ADSP-BF537 Blackfin Processor Hardware Reference
20-19
Dynamic Power Management
a
When increasing the V
DDINT
voltage, the external FET switches
on for a longer period. The V
DDEXT
supply should have appropri-
ate capacitive bypassing to enable it to provide sufficient current
without drooping the supply voltage.
Controlling the Voltage Regulator
The on-chip core voltage regulator controller manages the internal logic
voltage levels for the V
DDINT
supply. The voltage regulator control regis-
ter (
VR_CTL
) controls the regulator (see
state of the
VR_CTL
register is maintained during power down modes and
hibernate. It is only set to its reset value by a powerup reset sequence.
Writing to
VR_CTL
initiates a PLL relock sequence, thus, the PLL repro-
gramming sequence must be followed after modifying
VR_CTL
.
The on-chip switching regulator can be modified in terms of its transient
behavior in the
GAIN
and
FREQ
fields of the
VR_CTL
register.
The two-bit
GAIN
field controls the internal loop gain of the switching reg-
ulator loop; this bit controls how quickly the voltage output settles on its
final value. In general, higher gain allows for quicker settling times but
causes more overshoot in the process.
Figure 20-3. Processor Voltage Regulator
V
DDEXT
V
DDINT
EXTERNAL COMPONENTS
VR
OUT[1-0]
Summary of Contents for Blackfin ADSP-BF537
Page 42: ...Contents xlii ADSP BF537 Blackfin Processor Hardware Reference ...
Page 90: ...Development Tools 1 32 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 138: ...Programming Examples 4 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 340: ...SDC Programming Examples 6 84 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 606: ...Programming Examples 9 94 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 660: ...Programming Examples 10 54 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 720: ...Electrical Specifications 11 60 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 840: ...Programming Examples 13 42 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 876: ...Programming Examples 14 36 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 958: ...Programming Examples 17 12 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1162: ...G 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...