Datasheet LTC1775 (Analog Devices) - 3
| Hersteller | Analog Devices |
| Beschreibung | High Power No RSENSE Current Mode Synchronous Step-Down Switching Regulator |
| Seiten / Seite | 24 / 3 — ELECTRICAL CHARACTERISTICS The |
| Dateiformat / Größe | PDF / 307 Kb |
| Dokumentensprache | Englisch |
ELECTRICAL CHARACTERISTICS The
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LTC1775
ELECTRICAL CHARACTERISTICS The
●
denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25
°
C. VIN = 15V unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
TG Transition Time (Note 6) TG tR Rise Time CLOAD = 3300pF 50 150 ns TG tF Fall Time CLOAD = 3300pF 50 150 ns BG Transition Time (Note 6) BG tR Rise Time CLOAD = 3300pF 50 150 ns BG tF Fall Time CLOAD = 3300pF 50 150 ns
Internal VCC Regulator
VINTVCC Internal VCC Voltage 6V < VIN < 30V, VEXTVCC = 4V ● 5.0 5.2 5.4 V VLDOINT INTVCC Load Regulation ICC = 20mA, VEXTVCC = 4V – 0.2 – 1 % VLDOEXT EXTVCC Voltage Drop ICC = 20mA, VEXTVCC = 5V 180 300 mV VEXTVCC EXTVCC Switchover Voltage ICC = 20mA, VEXTVCC Ramping Positive ● 4.5 4.7 V
Oscillator
fOSC Oscillator Freqency SYNC = 0V 135 150 165 kHz fH/fOSC Maximum Synchronized Frequency Ratio 1.5 VSYNC SYNC Pin Threshold (Figure 4) Ramping Positive 0.9 1.2 V RSYNC SYNC Pin Input Resistance 50 kΩ
Note 1:
Absolute Maximum Ratings are those values beyond which the life
Note 4:
Typical in application circuit with EXTVCC tied to VOUT = 5V, of a device may be impaired. IOUT = 0A and FCB = INTVCC. Dynamic supply current is higher due
Note 2:
T to the gate charge being delivered at the switching frequency. See J is calculated from the ambient temperature TA and power dissipation P Applications Information. D according to the following formula: LTC1775CGN/LTC1775IGN: T
Note 5:
Minimum input supply voltage is 4.3V at – 40°C for industrial J = TA + (PD • 130°C/W) LTC1775CS/LTC1775IS: T grade parts. J = TA + (PD • 110°C/W)
Note 3:
The LTC1775 is tested in a feedback loop that adjusts V
Note 6:
Rise and fall times are measured at 10% to 90% levels. OSENSE to achieve a specified error amplifier output voltage (ITH). 3
ELECTRICAL CHARACTERISTICS The
●
denotes specifications which apply over the full operating temperature range, otherwise specifications are at TA = 25
°
C. VIN = 15V unless otherwise noted. SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
TG Transition Time (Note 6) TG tR Rise Time CLOAD = 3300pF 50 150 ns TG tF Fall Time CLOAD = 3300pF 50 150 ns BG Transition Time (Note 6) BG tR Rise Time CLOAD = 3300pF 50 150 ns BG tF Fall Time CLOAD = 3300pF 50 150 ns
Internal VCC Regulator
VINTVCC Internal VCC Voltage 6V < VIN < 30V, VEXTVCC = 4V ● 5.0 5.2 5.4 V VLDOINT INTVCC Load Regulation ICC = 20mA, VEXTVCC = 4V – 0.2 – 1 % VLDOEXT EXTVCC Voltage Drop ICC = 20mA, VEXTVCC = 5V 180 300 mV VEXTVCC EXTVCC Switchover Voltage ICC = 20mA, VEXTVCC Ramping Positive ● 4.5 4.7 V
Oscillator
fOSC Oscillator Freqency SYNC = 0V 135 150 165 kHz fH/fOSC Maximum Synchronized Frequency Ratio 1.5 VSYNC SYNC Pin Threshold (Figure 4) Ramping Positive 0.9 1.2 V RSYNC SYNC Pin Input Resistance 50 kΩ
Note 1:
Absolute Maximum Ratings are those values beyond which the life
Note 4:
Typical in application circuit with EXTVCC tied to VOUT = 5V, of a device may be impaired. IOUT = 0A and FCB = INTVCC. Dynamic supply current is higher due
Note 2:
T to the gate charge being delivered at the switching frequency. See J is calculated from the ambient temperature TA and power dissipation P Applications Information. D according to the following formula: LTC1775CGN/LTC1775IGN: T
Note 5:
Minimum input supply voltage is 4.3V at – 40°C for industrial J = TA + (PD • 130°C/W) LTC1775CS/LTC1775IS: T grade parts. J = TA + (PD • 110°C/W)
Note 3:
The LTC1775 is tested in a feedback loop that adjusts V
Note 6:
Rise and fall times are measured at 10% to 90% levels. OSENSE to achieve a specified error amplifier output voltage (ITH). 3