XRP7740ILB-F Exar Corporation, XRP7740ILB-F Datasheet

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... Industrial: ATE, DC-DC converters, Video Processing Plasma Display Panel (PDP) Networking and Telecommunications Equipment Exar Corporation 48720 Kato Road, Fremont CA, 94538 • (510) 668-7000 • FAX (510) 668-7017 • Quad-Output Digital PWM Buck Controller KEY FEATURES Four switching buck (step-down) controllers each with internal FET drivers. Two controllers (2 & ...

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REV 1.1.0 ABSOLUTE MAXIMUM RATINGS These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. Exposure to absolute maximum ...

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REV 1.1.0 LOW DROP-OUT REGULATOR PARAMETER MIN LDOOUT Output Voltage 3.15 (LDO=LOW) LDOOUT Output Voltage 4.75 (LDO=HIGH) LDOOUT Short Circuit 110 Current Limit AUXILIARY ADCs PARAMETER MIN ADC Resolution Linearity Error Integral Linearity Error Differential Input Dynamic Range VIN1 6.5 ...

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REV 1.1.0 Digital Input/Output Pins 3.3V CMOS logic compatible. 5V tolerant, maximum rating of 6.0V PARAMETER MIN Input Pin Low Level Input Pin High Level Input Pin Leakage Current Input pin Capacitance Output Pin Low Level Output Pin High Level ...

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REV 1.1.0 XRP7740 INTERNAL BLOCK DIAGRAM VOUT1 PreScaler Vtar DAC VOUT2 PreScaler Vtar DAC VOUT3 VOUT4 VCC LDO VDD GPIO 0-3 GPIO SDA,SCL I2C EXAR RESERVES THE RIGHT TO MAKE CHANGES TO THIS DATASHEET. EXAR CONFIDENTIAL, PRELIMINARY & PROPRIETARY. DO ...

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REV 1.1.0 XRP7740 PACKAGE OUTLINE – QFN 1 AVDD 2 DVDD 3 GPIO0 4 GPIO1 5 GPIO2 6 GPIO3 7 GPIO4 8 GPIO5 9 ENABLE 10 DGND EXAR RESERVES THE RIGHT TO MAKE CHANGES TO THIS DATASHEET. EXAR CONFIDENTIAL, PRELIMINARY ...

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REV 1.1.0 PIN DESCRIPTION QFN PIN NAME PIN # Power source for the internal linear regulators to generate VCCA, VDD and the Standby LDO (LDOOUT). Place a decoupling capacitor close to the controller IC. 39 VIN1 Also used in UVLO1 ...

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REV 1.1.0 These pins can be configured as inputs or outputs to implement custom flags, power good signals and enable/disable controls. A GPIO pin can also be 3,4,5,6 GPIO0-GPIO3 programmed as an input clock synchronizing IC to external clock. Refer ...

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... REV 1.1.0 Part Number Junction Temperature Range XRP7740ILB-AAAA-F.......................-40 XRP7740ILBTR-AAAA-F..................-40 The “AAAA” Suffix will differentiate the configuration of a specific customer. EXAR RESERVES THE RIGHT TO MAKE CHANGES TO THIS DATASHEET. EXAR CONFIDENTIAL, PRELIMINARY & PROPRIETARY. DO NOT DISTRIBUTE OR COPY. Quad-Output Digital PWM Buck Controller ...

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REV 1.1.0 APPLICATION INFORMATION, Typical Performance Data 25°C, unless otherwise specified. A 12Vin Efficiency: Single Channel 300kHz - Channels not in use are disabled FET: Si4944; Inductor: 744314xxx 7x7x5mm 12Vin Efficiency: Single Channel 300kHz - Channels not ...

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REV 1.1.0 APPLICATION INFORMATION (Cont) CH1:3.3V CH2:5V CH3:1V CH4:1.8V Simultaneous Start-up Configuration CH1:3.3V CH2:5V CH3:1V CH4:1.8V Sequential Start-up Configuration CH1: Vout (5V) Startup into 3V prebias - 5V output EXAR RESERVES THE RIGHT TO MAKE CHANGES TO THIS DATASHEET. EXAR ...

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REV 1.1.0 APPLICATION INFORMATION (Cont) CH1:Iout (1A/div) CH2: Vout (3.3V) Load Transient Response Temperature Regulation 1.0 V out (+/- 1% Vo window) EXAR RESERVES THE RIGHT TO MAKE CHANGES TO THIS DATASHEET. EXAR CONFIDENTIAL, PRELIMINARY & PROPRIETARY. DO NOT DISTRIBUTE ...

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REV 1.1.0 Features and Benefits General DPWM Benefits: - Eliminate temperature and time variations associated with passive components in: o Output set point o Feedback compensation o Frequency set point o Under voltage lock out o Input voltage measurement o ...

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REV 1.1.0 XRP7740 FUNCTIONAL DESCRIPTION AND OPERATION The XRP7740 is a quad-output digital pulse width modulation (DPWM) controller with integrated gate drivers for the use in synchronous buck switching regulators. Each output voltage can be programmed from 0.9V to 5.1V ...

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REV 1.1.0 Chip Power-Up The figure below shows the power-up sequence of XRP7740 during the normal operation. The startup stage is divided into three phases. The first phase is the internal LDO power-up phase. The second phase is the configuration ...

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REV 1.1.0 Standby Low Drop-out Regulator This 100mA low drop-out regulator can be programmed as 3. SET_STBLDO_EN_CONFIG register. Its output is seen on the LDOOUT Pin. This LDO is fully controllable via the Enable Pin (configured to ...

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REV 1.1.0 Under Voltage Lockout (UVLO) There are two locations where the under voltage can be sensed: VIN1 and VIN2. The SET_UVLO_WARN_VINx register that sets the under voltage warning set point condition at 100mV increments. When the warning threshold is ...

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REV 1.1.0 Output Voltage Setting and Monitoring The Output Voltage setting is controlled by the SET_VOUT_TARGET_CHx register. This register allows the user to set the output voltage with a resolution of 50mV for output voltages between 0 and 2.5V and ...

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REV 1.1.0 Over-Voltage Protection (OVP) The Over-Voltage Protection (OVP) SET_OVVP_REGISTER sets the over-voltage condition in predefined steps per channel. The over-voltage protection is always active even during soft-start condition. When the over-voltage condition is tripped, the controller will shut down ...

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REV 1.1.0 Over-Current Fault Handling When an over-current condition occurs, PWM drivers in the corresponding channels are disabled. After a 200ms timeout, the controller is re-powered and soft-start is initiated. When the over-current condition is reached the controller will check ...

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REV 1.1.0 Soft-Stop The SET_PD_FALL_CHx register bit register. This register specifies the soft-stop delay and ramp (fall- time) characteristics for when the chip receives a channel disable indication from the Host to shutdown the channel. Bits [15:10] ...

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REV 1.1.0 PWM Switching Frequency The PWM switching frequency is set by choosing the corresponding oscillator frequency and clock divider ratio in the SET_SW_FREQUENCY register. Bits [6:4] set the oscillator frequency and bits [2:0] set the clock divider. The tables ...

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REV 1.1.0 Maximum Duty Cycle The maximum duty cycle is dictated by the minimum required time to sample the current when the low side MOSFET is on. For the XRP7740, the minimum required sampling time is about 16 clock cycles ...

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REV 1.1.0 Frequency Synchronization Function and External Clock The user of the XRP7740 can choose to use an external source as the primary clock for the XRP7740. This function can be configured using the SET_SYNC_MODE_CONFIG register. This register sets the ...

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REV 1.1.0 Master/Slave configure of the XRP7740 External Clock Synchronization Master Slave combination When an external clock is used, the user will need to setup the master to also have an external clock in function. All of the same rules ...

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REV 1.1.0 Phase Shift Each switching channel can be programmed to a phase shift of the multiples of 90 degrees [for a 4 phase configuration] or 120 degrees [for a 3 phase configuration]. Two or more of the channels can ...

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REV 1.1.0 Fault and Warning Indication The GPIOs can be configured to signal Fault or Warning conditions when they occur in the chip. Each GPIO can be configured to signal one of the following: • OCP Fault on Channel 1 ...

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REV 1.1.0 load current forces the energy surplus in the inductor to be absorbed by Cout. This causes an overshoot in output voltage that is corrected by power switch reduced duty cycle. Use the following equation to calculate Cout: Where: ...

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REV 1.1.0 In general, the total input voltage ripple should be kept below 1.5% of VIN. The input voltage ripple also has two major components: the voltage drop on the main capacitor contribution to Input voltage ripple by each term ...

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REV 1.1.0 REV 1.1.0 Package Drawing Package Drawing EXAR RESERVES THE RIGHT TO MAKE CHANGES TO THIS DATASHEET. EXAR RESERVES THE RIGHT TO MAKE CHANGES TO THIS DATASHEET. EXAR CONFIDENTIAL, PRELIMINARY & PROPRIETARY. DO NOT DISTRIBUTE OR COPY. EXAR CONFIDENTIAL, ...

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... EXAR Corporation does not recommend the use of any of its products in life support applications where the failure or malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect its safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives, in writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized ...