HMC860LP3E v01.0811 QUAD LOW NOISE HIGH PSRRLINEAR VOLTAGE REGULATOROutput Voltage Adjust There are several ways to adjust the output voltage for each regulator. A 5V setting for any output can be achieved by grounding the respective HVx (x=1,2,3,4) pin. Any other value requires an external resistor, connected between RDx and GND for a voltage higher than the default, or between VRx and RDx for a voltage lower than the default. The figures below show the values of the internal resistive dividers that set the default output voltage a. for 3V and b. for 4.5V and two examples of two different voltage settings: c. shows a default 3V output changed to 3.3V by connecting a 220k Ohm resistor between RDx and GND, while d. shows the same output adjusted to 2.5V by connecting a 120k Ohm resistor between VRx and RDx. The internal resistors have a temperature coefficient (TempCo) of +270ppm/°C. When the default output voltage is modified by using an external resistor with a different TempCo, the temperature behavior of the respective output will differ from this specification, although the difference will likely be very smal . 9 T M G - S IN N IO IT D N O R × 1 (R2 + RX) 1 VRX ≈VREF × 1+ R ×RX ≈ × 1+ R C VRX VREF (R2×RX) R2× (R1+RX) E For VRx > VRx_default; For VRx < VRx_default; W X = 1, 2, 3, 4 X = 1, 2, 3, 4 VREF=1.21 Resistor values in KΩ VREF=1.21 Resistor values in KΩ O VRx_default = 3V for VR1, VR2 & VR3 P VRx_default = 4.5V for VR4 Inf F or o m ra tip o r n ifc ur e n ,is hd e e d lbiv y e A r n y al oa g n D d evi tco e s p is la beclie ev eo d rtd o ebre sa: H ccur iattti e taen M d re ilicarbloew . H a o ve wev eC r, o n r o For price, delivery, and to place orders: Analog Devices, Inc., responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other poration, 2 Elizabeth Drive, Chelmsford, MA 01824 One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106 978-250-3343 tel • 978-250-3373 fax • O rights of third parties that may result from its use. Specifications subject to change without notice. No rd P e h r o nO e n : 7 -li 81 n - e 32 a 9- t 4 w 70 ww. 0 • Ohi rd tt e ite r on.lc inom license is granted by implication or otherwise under any patent or patent rights of Analog Devices. e at www.analog.com 9 - 8 Application Trademarks and registered trademarks are the property of their respective owners.Support: apps@ A h ppitlitcitae ti .oco n Sm upport: Phone: 1-800-ANALOG-D