HT77XX

PFM Asynchronous Step-up DC to DC Converter (100mA)

Selection Table

Part No.

Output Voltage

Package

Marking

HT7718

1.8V

TO92

SOT89

SOT23

SOT23-5

HT77XX (for TO92)

HT77XX# (for SOT89)

HT77XX+ (for SOT89)

77XX# (for SOT23)

77XX+ (for SOT23)

77XX# (for SOT23-5)

77XX+ (for SOT23-5)

HT7722

2.2V

HT7727

2.7V

HT7730

3.0V

HT7733

3.3V

HT7737

3.7V

HT7750

5.0V

Note:

²XX² stands for output voltages.

Both lead free and green compound devices are available.

²#² stands for lead free devices. For the TO-92 package, there will be a ²#² mark at the end of the date code.

²+² stands for green compound devices, which are Lead-free and Halogen-free.

For the TO-92 package, there will be a

²+² mark at the end of the date code.

Rev 1.90

1

October 13, 2010

Features

5.0V

Applications

General Description

The HT77XX series is a set of PFM step-up DC/DC con-

verter with high efficiency and low ripple. The series fea-

tures extremely low start-up voltage and high output

voltage accuracy. They require only three external com-

ponents to provide a fixed output voltage of 1.8V, 2.2V,

2.7V, 3.0V, 3.3V, 3.7V or 5.0V. CMOS technology en-

sures ultra low supply current and makes them ideal for

battery-operated applications powered from one or

more cells.

The HT77XX consists of an oscillator, a PFM control cir-

cuit, a driver transistor, a reference voltage unit, and a

high speed comparator. They employ pulse frequency

modulation (PFM) for minimum supply current and rip-

ple at light output loading. These devices are available

in space saving TO92, SOT89, SOT23 and SOT23-5

packages. For SOT23-5 package, it also build-in a chip

enable function to reduce power consumption during

shutdown mode.