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admv4640 pll lock issue

Category: Datasheet/Specs
Product Number: ADMV4640

Hey,

I'm using the admv4640 with the following configurations:

{ADMV4640_SPI_CONFIG_1_ADD, 0x99}, // SPI configuration

{ADMV4640_SPI_CONFIG_1_ADD, 0x18}, // SPI configuration

{ADMV4640_MUTE_UNLOCK_ADD, 0x00}, // Not mute if PLL unlock

{ADMV4640_FRAC1_L_ADD, 0x00}, // PLL Frac-N Word

{ADMV4640_FRAC1_M_ADD, 0x00}, // PLL Frac-N Word

{ADMV4640_FRAC1_H_ADD, 0x00}, // PLL Frac-N Word

{ADMV4640_MOD_L_ADD, 0x01}, // DSM MODULUS LSB

{ADMV4640_MOD_H_ADD, 0x00}, // DSM MODULUS MSB

{ADMV4640_SYNTH_ADD, 0x01}, // Enable Feedback Divider, Disable 2x Prescalar

{ADMV4640_R_DIV_ADD, 0x01}, // PLL R Divider Word

{ADMV4640_REFERENCE_ADD, 0x04}, // Disable reference doubler and reference doubler

{ADMV4640_SD_CTRL_ADD, 0x00}, // Disable Sigma Delta

{ADMV4640_MULTI_FUNC_SYNTH_CTRL_022B_ADD, 0x01}, // ADI's internal register

{ADMV4640_MULTI_FUNC_SYNTH_CTRL_022D_ADD, 0xA1}, // Enable Phase Detector and Charge Pump

{ADMV4640_CP_CURR_ADD, 0xC8}, // Set charge pump current

{ADMV4640_VCO_FSM_ADD, 0x27}, // Set charge pump bleed current

{ADMV4640_VCO_BAND_DIV_ADD, 0x05},

{ADMV4640_VCO_TIMEOUT_L_ADD, 0x02},

{ADMV4640_VCO_TIMEOUT_H_ADD, 0x00},

{ADMV4640_VCO_TIMEOUT_H_ADD, 0x00},

{ADMV4640_INT_H_ADD, 0x01}, // PLL Integer-N Word

{ADMV4640_INT_L_ADD, 0x80}, // PLL Integer-N Word

{ADMV4640_LOCK_DETECT_CONFIG_ADD, 0x40}, // Optimze lock detection timing

{ADMV4640_MUTE_MASK_CONTROL_ADD, 0x03}, // Set Mute Mask

{ADMV4640_ON_MASK_CONTROL_ADD, 0x03}, // Set RX ON Mask

{ADMV4640_ADC_CONTROL_ADD, 0xC7}, // Configure ADC

{ADMV4640_RFBIAS_CONTROL1_ADD, 0x02}, // Set IF bias current

{ADMV4640_RFBIAS_CONTROL2_ADD, 0x33}, // Set LNA bias current

{ADMV4640_RFBIAS_CONTROL3_ADD, 0x48}, // Set LO bias current

{ADMV4640_MIXER_CONTROL1_ADD, 0x09}, // Set Mixer bias current

{ADMV4640_MIXER_CONTROL2_ADD, 0x09}, // Set Mixer bias current

{ADMV4640_MUXOUT_ADD, 0x01}, // Set MUXOUTPLLLock

{ADMV4640_MUTE_UNLOCK_ADD, 0x01}, // Mute if PLL unlock

{ADMV4640_REG024C_ADD, 0x40}, // Optimze PLL timing

{ADMV4640_VCO_FSM_ADD, 0x90}, // Optimze PLL timing

{ADMV4640_REG021A_ADD, 0x38}, // Optimze PLL timing

I'm using a reference clock of 10 Mhz.

I'm using Revgo's configurations requirements.

However,  The pll lock bit on register 0x24D is never set.

What am I doing wrong?

Tnx in advance.