Overview
The SG3525AN, produced by STMicroelectronics, is a pulse width modulator (PWM) integrated circuit designed to enhance performance and reduce the external parts count in various switching power supply designs. This device is part of the SG3525A series, which offers a range of features that make it versatile and efficient for power management applications.
Key Specifications
| Parameter | Value | Unit |
|---|---|---|
| Supply Voltage (VCC) | 8.0 to 35 | V |
| Collector Supply Voltage (VC) | 8.0 to 35 | V |
| Reference Output Voltage (Vref) | 5.1 ± 1.0% | V |
| Oscillator Frequency Range | 100 Hz to 400 kHz | |
| Output Current, Source or Sink (IO) | ±500 mA | |
| Reference Output Current (Iref) | 50 mA | |
| Oscillator Charging Current | 5.0 mA | |
| Power Dissipation (PD) at TA = +25°C | 1000 mW | |
| Junction Temperature Range (Tj) | -55 to 150°C | |
| Storage Temperature Range (Tstg) | -65 to 150°C |
Key Features
- Dual Source/Sink Output Drivers: Capable of sourcing or sinking in excess of 200 mA.
- Latching PWM: Prevents multiple pulses by keeping the outputs off for the duration of the period after a PWM pulse is terminated.
- Pulse-by-Pulse Shutdown: Allows for instantaneous turn-off through the PWM latch with pulsed shutdown and soft-start recycle with longer shutdown commands.
- Internal Soft-Start: Requires only an external timing capacitor.
- 8.0 V to 35 V Operation: Wide operating voltage range.
- 100 Hz to 400 kHz Oscillator Range: Adjustable oscillator frequency.
- 5.1 V Reference Trimmed to ±1%: High accuracy reference voltage.
- Adjustable Deadtime Control: Adjustable deadtime using a single resistor.
- Input Undervoltage Lockout with Hysteresis: Prevents operation below nominal input voltage with approximately 500 mV of hysteresis.
- Separate Oscillator Sync Terminal: Allows synchronization with an external system clock.
Applications
The SG3525AN is widely used in various switching power supply designs, including:
- Switch-mode power supplies (SMPS)
- DC-DC converters
- Power inverters
- Motor control systems
- High-frequency power supplies
Q & A
- What is the operating voltage range of the SG3525AN?
The SG3525AN operates within a voltage range of 8.0 V to 35 V.
- What is the accuracy of the on-chip reference voltage?
The on-chip reference voltage is trimmed to ±1% at 5.1 V.
- What is the oscillator frequency range of the SG3525AN?
The oscillator frequency range is from 100 Hz to 400 kHz.
- How does the SG3525AN handle deadtime adjustment?
Deadtime can be adjusted using a single resistor connected between the CT and Discharge pins.
- What is the purpose of the undervoltage lockout feature?
The undervoltage lockout feature keeps the outputs off and the soft-start capacitor discharged for sub-normal input voltages, ensuring jitter-free operation.
- Can the SG3525AN be synchronized with an external clock?
Yes, the SG3525AN has a separate oscillator sync terminal that allows synchronization with an external system clock.
- What type of output drivers does the SG3525AN have?
The SG3525AN features dual source/sink output drivers capable of sourcing or sinking in excess of 200 mA.
- How does the soft-start feature work in the SG3525AN?
The SG3525AN has built-in soft-start circuitry that requires only an external timing capacitor for operation.
- What is the maximum output current of the SG3525AN?
The maximum output current is ±500 mA.
- What is the junction temperature range of the SG3525AN?
The junction temperature range is from -55°C to 150°C.
