Thermal Information

Symbol

Parameter

Package

Max.

Unit

Thermal Resistance

(Junction to Ambient)

(Assume no ambient airflow,

no heat sink)

SOT89

300

°C/W

TO92

300

°C/W

SOT23

330

°C/W

SOT23-5

320

°C/W

Power Dissipation

SOT89

0.33

W

TO92

0.33

W

SOT23

0.3

W

SOT23-5

0.31

W

°C

Electrical Characteristics

Symbol

Parameter

Test Conditions

Min.

Typ.

Max.

Unit

Input Voltage

¾¾

¾

6V

Output Voltage Tolerance

¾-2.5

¾

2.5

%

Start-up Voltage (Fig. 1)

¾

0.7

0.9

V

¾¾

0.7

V

No-load Input Current (Fig. 1)

¾

10

20

mA

Supply Current 1 (Fig. 2)

´0.95

¾

35

50

mA

¾

37

55

¾

40

60

¾

45

68

¾

55

81

¾

64

85

¾

85

134

Supply Current 2 (Fig. 2)

¾

47

mA

Shutdown Current

CE=GND

¾

0.5

1

mA

CE High Threshold

¾

2

¾¾

V

CE Low Threshold

¾¾

¾

0.4

V

LX Leakage Current (Fig. 3)

Measured at the LX pin

¾¾

0.9

mA

Maximum Oscillator Frequency

(Fig. 3)

´0.95

Measured at LX pin

¾

115

¾

kHz

Oscillator Duty Cycle (Fig. 3)

´0.95

Measured at LX pin

65

75

85

%

h

Efficiency

£2.2V

¾

80

¾

%

³2.7V

¾

85

¾

Note:

Absolute maximum ratings indicate limits beyond which damage to the device may occur. Operating Ratings

indicate conditions for which the device is intended to be functional, but do not guarantee specific performance

limits. The guaranteed specifications apply only for the test conditions listed.

HT77XX

Rev 1.90

3

October 13, 2010