Agilex™ 5 FPGAs and SoCs Device Data Sheet

ID 813918
Date 10/13/2025
Public
Document Table of Contents

HPS I2C Timing Characteristics

Table 101.  HPS I2C Timing Requirements For specification status, see the Data Sheet Status table
Symbol Description Standard Mode Fast Mode Unit
Min Max Min Max
Fclk Serial clock (SCL) clock frequency 100 400 KHz
Tclk Serial clock (SCL) clock period 10 2.5 μs
Tclk_jitter I2C clock output jitter 2 2 %
THIGH 165 SCL high period 4166 0.6167 μs
TLOW 168 SCL low period 4.7169 1.3170 μs
TSU_DAT Setup time for serial data line (SDA) data to SCL 0.25 0.1 μs
THD_DAT 171 Hold time for SCL to SDA data 0 3.15 0 0.6 μs
TVD_DAT and TVD_ACK 172 SCL to SDA output data delay 3.45173 0.9174 μs
TSU_STA Setup time for a repeated start condition 4.7 0.6 μs
THD_STA Hold time for a repeated start condition 4 0.6 μs
TSU_STO Setup time for a stop condition 4 0.6 μs
TBUF SDA high pulse duration between STOP and START 4.7 1.3 μs
Tscl_r 175 SCL rise time 1,000 20 300 ns
Tscl_f 175 SCL fall time 300 6.54 300 ns
Tsda_r 175 SDA rise time 1,000 20 300 ns
Tsda_f 175 SDA fall time 300 6.54 300 ns
Figure 23. I2C Timing Diagram
165 You can adjust THIGH using the ic_ss_scl_hcnt or ic_fs_scl_hcnt register.
166 The recommended minimum setting for ic_ss_scl_hcnt is 428. Refer to the SCL_High_time equation in the Hard Processor System Technical Reference Manual.
167 The recommended minimum setting for ic_fs_scl_hcnt is 75. Refer to the SCL_High_time equation in the Hard Processor System Technical Reference Manual.
168 You can adjust TLOW using the ic_ss_scl_lcnt or ic_fs_scl_lcnt register.
169 The recommended minimum setting for ic_ss_scl_lcnt is 464. Refer to the SCL_Low_time equation in the Hard Processor System Technical Reference Manual.
170 The recommended minimum setting for ic_fs_scl_lcnt is 163. Refer to the SCL_Low_time equation in the Hard Processor System Technical Reference Manual.
171 THD_DAT is affected by the rise and fall time.
172 TVD_DAT and TVD_ACK are affected by the rise and fall time, as well as the SDA hold time (set by adjusting the ic_sda_hold register).
173 Use maximum SDA_HOLD = 240 to be within the specification.
174 Use maximum SDA_HOLD = 60 to be within the specification.
175 Rise and fall time parameters vary depending on external factors such as the characteristics of the I/O driver, pull-up resistor value, and total capacitance on the transmission line.