150kHz, 2A PWM Buck DC/DC Converter

TJ1509A

FEATURES

●

Output voltage: 3.3V, 5V, 12V and adjustable

output version

●

Adjustable version output voltage range,

1.23V to 18V+4%

●

150KHz +15% fixed switching frequency

●

Voltage mode non-synchronous PWM control

●

Thermal-shutdown and current-limit protection

●

ON/OFF shutdown control input

●

Operating voltage can be up to 26V

●

Output load current: 2A

●

SOP-8L packages

●

Low power standby mode

●

Built-in switching transistor on chip

●

Moisture Sensitivity Level 3

APPLICATIONS

●

Simple High-efficiency step-down regulator

●

On-card switching regulators

●

Positive to negative converter

●

Negative Step-Up Converters

ORDERING INFORMATION

●

Power Supply for Battery Chargers

DESCRIPTION

Mar. 2010 - R1.3

HTC

TJ1509A 5.0

SOP-8

PIN DESCRIPTION

4

Pin No

Function

Description

1

Vin

Operating voltage input

5~8

TJ1509AD-ADJ

TJ1509A ADJ

TJ1509AD-3.3

TJ1509A 3.3

TJ1509AD-12

TJ1509A 12

TJ1509AD-5.0

- 1 -

2

Vout

Switching output

3

FB

Output voltage feedback control

SD

ON/OFF Shutdown

Ground

Ground

Device

Marking

Package

The TJ1509A series are monolithic IC designed for a step-down DC/DC converter, and own the ability of

driving a 2A load without additional transistor component. Due to reducing the number of external

component, the board space can be saved easily. The external shutdown function can be controlled by

logic level and then come into standby mode.

The internal compensation makes feedback control have good line and load regulation without external

design. Regarding protected function, thermal shutdown is to prevent over temperature operating from

damage, and current limit is against over current operating of the output switch. If current limit function

occurred and VFB is down to 0.5V below, the switching frequency will be reduced.

The TJ1509A series operates at a switching frequency of 150KHz thus allowing smaller sized filter

components than what would be needed with lower frequency switching regulators. Other features

include a guaranteed +4% tolerance on output voltage under specified input voltage and output load

conditions, and +15% on the oscillator frequency.

The output version included fixed 3.3V, 5V, 12V, and an adjustable type.

The packages are available in a standard 8-lead SOP-8 package.

SOP-8 PKG