Datasheet MYTNA1R84RELA2RA (Murata) - 9

MYTNA1R84RELA2RA
Document Category: Datasheet UltraBK™ 4A DC–DC Converter Module
Limitation of Input Voltage Slew rate
When starting the module with ramping Input Voltage up, the slew rate of the ramping should be managed for the proper operation. If Input Voltage ramping up is too steep, it would cause charge injection to the internal nodes via parasitic. The maximum slew rate of the Input Voltage ramp up when booting the module with Input Voltage is specified on the table 4 "Electronic Characteristics". Similarly, if the VIN slew late is too low compare with VOUT slew rate, it could prevent expected start-up behavior. To avoid hitting the maximum duty cycle operation, the VIN slew rate should satisfy the equation of (eq.1). As a reference, estimated value of the slew rate and start-up time for each output voltage is written in the follow table. VINSR_L is minimum of input voltage start-up slew rate. VINSR [V/ms] ≧ 0.2 × 𝑉𝑉𝑉𝑉𝑉𝑉𝑉𝑉[𝑉𝑉] − 0.1 (eq.1)
CALCULATION EXAMPLE OUTPUT VOLTAGE(V) VINSR_L(V/ms) VIN RISE TIME(ms) (0V to 12V)
1.8 0.26 46.2 1.2 0.14 85.7 1.0 0.1 120
Table.6 Minimum input voltage start-up slew rate and start-up time Detailed Description
The MYTNA1R84RELA2RA is a two-stage DCDC converter that is composed of a dual-phase charge pump- based DCDC converter and a dual-phase synchronous buck DCDC converter. The output voltage range supported from 0.7 to 1.8V (The output voltage range depend on the input voltage.) with load currents of up to 4A and up to 7.2W delivered to the external load. This module isn’t designed for the parallel operation.
Output Voltage Adjustment
The output voltage may be adjusted over a limited range by connecting an external trim resistor (Rtrim) between the Trim pin and AGND pin. The Rtrim must be a 1/10W (or larger) precision metal film type,±0.5% accuracy (or better) with low temperature coefficient, ±100 ppm/°C (or better). Mount the resistor close to the converter with very short leads or use a surface mount trim resistor. And do not connect any additional components between the Trim pin and Vout or between the Trim and Sense pins. Use only the specified connections.
Resistor Trim Equation
Rtrim[kohm] = 0.7164/(VOUT − 0.597) (eq.2) The equations above are only reference, so please be sure to check the output voltage and adjust Rtrim in user circumstances. To increase or decrease the output voltage, increase or decrease the Rtrim value.
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Copyright ©2020 Murata Manufacturing Co., Ltd. All rights reserved. Export Control Code : X0863 Document No :D90DH – 00072 MYTNA1R84RELA2RA A01 Page 9 of 26 Document Outline Product Description Features Typical Applications Efficiency Simplified Application Circuit Absolute Maximum Ratings(1)(2) Recommended Operating Conditions(1) Package Thermal Characteristics(1)(2) Electrical Characteristics Pin Configuration Pin Descriptions Functional Block Diagram Typical Performance Characteristics Thermal Deratings (Reference Data) Output Voltage Range Limitation of Input Voltage Slew rate Detailed Description Output Voltage Adjustment Resistor Trim Equation Output Voltage Remote Sense Function Remote Enable Function Soft start Function Power Good Operation Protections Over Current Protection and Short Circuit Protection Over Temperature Protection Soldering Guidelines Pb-free Solder Processes Dry Pack Information Application Performance Transient Performance Test Circuit Component Selection Input Fuse Input Capacitor Output Capacitor Packaging Information Moisture Sensitivity Level Package Drawing Recommended Board Land Pattern (Top View) Top Marking Specification Application Circuit Application Circuit Part List (Recommended) Application Board Example Tape and Reel Specification Order Codes Notices CAUTION Limitation of Applications Note Product Specification Sales contact Disclaimers Patent Statement Copyright and Trademark