LMR51410YFDBVR

Part: LMR51410XDBVR — Texas Instruments

Type: Synchronous Buck Converter

Description: 4–42 V input, 1 A synchronous buck converter with 400 kHz fixed switching frequency (PFM variant), adjustable output of 0.8–28 V, integrated FETs and internal compensation in a SOT-23-6 package.

Operating Conditions:

• Supply voltage (VIN to GND): 4–42 V
• Operating junction temperature: -40 to 150 °C
• Output voltage range: 0.8–28 V
• Output current: up to 1 A (LMR51410)

Absolute Maximum Ratings:

• Max input voltage (VIN to GND): 45 V
• SW to GND: 45 V (50 V for transients under 10 ns)
• Max junction temperature: 150 °C
• Storage temperature: -55 to 150 °C

Key Specs:

• Reference voltage (VFB): 0.8 V typ (0.788–0.812 V over TJ -40 to 150 °C)
• Quiescent current (non-switching, PFM variant, VEN = 3 V): 26.5 μA typ, 40 μA max
• Shutdown supply current (VEN = 0 V): 0.8 μA typ, 3 μA max
• Switching frequency ("X" version, CCM): 400 kHz typ (340–460 kHz)
• High-side RDS(on): 0.7 Ω typ; low-side RDS(on): 0.36 Ω typ (VIN = 12 V, TJ = 25 °C)
• High-side peak current limit (LMR51410): 1.6 A typ (1.25–1.95 A)
• Low-side valley current limit (LMR51410): 1.1 A typ (0.9–1.3 A)
• VIN UVLO rising threshold: 3.82 V typ, 4 V max; falling threshold: 3.56 V typ
• Minimum on-time: 80 ns typ (VIN = 12 V, IOUT = 0.1 A); soft-start time: 2.3 ms typ
• Thermal shutdown: 165 °C typ with 20 °C hysteresis

Features:

• Functional Safety-Capable, with documentation available
• Input transient protection up to 50 V
• 98% maximum duty cycle
• Monotonic start-up with prebiased output
• Hiccup-mode short-circuit protection and cycle-by-cycle current limit
• Precision enable with adjustable UVLO
• ±1.5% reference voltage tolerance
• Integrated synchronous rectification and internal compensation
• PFM and forced PWM (FPWM) options
• Pin-to-pin compatible with LMR51610, LMR16006, LV2862, LMR50410, TPS560430 and LMR54410

Applications:

• Major appliances
• PLC, DCS, and PAC
• Smart meters
• Power delivery

Package:

• DBV (SOT-23, 6 pins), 2.90 mm × 2.80 mm

• Functional Safety-Capable
• -Documentation available to aid functional safety system design
• Configured for rugged industrial applications
• -4V to 42V input voltage range
• -Input transient protection up to 50V
• -0.6A / 1A continuous output current
• -80ns minimum switching on time
• -Fixed 400kHz and 1.1MHz switching frequency
• --40°C to 150°C junction temperature range
• -98% maximum duty cycle
• -Monotonic start-up with prebiased output
• -Short-circuit protection with hiccup mode
• -Precision enable
• -±1.5% tolerance voltage reference
• Small design size and ease of use
• -Integrated synchronous rectification
• -Internal compensation for ease of use
• -SOT-23 package
• Various options in pin-to-pin compatible package -PFM and forced PWM (FPWM) options
• Pin-to-pin compatible with the LMR51610, LMR16006, LV2862, LMR50410, TPS560430 and LMR54410
• Create a custom design using the LMR514xx with the WEBENCH ® Power Designer

• Major appliances
• PLC, DCS, and PAC
• Smart meters
• Power delivery

Simplified Schematic

Figure 5-1. 6-Pin SOT-23 DBV Package (Top View)

Table 5-1. Pin Functions

• (1) A = Analog, P = Power, G = Ground

Limits apply over operating junction temperature (T J ) range of -40°C to +150°C, unless otherwise stated. Minimum and Maximum limits (1) are specified through test, design or statistical correlation. Typical values represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless otherwise stated, the following conditions apply: VIN = 4V to 42V.

Over junction temperature range of -40°C to 150°C (unless otherwise noted) (1)

Over the recommended operating junction temperature range of -40°C to 150°C (unless otherwise noted) (1)

The value of RθJA given in this table is only valid for comparison with other packages and cannot be used for design purposes. These values were calculated in accordance with JESD 51-7, and simulated on a 4-layer JEDEC board. They do not represent the performance obtained in an actual application. For example, with a 2-layer PCB, a R θJA = 95 °C /W can be achieved. For design information, see Maximum Output Current Versus Ambient Temperature.

The LMR514xx is a step-down DC-to-DC converter. The LMR51410 is typically used to convert a higher input voltage to a lower output DC voltage with a maximum output current of 1A. The LMR51406 is typically used to convert a higher input voltage to a lower output DC voltage with a maximum output current of 0.6A. The following design procedure can be used to select components for the LMR514xx.