AP2004

Features:

- PWM Buck Control Circuitry
- Operating voltage can be up to 27V
- Under voltage Lockout (UVLO) Protection
- Short Circuit Protection (SCP)
- Soft-start circuit
- Variable Oscillator Frequency -- 300Khz Max
- 1.25V voltage reference Output
- 8-pin PDIP and SOP packages




Application

- Backlight inverter
- LCD Monitor
- XDROM, XDSL Product
- DC/DC converters in computers, etc.




Specifications

Symbol	Parameter	Rating	Unit
VCC	Supply voltage	28	V
VI	Amplifier input voltage	20	V
VO	Collector output voltage	VCC-1.0V	V
ISOURCE	Source current	200	mA
ISINK	Sink current	200	mA
TOP	Operating temperature range	-20 to +85	oC
TST	Storage temperature range	-65 to +150	oC
TLEAD	Lead temperature 1.6 mm(1/16 inch) from case for 10 seconds	260	oC

Part Number	AP2004
Type	Buck
Min and Max Input Voltage (V)	3.6 ~ 27
Output Voltage (V)	1.25 to 25.5ADJ
Frequency (Hz)	300KADJ
Efficiency (%)	90

Description

The AP2004 integrates Pulse-Width-Modulation (PWM) control circuit into a single chip, mainly designs for power-supply regulator. All the functions include an on-chip 1.25V reference output, an error amplifier, an adjustable oscillator, a soft-start, UVLO, SCP circuitry, and a push-pull output circuit. Switching frequency is adjustable by trimming CT. During low VCC situation, the UVLO makes sure that the outputs are off until the internal circuit operates normally.