HT77XX
PFM Asynchronous Step-up DC to DC Converter (100mA)
Features
·
Low start-up voltage: 0.7V (Typ.), 0.9V (Max.)
·
High efficiency: 85% (Typ.), V
OUT
³2.7V
·
High output voltage accuracy:
±2.5%
·
Output voltage: 1.8V, 2.2V, 2.7V, 3.0V, 3.3V, 3.7V,
·
Output current up to 100mA
·
Ultra low supply current I
DD2
: 4mA (Typ.)
·
Low ripple and low noise
·
Low shutdown current: 0.5mA (Typ.)
·
TO92, SOT89, SOT23 and SOT23-5 package
5.0V
Applications
·
Palmtops/PDAs
·
Portable communicators/Smartphones
·
Cameras/Camcorders
·
Battery-powered equipment
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.
Selection Table
Part No.
HT7718
HT7722
HT7727
HT7730
HT7733
HT7737
HT7750
Note:
Output Voltage
1.8V
2.2V
2.7V
3.0V
3.3V
3.7V
5.0V
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)
Package
Marking
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
HOLTEK [ HOLTEK SEMICONDUCTOR INC ]
