters |
| Pages / Page | 34 / 5 — ELECTRICAL CHARACTERISTICS. The. denotes the specifications which apply … |
| File Format / Size | PDF / 3.2 Mb |
| Document Language | English |
ELECTRICAL CHARACTERISTICS. The. denotes the specifications which apply over the full operating
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LT8550
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = 12V, REG = 5V, VCC = 5V, SHDN = High, unless otherwise noted. PARAMETER CONDITIONS MIN TYP MAX UNITS Gate Drivers
TG1, TG2, TG3, TG4 Rise Time CLOAD = 3.3nF, SWx = 0V, BSTx = 5V (Note 4) 30 ns TG1, TG2, TG3, TG4 Fall Time CLOAD = 3.3nF, SWx = 0V, BSTx = 5V (Note 4) 20 ns BG1, BG2, BG3, BG4 Rise Time CLOAD = 3.3nF (Note 4) 50 ns BG1, BG2, BG3, BG4 Fall Time CLOAD = 3.3nF (Note 4) 27 ns Bottom & Top Gate Non-Overlap Time TG Falling to BG Rising, CLOAD = 3.3nF (Note 4) 85 ns BG Falling to TG Rising, CLOAD = 3.3nF (Note 4) 80 ns Bottom & Top Gate Minimum Off-Time CLOAD = 3.3nF (Note 4) 140 ns
Primary Gate Sensing
BGSH Rising Threshold l 4.0 V BGSH Falling Threshold l 1.0 V BGSH Threshold Hysteresis 1.4 V BGSH to BGBUF Delay CLOAD = 220pF, Master LT8550 (Note 4) 45 ns BGBUF Rise Time CLOAD = 220pF, Master LT8550 (Note 4) 8 ns BGBUF Fall Time CLOAD = 220pF, Master LT8550 (Note 4) 6 ns TGSH Rising Threshold TGSR = 5V, TGSL = 0V l 4.0 V TGSH Falling Threshold TGSR = 5V, TGSL = 0V l 1.0 V TGSH Threshold Hysteresis 1.4 V TGSH to TGBUF Delay CLOAD = 220pF, Master LT8550 (Note 4) 45 ns TGBUF Rise Time CLOAD = 220pF, Master LT8550 (Note 4) 8 ns TGBUF Fall Time CLOAD = 220pF, Master LT8550 (Note 4) 6 ns
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings characterization and correlation with statistical process controls. The may cause permanent damage to the device. Exposure to any Absolute LT8550I is guaranteed to meet performance specifications from –40°C to Maximum Rating Condition for extended periods may affect device 125°C junction temperature. reliability and lifetime.
Note 4:
Rise and fall times are measured using 10% and 90% levels. Delay
Note 2:
Do not apply a positive or negative voltage or current source times are measured using 50% levels. to REGDRV, BG1, BG2, BG3, BG4, TG1, TG2, TG3 and TG4, otherwise
Note 5:
Negative voltages on SW1/2/3/4 pins are limited, in an application, permanent damage may occur. by the body diodes of the external NMOS devices, or the parallel Schottky
Note 3:
The LT8550E is guaranteed to meet performance specifications diodes when present. The SW1/2/3/4 pins are tolerant of these negative from 0°C to 125°C junction temperature. Specifications over the –40°C voltages in excess of one diode drop below ground, guaranteed by design. to 125°C operating junction temperature range are assured by design, Rev. 0 For more information www.analog.com 5
ELECTRICAL CHARACTERISTICS The
l
denotes the specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25°C. VIN = 12V, REG = 5V, VCC = 5V, SHDN = High, unless otherwise noted. PARAMETER CONDITIONS MIN TYP MAX UNITS Gate Drivers
TG1, TG2, TG3, TG4 Rise Time CLOAD = 3.3nF, SWx = 0V, BSTx = 5V (Note 4) 30 ns TG1, TG2, TG3, TG4 Fall Time CLOAD = 3.3nF, SWx = 0V, BSTx = 5V (Note 4) 20 ns BG1, BG2, BG3, BG4 Rise Time CLOAD = 3.3nF (Note 4) 50 ns BG1, BG2, BG3, BG4 Fall Time CLOAD = 3.3nF (Note 4) 27 ns Bottom & Top Gate Non-Overlap Time TG Falling to BG Rising, CLOAD = 3.3nF (Note 4) 85 ns BG Falling to TG Rising, CLOAD = 3.3nF (Note 4) 80 ns Bottom & Top Gate Minimum Off-Time CLOAD = 3.3nF (Note 4) 140 ns
Primary Gate Sensing
BGSH Rising Threshold l 4.0 V BGSH Falling Threshold l 1.0 V BGSH Threshold Hysteresis 1.4 V BGSH to BGBUF Delay CLOAD = 220pF, Master LT8550 (Note 4) 45 ns BGBUF Rise Time CLOAD = 220pF, Master LT8550 (Note 4) 8 ns BGBUF Fall Time CLOAD = 220pF, Master LT8550 (Note 4) 6 ns TGSH Rising Threshold TGSR = 5V, TGSL = 0V l 4.0 V TGSH Falling Threshold TGSR = 5V, TGSL = 0V l 1.0 V TGSH Threshold Hysteresis 1.4 V TGSH to TGBUF Delay CLOAD = 220pF, Master LT8550 (Note 4) 45 ns TGBUF Rise Time CLOAD = 220pF, Master LT8550 (Note 4) 8 ns TGBUF Fall Time CLOAD = 220pF, Master LT8550 (Note 4) 6 ns
Note 1:
Stresses beyond those listed under Absolute Maximum Ratings characterization and correlation with statistical process controls. The may cause permanent damage to the device. Exposure to any Absolute LT8550I is guaranteed to meet performance specifications from –40°C to Maximum Rating Condition for extended periods may affect device 125°C junction temperature. reliability and lifetime.
Note 4:
Rise and fall times are measured using 10% and 90% levels. Delay
Note 2:
Do not apply a positive or negative voltage or current source times are measured using 50% levels. to REGDRV, BG1, BG2, BG3, BG4, TG1, TG2, TG3 and TG4, otherwise
Note 5:
Negative voltages on SW1/2/3/4 pins are limited, in an application, permanent damage may occur. by the body diodes of the external NMOS devices, or the parallel Schottky
Note 3:
The LT8550E is guaranteed to meet performance specifications diodes when present. The SW1/2/3/4 pins are tolerant of these negative from 0°C to 125°C junction temperature. Specifications over the –40°C voltages in excess of one diode drop below ground, guaranteed by design. to 125°C operating junction temperature range are assured by design, Rev. 0 For more information www.analog.com 5
