DCP3601

Part: DCP3601 — STMicroelectronics

Type: Synchronous Step-Down Converter

Description: A 3.3–36 V input, 1 A synchronous buck converter with 1 MHz fixed switching frequency, internal compensation, and peak current mode control, available in SOT23-6L package.

Operating Conditions:

• Supply voltage: 3.3–36 V
• Output current: 0–1 A
• Operating junction temperature: -40 to 150 °C

Absolute Maximum Ratings:

• Max supply voltage: 38 V
• Max continuous current: 1 A (output current)
• Max junction temperature: 150 °C
• Max storage temperature: -55 to 150 °C

Key Specs:

• Feedback voltage: 0.85 V (Typ. at Tj = 25 °C)
• Quiescent current (LCM version): 110 μA (Typ. at V EN = 3.3 V, V FB = 0.90 V, No Switching)
• Shutdown current: 4 μA (Typ. at V EN = 0 V)
• High-side MOSFET on-resistance: 0.5 Ω (Typ. at I SW = 0.1 A)
• Low-side MOSFET on-resistance: 0.26 Ω (Typ. at I SW = 0.1 A)
• High-side MOSFET switch current limit: 1.55 A (Typ. at V IN = 24 V)
• Switching frequency: 1 MHz (Typ.)
• Thermal shutdown threshold: 175 °C (Typ.)

Features:

• 1 MHz fixed switching frequency
• Synchronous rectification
• Internal compensation network
• Peak current mode control
• Two versions: LCM for high efficiency at light loads, LNM for noise-sensitive applications
• Output overvoltage protection
• Thermal shutdown
• Precision enable
• Switching frequency dithering

Applications:

• Major appliances
• Smart metering
• Industrial 24 V bus conversion

Package:

• SOT23-6L

• 88% typical efficiency at 600 mA load (V IN = 24 V, V OUT = 5 V)
• 91% typical efficiency at 600 mA load (V IN = 12 V, V OUT = 5 V)
• 3.3 V to 36 V input operating voltage range
• Up to 1 A output current capability
• 110 μA input quiescent current
• 1 MHz fixed switching frequency
• Synchronous rectification
• Internal compensation network
• Peak current mode control
• Two different versions: LCM for high efficiency at light loads and LNM for noise-sensitive applications
• Output overvoltage protection
• Thermal shutdown
• Precision enable
• Switching frequency dithering
• Available in SOT23-6L package

• Major appliances
• Smart metering
• Industrial 24 V bus conversion

TJ = 25 °C, V IN = 24 V unless otherwise specified.

Table 7. Electrical characteristics

Table 7. Electrical characteristics

Table 3. Absolute maximum ratings

Note: Absolute maximum ratings are those values beyond which damage to the device may occur. Functional operation under these conditions is not implied.

Table 4. Thermal data

Note: These values were calculated in accordance with JESD specification and simulated on a 4-layer JEDEC board.

Table 5. Recommended operating conditions

Table 6. ESD ratings

Table 6. ESD ratings

The shutdown block disables the switching activity if the junction temperature is higher than a fixed internal threshold (T SH , refer to Table 7). The thermal sensing element is close to the power elements, ensuring fast and accurate temperature detection. A hysteresis of approximately 20 °C prevents the device from turning ON and OFF too fast. After a thermal protection event has expired, the DCP3601 restarts with a new soft-start.

Table 1. Typical external components

Table 1. Typical external components

• VOUT L CIN (1) COUT (1) CBOOT (1) R1 R2
• 15 μH 2.2 μF / 50 V 22 μF / 25 V 100 μF / 50 V 73.2 kΩ 15 kΩ
• 5.0 V XGL5050-153 - Coilcraft 744393305150 - Wurth C2012X7R1H225K125AC - TDK C2012X5R1E226M125A - TDK C1608X7R1H104K080AA - TDK - -
• 10 μH 2.2 μF / 50 V 22 μF / 25 V 100 nF / 50 V 86.6 kΩ 30 kΩ
• 3.3 V XGL5050-103 - Coilcraft C2012X7R1H225K125AC - TDK C2012X5R1E226M125A - TDK C1608X7R1H104K080AA - TDK - -

To meet environmental requirements, ST offers these devices in different grades of ECOPACK packages, depending on their level of environmental compliance. ECOPACK specifications, grade definitions, and product status are available at: www.st.com. ECOPACK is an ST trademark.