Photoflash Capacitor Charger with IGBT Driver and Refresh

A8439

4

Allegro MicroSystems, Inc.

115 Northeast Cutoff, Box 15036

Worcester, Massachusetts 01615-0036 (508) 853-5000

www.allegromicro.com

Characteristics

Symbol

Test Conditions

Min.

Typ. Max. Units

Supply Voltage*

3

–

5.5

V

Supply Current

Charging

–

1.5

–

mA

Charging done / Refresh monitoring

–

300

600

μA

–

0.01

1

μA

Primary Side Current Limit

(ILIM clock input at CHARGE pin)

1.2

1.4

1.6

A

–

1.2

–

A

–

1.0

–

A

–

0.86

–

A

–

0.7

–

A

–

0.55

–

A

–

0.4

–

A

–

0.27

–

A

SW On Resistance

–

0.27

–

Ω

SW Leakage Current*

–

–

1

μA

SW Maximum Off-Time

–18–

μs

SW Maximum On-Time

–18–

μs

CHARGE Input Current

––1

μA

CHARGE Input Voltage*

2––

V

–

–

0.8

V

ILIM Clock High Time at

CHARGE Pin

Initial pulse

20

–

–

μs

Subsequent pulses

0.2

–

–

μs

ILIM Clock Low Time at

CHARGE Pin

0.2

–

–

μs

Total ILIM Setup Time

–54–

μs

¯D¯¯O¯¯N¯¯E¯ Output Leakage Current*

––1

μA

¯D¯¯O¯¯N¯¯E¯ Output Low Voltage*

32 μA into ¯D¯¯O¯¯N¯¯E¯ pin

–

–

100

mV

FB Voltage Threshold*

1.187 1.205 1.223

V

FB Input Current

–

–120

–

nA

Auto-Refresh Threshold Level

–

1.07

–

V

UVLO Enable Threshold

2.55

2.65

2.75

V

UVLO Hysteresis

–

150

–

mV

IGBT Driver

IGBTDRV On Resistance to VIN

–5–

Ω

IGBTDRV On Resistance to GND

–

6

–

Ω

TRIGGER Input Current

––1

μA

TRIGGER Input Voltage*

2––

V

–

–

0.8

V

Propagation Delay, Rising

–

30

–

ns

Propagation Delay, Falling

–

30

–

ns

Output Rise Time

–

70

–

ns

Output Fall Time

–

70

–

ns

*Guaranteed by design and characterization over operating temperature range, –40°C to 85°C.