LMR50410

Part: LMR50410XFDBVR (LMR50410 family) — Texas Instruments

Type: Synchronous Buck Converter (FPWM variant)

Description: 4–36 V input, 1 A synchronous buck converter with 700 kHz fixed switching frequency, adjustable output (1 V reference, ±1%), internal compensation and a SOT-23-6 package.

Operating Conditions:

• Supply voltage: 4–36 V
• Operating junction temperature: -40 to 150 °C
• Output voltage range: 1–28 V; output current 0–1 A
• Switching frequency: 700 kHz (600–800 kHz over temperature)

Absolute Maximum Ratings:

• Max VIN to GND: 38 V
• Max EN to GND: VIN + 0.3 V
• Max SW to GND: VIN + 0.3 V (38 V for transients under 10 ns)
• Max FB to GND: 5.5 V
• Max CB to SW: 5.5 V
• Max junction temperature: 150 °C
• Storage temperature: -65 to 150 °C

Key Specs:

• Feedback voltage VFB: 0.99 / 1 / 1.01 V (min/typ/max)
• VIN UVLO: rising 3.55–4 V (3.75 V typ); falling 3.25–3.65 V (3.45 V typ); 0.3 V hysteresis
• Shutdown quiescent current (VEN = 0 V): 3 μA typ, 10 μA max
• Enable thresholds: rising 1.23 V typ, falling 1.1 V typ, 130 mV hysteresis
• High-side current limit (VIN = 12 V): 1.25–1.9 V... 1.25 to 1.9 A (1.6 A typ); low-side limit 0.9–1.3 A (1.1 A typ)
• Negative current limit (FPWM): -0.6 A typ
• RDS(on) at TJ = 25 °C, VIN = 12 V: high-side 450 mΩ, low-side 240 mΩ
• Minimum on-time 60 ns typ; minimum off-time 110 ns typ; maximum duty cycle 98%
• Soft-start 1.8 ms typ; hiccup interval 135 ms typ; thermal shutdown 170 °C rising, 158 °C falling
• Output regulation in FPWM: -1.5% to +1.5%

Features:

• Functional Safety-Capable; documentation available
• Precision enable allowing adjustable UVLO
• Integrated synchronous rectification
• Internal compensation and soft-start
• Monotonic start-up with pre-biased output
• Cycle-by-cycle current limit, hiccup-mode short-circuit protection and thermal shutdown
• FPWM operation for constant frequency and low output ripple across full load range (PFM option also available as LMR50410X)
• Pin-to-pin compatible with LMR14010A and TPS560430
• WEBENCH Power Designer support

Applications:

• Major appliances
• PLC, DCS, and PAC
• Smart meters
• General purpose wide-VIN power supplies

Package:

• SOT-23-6 (DBV), 2.90 mm × 1.60 mm nominal body

• Functional Safety-Capable
• -Documentation available to aid functional safety system design
• Configured for rugged industrial applications
• -Input voltage range: 4 V to 36 V
• -1-A continuous output current
• -Minimum switching-on time: 60 ns
• -700-kHz fixed switching frequency
• -Junction temperature range: -40°C to 150°C
• -98% maximum duty cycle
• -Monotonic start-up with pre-biased output
• -Internal short circuit protection with hiccup mode
• -±1% tolerance voltage reference
• -Precision enable
• Small solution size and ease of use
• -Integrated synchronous rectification
• -Internal compensation for ease of use
• -SOT-23-6 package
• Pin-to-pin compatible with LMR14010Aand TPS560430
• Various options in pin-to-pin compatible package -PFM and forced PWM (FPWM) options
• Create a custom design using the LMR50410 with the WEBENCH ® Power Designer

• Major appliances
• PLC, DCS, and PAC
• Smart meters
• General purpose wide VIN power supplies

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

Table 6-1. Pin Functions

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

Table 6-1. Pin Functions

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: V IN = 4 V to 36 V.

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 = 80 °C /W can be achieved. For design information see Maximum Output Current versus Ambient Temperature.

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 = 80 °C /W can be achieved. For design information see Maximum Output Current versus Ambient Temperature.

The LMR50410 is a step-down DC-to-DC converter. It is typically used to convert a higher input voltage to a lower output DC voltage with a maximum output current of 1 A. The following design procedure can be used to select components for the LMR50410. Alternately, the WEBENCH® software can be used to generate complete designs. When generating a design, the WEBENCH® software utilizes iterative design procedure and accesses comprehensive databases of components. Go to ti.com for more details.