PMIC - Voltage Regulators

PMIC - Voltage Regulators - Linear

Part Number	Description / PDF	Quantity
AS1363-BSTT-33 ams	IC REG LINEAR 3.3V 500MA SOT23-6	0
AS1360-25-T ams	IC REG LINEAR 2.5V 125MA SOT23-3	2318
AS1358-BTTT-33 ams	IC REG LIN 3.3V 150MA TSOT23-5	2542
AS1353-18-T ams	IC REG LINEAR 1.8V 150MA SOT23-5	120
AS1359-BTTT-28 ams	IC REG LIN 2.8V 300MA TSOT23-5	623
AS1376-BTDT-12 ams	IC REG LINEAR 1.2V 1A 8TDFN	878
AS1376-BTDT-AD ams	IC REG LINEAR POS ADJ 1A 8TDFN	247
AS1351 ams	IC REG LINEAR 1.8V 200MA/12QFN	4258
AS1359-BTTT-31 ams	IC REG LIN 3.1V 300MA TSOT23-5	2
AS1352 ams	IC REG LINEAR 1.8V 200MA 12QFN	101
AS1375-BTDT-25 ams	IC REG LINEAR 2.5V 200MA 6TDFN	1002
AS1358-BTTT-28 ams	IC REG LIN 2.8V 150MA TSOT23-5	2249
AS1369-BWLT-13 ams	IC REG LINEAR 1.3V 200MA 4WLCSP	90
AS1358-BTTT-45 ams	IC REG LIN 4.5V 150MA TSOT23-5	2512
AS1369-BWLT-33 ams	IC REG LINEAR 3.3V 200MA 4WLCSP	150
AS1360-18-T ams	IC REG LINEAR 1.8V 110MA SOT23-3	413
AS1375 ams	IC REG LINEAR POS ADJ 200MA	0
AS1356-25-T ams	IC REG LINEAR 2.5V 150MA SOT23-5	0
AS1358-BTTT-18 ams	IC REG LIN 1.8V 150MA TSOT23-5	0
AS1363-BSTT-45 ams	IC REG LINEAR 4.5V 500MA SOT23-6	0

PMIC - Voltage Regulators - Linear

1. Overview

Linear Voltage Regulators (LVRs) are critical components in Power Management Integrated Circuits (PMICs) that provide stable output voltage levels by dissipating excess input energy as heat. Unlike switching regulators, LVRs operate without high-frequency switching, making them ideal for noise-sensitive applications. Their importance in modern electronics includes ensuring power integrity in portable devices, industrial equipment, and automotive systems.

2. Main Types and Functional Classification

Type	Functional Features	Application Examples
Low Dropout (LDO) Regulators	Maintain regulation with minimal input-output voltage differential (e.g., 100mV)	Mobile device sensors, RF circuits
Quasi-LDO Regulators	Balance dropout voltage and load current capability	Intermediate power stages in IoT devices
Dual/Multi-Output LVRs	Single-chip solutions with multiple regulated outputs	Application processors in smartwatches
High-Precision LVRs	0.5% output voltage accuracy with temperature compensation	Medical imaging sensors, test equipment

3. Structure and Components

Typical LVR architecture includes:

Reference Voltage Source (bandgap circuit)
Error Amplifier with feedback loop
Pass Transistor (NMOS/PMOS/BJT) as active regulation element
Thermal Shutdown and Overcurrent Protection Circuits
Input/Output Capacitor Interfaces

Common packages: QFN (3x3mm), TSSOP, WLCSP for portable devices. High-power variants use flip-chip with exposed thermal pads.

4. Key Technical Specifications

Parameter	Description	Importance
Input Voltage Range	Operational voltage limits (e.g., 2.7V-5.5V)	Determines compatibility with power sources
Output Voltage Accuracy	Deviation from nominal value ( 1% to 3%)	System stability and component protection
Dropout Voltage	Minimum Vin-Vout for regulation (e.g., 30mV-300mV)	Battery life optimization in portable devices
Output Current Capability	Max continuous load current (100mA-3A)	Application scalability
PSRR (Power Supply Rejection Ratio)	Noise attenuation at specific frequencies (e.g., 70dB at 1kHz)	Signal integrity in analog circuits
Quiescent Current	Standby power consumption (1 A-100 A)	Battery efficiency in always-on systems

5. Application Areas

Consumer Electronics: Smartphone APUs, SSD controllers
Industrial Automation: PLC signal conditioning modules
Automotive: ADAS sensors, infotainment system peripherals
Medical Devices: Portable diagnostic equipment, wearables
Telecommunications: Base station RF front-ends

6. Leading Manufacturers and Products

Manufacturer	Product Series	Key Features
Texas Instruments	TPS7A49	150mA, 18V input, 75dB PSRR @ 1kHz
STMicroelectronics	LDL1117	1A output, adjustable via resistor divider
Analog Devices	ADP151	200mA, 25 A quiescent current, 200mV dropout
ON Semiconductor	NCP1117	1A, thermal overload protection, automotive-grade

7. Selection Guidelines

Key selection criteria:

Match input voltage range with power source (e.g., Li-ion battery requires 2.7V-5.5V)
Prioritize low dropout voltage for battery-powered devices
Calculate thermal dissipation (PD = (Vin-Vout) Iout)
Select appropriate PSRR for noise-sensitive applications (e.g., 60dB for audio circuits)
Consider package thermal resistance for high-current applications

Case Study: A wearable ECG monitor used Analog Devices ADP150 (150mA, 2.2V output, 15 A IQ) to achieve 14-day battery life.

8. Industry Trends

Emerging Ultra-Low Dropout (ULDO) designs with <50mV dropout voltage
Integration with PMIC digital interfaces (I2C/PMBus)
Advanced packaging: 3D TSV for improved thermal performance
Wide bandgap (GaN/SiC) pass transistors for high-voltage LVRs
AEC-Q100 compliant automotive LVRs with 150 C operating temperature