4

AT9917

Sym

Parameter

Min

Typ

Max

Units Conditions

I

COMP

COMP sink current

#

0.2

-

-

mA

V

I

COMP

COMP source current

#

-0.2

-

-

mA

V

I

BIAS

Input bias current

#

-

0.5

1.0

nA

---

Oscillator

f

OSC1

Oscillator frequency

*

90

105

120

kHz

RT = 1.0MΩ

f

OSC2

Oscillator frequency

*

427

505

583

kHz

RT = 200kΩ

f

OSC

Output frequency range

#

100

-

800

kHz

---

Jitter

F

JTR

Jitter frequency

-

-

50

-

Hz

C

-

-

500

-

Hz

C

∆F

Change in the switching frequency

-

±4.5

-

-

kHz

---

Hiccup Timer

I

hiccup

Charging current

-

-

10

-

µA

---

∆V

Voltage swing for hiccup timer

-

-

0.6

-

V

---

Temperature Foldback Circuit

I

NTC

NTC current range

#

-

-

1.0

mA

---

N

NTC

I

-

-

0.13

-

-

I

N

T1

I

-

-

3.0

-

-

I

N

T2

I

-

-

6.0

-

-

I

V

T1 and T2 reference voltage

-

-

3.5

-

V

---

Output Short Circuit

G

FAULT

Amplifier gain at IREF pin

-

1.8

2.0

2.2

-

V

T

OFF

Propagation time for short circuit

detection

-

-

-

250

ns

V

FDBK steps from 0 - 1.0V;

FLT goes from high to low

T

RISE,FAULT

Fault output rise time

-

-

-

300

ns

330pF capacitor at FLT pin

T

FALL,FAULT

Fault output fall time

-

-

-

200

ns

330pF capacitor at FLT pin

V

MIN

Minimum voltage at the output of

the amplifier

#

250

-

-

mV

V

T

PWMD

PWMD Blanking time

*

200

-

900

ns

---

Soft Start

I

SS

Charging current

-

10

-

25

µA

---

I

SS

Discharging current

-

1.0

-

-

mA

V

V

SS

Reset voltage

-

-

-

100

mV

---

Slope Compensation

R

SLOPE

On-resistance of FET at CS pin

*

-

-

200

Ω

---

O

C. V

0.1μF, C

Notes:

* Specifications apply over the full operating ambient temperature range of -40ºC < T

# Specifications guaranteed by design and not tested in production