Ultra Small Mobile Phone Xenon Photoflash

Capacitor Charger with IGBT Driver

5

Allegro MicroSystems, Inc.

115 Northeast Cutoff

Worcester, Massachusetts 01615-0036 U.S.A.

1.508.853.5000; www.allegromicro.com

A8732

Switch On-Resistance

–

0.4

–

Ω

Switch Leakage Current

(note 1)

–

–

2

μA

CHARGE Pull-down Resistance

–

100

–

kΩ

CHARGE Input Voltage

High, over input supply range (note 1)

1.0

–

–

V

Low, over input supply range (note 1)

–

–

0.4

V

Charge Pin Programming

ILIM Programming High at CHARGE Pin

Initial Pulse (note 3)

15

–

–

μs

Subsequent Pulses (note 3)

0.2

–

–

μs

ILIM Programming Low at CHARGE Pin

(note 3)

0.2

–

–

μs

Total ILIM Setup Time at CHARGE Pin

(note 3)

–

200

–

μs

Switch-Off Timeout

–

18

–

μs

Switch-On Timeout

–

18

–

μs

Output Comparator Trip Voltage

31

31.5

32

V

Output Comparator Voltage Overdrive

Pulse width = 200 ns (90% to 90%)

–

200

400

mV

¯D¯¯O¯¯N¯¯E¯ Leakage Current

(note 1)

1

μA

¯D¯¯O¯¯N¯¯E¯ Output Low Voltage

32 μA into ¯D¯¯O¯¯N¯¯E¯ pin (note 1)

–

–

100

mV

dV/dt Threshold for ZVS Comparator

dV/dt

Measured at SW pin

–

20

–

V/μs

IGBT Driver

TRIG Input Voltage

Input = logic high, over input supply range

(note 1)

1.0

–

–

V

Input = logic low, over input supply range

(note 1)

–

–

0.4

V

TRIG Pull-Down Resistor

–

100

–

kΩ

GATE Resistance to VIN_DRV

–

21

–

Ω

GATE Resistance to GND

–

27

–

Ω

Propagation Delay (Rising)

Measurement taken at GATE pin,

–

25

–

ns

Propagation Delay (Falling)

(notes 3, 5)

–

60

–

ns

Output Rise Time

(notes 3, 5)

–

290

–

ns

Output Fall Time

(notes 3, 5)

–

380

–

ns

GATE Pull-Down Resistor

–

20

–

kΩ

indicates

specifications guaranteed from −40°C to 85°C ambient, unless otherwise noted