TPS56425

Part: TPS564255B (TPS56425xx family) — Texas Instruments

Type: Synchronous Buck Converter

Description: 3–17 V input, 4 A synchronous buck converter with integrated 55.0 mΩ / 24.3 mΩ MOSFETs, D-CAP3 control and 600 kHz switching in a 1.6 mm × 1.6 mm SOT-563 package; the TPS564255B variant uses Out-of-Audio (OOA) mode at light load.

Operating Conditions:

• Supply voltage (VIN): 3–17 V
• Operating junction temperature: -40 to 125 °C
• Output current: 0–4 A
• Output voltage range: 0.6–10 V

Absolute Maximum Ratings:

• Max VIN pin voltage: 18 V
• Max SW / BST pin voltage: 18 V (20 V transient < 20 ns)
• Max FB, EN pin voltage: 6 V
• Max operating junction temperature: 150 °C
• Storage temperature: -55 to 150 °C

Key Specs:

• Feedback reference voltage: 600 mV typ (594–606 mV at TJ = 25 °C; 591–609 mV at TJ = -40 to 125 °C)
• VIN supply current (no load, non-switching): 100 μA typ (ECO version); 370 μA typ (FCCM version)
• Shutdown current (VEN = 0 V): 2 μA typ
• High-side / low-side RDS(on) (TJ = 25 °C, VIN ≥ 5 V): 55.0 mΩ / 24.3 mΩ typ
• Switching frequency (TJ = 25 °C, VOUT = 3.3 V): 600 kHz typ (TPS564252B/5B/7B); 1.2 MHz typ (TPS564252C/7C)
• Valley overcurrent threshold: 4.1 / 5.5 / 6.7 A (min/typ/max)
• UVLO rising / falling threshold: 2.92 V / 2.72 V typ
• EN rising / falling threshold: 1.19 V / 1.00 V typ
• Soft-start time: 1.6 ms typ
• Minimum on / off time: 60 ns / 110 ns typ
• Thermal shutdown: 155 °C typ, 20 °C hysteresis

Features:

• D-CAP3 control mode with fast transient response and no external compensation
• Supports low-ESR and ceramic output capacitors
• ±1% reference accuracy at 25 °C; ±1.5% over -40 to 125 °C
• Integrated bootstrap capacitor for easy layout
• Start-up with prebiased output supported
• Maximum 97% duty cycle (B versions)
• Precision EN threshold
• OV, OT, UVLO protection (non-latch); hiccup UV protection; cycle-by-cycle OC and NOC protection
• Light-load modes: Eco-mode (252B/C), OOA (255B), FCCM (257B/C)

Applications:

• WLAN/Wi-Fi access point, switch, router
• Pro-audio, surveillance, drone
• TV, STB and DVR, smart speaker
• Solid state drive (SSD)
• Electricity meter

Package:

• DRL (SOT-563), 6 pins, 1.6 mm × 1.6 mm

• Configured for a wide range of applications
• -3V to 17V input voltage range
• -0.6V to 10V output voltage range
• -0.6V reference voltage
• -±1% reference accuracy at 25°C
• -±1.5% reference accuracy at -40°C to 125°C
• -Integrated 55.0mΩ and 24.3mΩ MOSFETs
• -100μA low quiescent current
• -600kHz switching frequency TPS564252B, TPS564255B, TPS564257B
• -1.2MHz switching frequency TPS564252C, TPS564257C
• -Maximum 97% large duty cycle operation for TPS564252B, TPS564255B, TPS564257B
• -Maximum 95% large duty cycle operation for TPS564252C, TPS564257C
• -Precision EN threshold voltage
• -1.6ms fixed typical soft-start time
• Ease of use and small design size
• -TPS564252B, TPS564252C Eco-mode, TPS564257B, TPS564257C FCCM mode, TPS564255B Out-of-Audio ™ (OOA) mode at light loading
• -D-CAP3 ™ control mode
• -Easy layout with integrated bootstrap capacitor
• -Supports start-up with prebiased output
• -Non-latch for OV, OT, and UVLO protection
• -Hiccup mode for UV protection
• -Cycle-by-cycle OC and NOC protection
• -1.6mm × 1.6mm SOT-563 package
• Create a custom design using the TPS56425xx with the WEBENCH ® Power Designer

• WLAN/Wi-Fi access point, switch, router
• Pro-audio, surveillance, drone
• TV, STB and DVR, smart speaker
• Solid state drive (SSD)
• Electricity meter

Simplified Application

Figure 4-1. 6-Pin SOT563 DRL Package (Top View)

Table 4-1. Pin Functions

TJ = -40°C to 125°C, VIN = 12V (unless otherwise noted)

over operating free-air temperature range (unless otherwise noted) (1)

Over operating free-air temperature range (unless otherwise noted)

The device is a typical buck DC/DC converter that is typically used to convert a higher DC voltage to a lower DC voltage with a maximum available output current of 4A. The following design procedure can be used to select component values for TPS56425xx. Alternately, the WEBENCH Power Designer software can be used to generate a complete design. The WEBENCH Power Designer software uses an iterative design procedure and accesses a comprehensive database of components when generating a design. This section presents a simplified discussion of the design process.