EP1C12F256I7N Datasheet, PDF (262/385 Pages) List of Unclassifed Manufacturers – Cyclone Device Handbook, Volume 1

Cyclone Device Handbook, Volume 1
Figure 12–6. Voltage-Controlled Synchronous Switching Regulator
V_IN
Voltage-Controlled
Oscillator (VCO)
V_OUT
Maximum Output Current
Select an external MOSFET switching transistor (optional) based on the
maximum output current that it can supply. Use a MOSFET with a low
on-resistance and a voltage rating high enough to avoid avalanche
breakdown. For gate-drive voltages less than 9-V, use a logic-level
MOSFET. A logic-level MOSFET is only required for topologies with a
controller IC and an external MOSFET.
Selecting Voltage Regulators
Your design requirements determine which voltage regulator you need.
The key to selecting a voltage regulator is understanding the regulator
parameters and how they relate to the design.
The following checklist can help you select the proper regulator for your
design:
■ Do you require a 3.3-V, 2.5-V, and 1.5-V output (V_OUT)?
■ What precision is required on the regulated 1.5-V supplies (line and
load regulation)?
■ What supply voltages (V_IN or V_CC) are available on the board?
■ What voltage variance (input voltage range) is expected on V_IN or
V_CC?
■ What is the maximum I_CC (I_OUT) required by your Altera^® device?
■ What is the maximum current surge (I_OUT(MAX)) that the regulator
will need to supply instantaneously?
12–8
Preliminary
Altera Corporation
May 2008