The AX2596 is Monolithic IC that design for a step-down DC/DC Converter, and own the ability of driving a 3A load without additional transistor component. The output version included 3.3V, 5V, 12V and an adjustable type. It 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. 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.

Features:
· 3.3V, 5V, 12V and adjustable
· Adjustable version output voltage range: 1.3-37V
· ± 4% max. over line and load conditions
· 150KHz ± 15% fixed switching frequency
· TTL shutdown capability
· Operating voltage can be up to 40V
· Output load current: 3A
· TO220-5L and TO263-5L packages
· Low power standby mode
· Thermal-shuntdown and current-limit protection
· High efficiency
· Built-in switching a transistor on chip, requires only 4 external components

Applications :
· Simple High-efficiency step-down regulator
· Positive to negative converter
· On-card switching regulators

Package: TO-220-5L, TO-263-5L

Part No.

Parameter

Symbol

Conditions

Min.

Typ.

Max.

Unit

AX2596-3.3

Output Voltage

V_OUT

4.75V£V_IN£40V, 0.2A£I_LOAD£3A

3.168  3.135

3.3

3.342 3.465

V

Efficiency

h

V_IN=12V, I_LOAD=3A

-

73

-

%

AX2596-5.0

Output Voltage

V_OUT

7V£V_IN£40V, 0.2A£I_LOAD£3A

4.800  4.750

5.0

5.200  5.250

V

Efficiency

h

V_IN=12V, I_LOAD=3A

-

80

-

%

AX2596-12

Output Voltage

V_OUT

15V£V_IN£40V, 0.2A£I_LOAD£3A

11.52  11.40

12.0

12.48  12.60

V

Efficiency

h

V_IN=25V, I_LOAD=3A

-

90

-

%

AX2596-ADJ

Output Voltage

V_OUT

4.5V£V_IN£40V, 0.2A£I_LOAD£3A        V_OUT programmed for 3V

1.193  1.180

1.230

1.267  1.280

V

Efficiency

h

V_IN=12V, V_OUT=3V, I_LOAD=3A

-

73

-

%

All Output Voltage Versions Electrical Characteristics
Specifications with boldface type apply over for full operating temperature range, the other type are for T J =25 ℃
(Unless otherwise specified, V IN =12V for the 3.3V, 5V, and adjustable version and V IN =24V for the 12V version, I LOAD =500mA )

Oscillator Frequency

f_O

The switching frequency is reduced when the second stage current limit is activated.

127       110

150

173    173

KHz

Saturation Voltage

V_SAT

I_OUT=3A

No diode, inductor or capacitor connected to output pin.

Feedback pin removed from output and connected to 0V to force the output transistor switch ON.

-

1.3

1.4    1.5

V

Max. Duty Cycle (ON)

Min. Duty Cycle (OFF)

DC

Feedback pin removed from output and connected to 0V to force the output transistor switch ON.

Feedback pin removed from output and connected to 12V for the 3.3V, 5V, ADJ. version, and 15V for the 12V version, to force the output transistor switch OFF.

-

100

0

-

%