Configuring the EVM
Table 4. Control Pin Interfaces for Hard Pin Mode (JP18 HWCTRL = HI)
(1) (2)
NAME
COMPONENT
DESCRIPTION
(TYPE)
Page Select pins for Hard Pin Mode
GPIO[5:0] pins are sampled on POR and select the ROM page
settings to initialize the registers as follows:
GPIO[5:0] STATES
(3)
DEVICE MODE / PAGE SELECT
000000
Hard Pin Mode, ROM Page 0
GPIO0
000001
Hard Pin Mode, ROM Page 1
JP19
GPIO1
JP20
000010
Hard Pin Mode, ROM Page 2
GPIO2
JP21
GPIO3
000011
Hard Pin Mode, ROM Page 3
JP22
GPIO4
JP23
000100
Hard Pin Mode, ROM Page 4
GPIO5
JP24
(2-level inputs)
…
…
111101
Hard Pin Mode, ROM Page 61
111101
Hard Pin Mode, ROM Page 61
111110
Hard Pin Mode, ROM Page 62
111111
Hard Pin Mode, ROM Page 63
S4
SYNC
Not used for Hard Pin Mode.
S5
XO MARGIN
Not used for Hard Pin Mode. Set all switch position to OFF.
(1)
Jumpers not listed in
are identical to functions described in
(2)
Refer to the ROM page configurations for Hard Pin Mode in the LMK03328 datasheet. These settings may not operate with the default
EVM configuration, and modification of the EVM hardware may be required to operate the intended Hard Pin Mode configuration. EVM
modification areas may include the crystal (Y1), PRIREF / SECREF input interfaces, OUT / STATUS output interfaces, and PLL1 / PLL2
loop filter C2 capacitor selection (switches S1 / S2).
(3)
GPIO[5:0] values are BCD representation of the ROM Page value.
4.3
Configuring the PLL Loop Filters
Each PLL of the LMK03328 has configurable PLL loop bandwidth with most loop filter components
integrated on-chip (C1, R2, C3, and R3). Only one loop filter capacitor, C2, needs to be connected
externally to LF1 (pin 34) for PLL1 and LF2 (pin 29) for PLL2.
LF1 and LF2 pins are each connected to 3-position SPST switches S1 and S2, respectively. This
conveniently allows the user to select between one of three C2 values per
. The C2 values were
chosen to work well for different PLL modes / loop bandwidths (BW).
Table 5. PLL Loop Filter C2 Selection
COMPONENT
NAME
DESCRIPTION
PLL1 Loop Filter C2 Capacitor Select
S1 Position ON
(1)
C2 value
Intended PLL Mode (Loop BW)
Pos. A
3300 pF
Integer-N (Wide, >100 kHz)
S1
LF1
Pos. B
0.033 uF
Fractional-N (Med, <100 kHz)
Pos. C
22 uF
Jitter Cleaner (Narrow, <1 kHz)
(1)
Only one position should be ON at a time (all others are OFF).
PLL2 Loop Filter C2 Capacitor Select
S2
LF2
S2 has the same capacitor selection table as above for S1.
15
SNAU184 – August 2015
LMK03328EVM User’s Guide
Copyright © 2015, Texas Instruments Incorporated