XRP7714ILB-0X18-F Exar Corporation, XRP7714ILB-0X18-F Datasheet - Page 16

• Manufacturer Part Number: XRP7714ILB-0X18-F
• Description: IC CTRLR PWM/LDO STP-DWN 40TQFN
• Manufacturer: Exar Corporation
• Series: -r

Specifications of XRP7714ILB-0X18-F

• Topology: Step-Down (Buck) Synchronous (4), Linear (LDO) (1)
• Function: Any Function
• Number Of Outputs: 5
• Frequency - Switching: 1.5MHz
• Voltage/current - Output 1: Controller
• Voltage/current - Output 2: Controller
• Voltage/current - Output 3: Controller
• W/led Driver: No
• W/supervisor: No
• W/sequencer: Yes
• Voltage - Supply: 4.75 V ~ 25 V
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: *
• Package / Case: *
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant
• Other names: 1016-1699

If the over temperature condition occurs both the OTP and OTPW bits will be set in the
READ_OVV_UVLO_OVT_FLAG register and the IC will shut down all channels (but I
operational). The actual over temperature threshold can be set by the user by using a 7bit
SET_THERMAL_SHDN register with an LSB of 5K.
If the over temperature fault condition clears, then the IC can be set to restart the chip
automatically. The restart temperature threshold can be set by the SET_THERMAL_RESTART
register.
O
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 with a resolution of 100mV for output voltages between 2.6V and 5.1V. Output
voltages higher than 5.1V can be achieved by adding an external voltage divider network. The
output voltage of a particular channel can be read back using the READ_VOUTx register.
Per the equation below, for values between 0.9V and 5.1V the output voltage is equal to the binary
number stored in the SET_VOUT_TARGET_CHx register multiplied by 50mV. When programming an
output voltage from 2.6V to 5.1V, odd binary values should be avoided. As a result, the set
resolution for an output voltage higher than 2.5V is 100mV.
To set the output voltage higher than 5.1V, the user needs to add an external voltage divider. The
resistors used in the voltage divider should be below 10kΩ. The SET_VOUT_TARGET_CHx register
should be set to 0x32 which is equivalent to an output voltage of 2.5V without the external divider
network. The output voltage regulation in this case might exceed 2% due to extra error from the
resistor divider. R1 and R2 follows the definition below.
The XRP7714 can be programmed to regulate an output voltage lower than 0.9V. However, in this
case the specification of ±20mV output voltage accuracy is not guaranteed.
© 2011 Exar Corporation
Output Voltage from 0.9V to 5.1V
Output VOUT Higher Than 5.1V
Output Voltage Lower Than 0.9V
UTPUT
•
Over Temperature Fault
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