A voltage regulator is an integrated circuit that is used to maintain a stable output voltage instead of changing the input voltage (or) load conditions. Almost every electronic device is designed with a voltage regulator to keep the load voltage stable. Generally, a voltage regulator may utilize a simple feed-forward design (or) may contain negative feedback, an electromechanical mechanism (or) electronic components. It is used to adjust one (or) more AC or DC voltages based on the design. There are different voltage regulators are available from different semiconductor manufacturers like; L4940V5, LM340T5, LM2940S,7805, XC6206, LT1085, AZ1084, BA3258HFP, LP2985, AP2112, etc. This article elaborates on AZ1084 IC, pinout, specifications, and uses.
What is AZ1084 IC?
AZ1084 is a positive LDO voltage regulator, available in standard packages like TO-263-2, TO263, TO-220-3, TO-252-2, TO-252-2 & TO-252-2. This voltage regulator’s low dropout voltage is 1.5V at 5Amps of load current, current limiting circuit, on-chip thermal limiting & a trimmed band-gap reference. This low dropout positive voltage regulator is available in various versions: 1.5Volts, 1.8Volts, 2.5Volts, 3.3Volts, & 5.0Volts versions.
This voltage regulator is also available in an adjustable version that can set the output voltage through two external resistors while fixed version regulators have incorporated adjusted resistors. The AZ1084 voltage regulator is well-matched with power supplies, battery chargers, DC to DC single output power supplies, desktop PCs, linear regulators, desktop processors, post-regulators, microprocessor power supplies, etc.
How AZ1084 IC Work?
The AZ1084 low dropout positive voltage regulator IC works by providing a stable output voltage apart from changes in input voltage (or) load. This IC is available in two versions fixed & adjustable. So fixed version voltage regulators have integrated adjust resistors whereas the adjustable version regulators can set the output voltage through two external resistors. This IC provides thermal shutdown & current limit functions to guarantee the stability of the chip & power system. The AZ1084 IC has a current limiting circuit to guard against extreme junction temperatures and also has a trimmed band-gap reference.
AZ1084 IC Pin Configuration:
The AZ1084 IC pin configuration is shown below. So this IC includes three pins which are discussed below.
AZ1084 IC Pin Configuration
- Pin-1 (ADJ/GND): It is an adjustable or GND pin of IC that adjusts the output version whereas GND is for fixed type version
- Pin-2 (OUTPUT): It is an output pin of a voltage regulator IC.
- Pin-3 (INPUT): It is an input voltage pin of IC.
Features & Specifications:
The features and specifications of AZ1084 IC include the following.
- AZ1084 IC is a Low Dropout linear voltage regulator IC.
- It is available in different packages like; TO263, TO-220-3, TO263-2, TO-252-2, TO-252-2 & TO-252-2.
- Its typical low dropout voltage is 1.35V at 5A.
- The output current is 5A.
- Its current limit is 6.5A.
- Its typical line regulation is 0.015% and load regulation is 0.1%.
- This IC is RoHS and Lead-free compliant.
- It is antimony and halogen-free.
- It is compatible with a low ESR ceramic capacitor.
- PSRR is 72dB at 120Hz.
- The operating junction temperature ranges from 0 to +125°C.
Equivalents & Alternatives
Equivalent AZ1084 ICs are; LT1085, AZ1084CD-5.0TRG, AZ2185D-ADJTRG1, AZ1084CD-3.3TRG1, etc. Alternate LDO regulators are; LM1084, LT3094, LT1085, LDO40L, SGM2019-ADJYN5G/TR, LM317D2T, TPS76350DBVR, etc.
AZ1084 Voltage Regulator Circuit
The AZ1084 voltage regulator IC is very simple to use because it needs the highest number of components. This IC has a similar pin-out as LM1084. In addition, AZ1084 IC is available in three variants where one is an adjustable regulator & two types include fixed regulated output. In the following circuit, the AZ1084 IC is in an adjustable mode where its regulated output voltage can be changed by modifying the R1 & R2 resistor values. So in the fixed type Az1084 regulator type, the ADJ pin can be changed by the GND pin.
AZ1084 Voltage Regulator Circuit
In the above circuit, a 10uF tan capacitor is connected as a bypass capacitor in between the input & GND. Similarly, a 22uF tan capacitor is connected between the output & GND.
The ripple rejection can be improved by using a CAdj bypass capacitor between the adjust terminal & GND improves ripple rejection. Here, the bypass capacitor prevents ripple rejection from being changed when the output voltage is enhanced.
So the CAdj impedance must be below the R1 resistance to avoid ripple from being changed at any frequency. Whenever the R1 resistor value is usually in the 120Ω to 200Ω range then the CAdj value must satisfy the below condition.
1/(2π* FrequencyRipple *Cadj)<R1
The adjustable regulator version’s output voltage satisfies the below equation:
Vout = VRef * (1+R2/R1)+IAdj×R2.
Here, the IAdj×R2 term can be ignored since the IAdj (~ 50µA) adjustable pin current is below the current throughout R1 (~ 4mA). The R1 resistor value is preferred in the range of 120Ω～200Ω. The whole output current of the adjustable version of needs to go beyond 10mA to assure usual chip operation.
Advantages & Disadvantages
The advantages of AZ1084 IC include the following.
- AZ1084 voltage regulator IC at a high current value has a low voltage drop.
- This IC has on-chip thermal limiting that gives protection from any overload & ambient temperatures combination that creates extreme junction temperatures.
- It has low power consumption, high efficiency, etc.
- It is available in compact & space-saving designs.
- This IC has robust protection features which ensure reliable operation.
- It is simple to use and simplifies power supply design greatly.
- It is less costly due to mass production.
- These are versatile, so used conveniently for local regulation.
- It has built-in protection, current/voltage boosting, programmable output, internal short circuit current limiting, and many more.
The disadvantages of AZ1084 IC include the following.
- These regulators have a higher ground-pin current as compared to quasi-LDOs or standard regulators.
- LDO regulators can dissipate more power if these ICs have a higher current (or) a huge variation between the I/O voltages.
- The highest input voltage can be lower as compared to standard regulators.
- Some LDO regulators need specially selected external capacitors to maintain stability.
- Whenever these regulator ICs are designed to block reverse current, the dropout voltage will be double. So to decrease this, the MOSFETs size has to be increased which can make the total solution larger.
- The GND pin current of this regulator is generally higher as compared to a quasi-LDO (or) a standard regulator.
Applications
The applications of AZ1084 IC include the following.
- The AZ1084 LDO regulator is used in battery chargers, microprocessor supplies, desktop processors, linear regulators, post-Regulators, etc.
- These regulators are used in desktop PCs, embedded processors’ supplies, RISC, high-efficiency linear regulators, embedded processors’ supply, etc.
- These are used in microprocessor power supply, post-regulation for switching supplies, high-efficiency linear regulators, etc.
Please refer to this link for the AZ1084 IC Datasheet.
Thus, this is brief information about AZ1084 positive voltage regulator IC which has a low voltage drop at a higher current value. So, the highest voltage drop by this IC is 1.3V at 5A of load current. AZ1084 IC comes with an integrated Zener diode mainly for thermal shutdown and current limiting purposes. So this voltage regulator is available in TO263-2, TO263, TO-220-3, TO-252-2, TO-252-2 & TO-252-2 Packages. The regulated output voltage of this voltage regulator can be adjusted with two resistors. Here is a question for you, what is LM1084 IC?