SLUSES3 Data sheet

SLUSES3A October 2023 – December 2023 UCC25660

PRODUCTION DATA

Package Options

Mechanical Data (Package|Pins)

DDB|14
- MPDC008

Thermal pad, mechanical data (Package|Pins)

Orderable Information

sluses3a_oa

8.2.2.20 Burst Mode Programming

The LL pin voltage (VLLB) and the resistor divider that connected to the LL pin allow the designer to set the HFBurstEntry and LFBurstEntry thresholds as shown below.

Equation 72.

V L L B = \frac{R_{L L_l o w e r} \cdot V 5 P}{R_{L L_u p p e r} + R_{L L_l o w e r}}

Equation 73.

V L L A = V L L B + \frac{R_{L L_l o w e r} R_{L L_u p p e r}}{R_{L L_u p p e r} + R_{L L_l o w e r}} \cdot I_{L L P r g m}

As shown in Table 7-2, (VLLA-VLLB) voltage determines the VLLB/HFBurstEntry ratio.

For this design, (VLLB/HFBurstEntry) = 0.55 is considered. So, Max voltage of (VLLA-VLLB) should be below 1.391V.

Then HFBurstEntry is related to LL pin voltage as below:

Equation 74.

H F B u r s t E n t r y = \frac{V L L B}{0.55} = 1.818 \cdot V L L B

The LFBurstEntry is always related to LL pin voltage as below:

Equation 75.

L F B u r s t E n t r y = \frac{V L L B}{0.6} = 1.667 \cdot V L L B

For this design, VLLB= 1V and VLLA=(Max voltage of (VLLA-VLLB))-0.1V are considered. By substituting these values in Equation 72, Equation 73, R_LLupper, R_LLlower can be obtained as 641k and 161k respectively.

Finally R_LLupper= 549kΩ and R_LLlower=140kΩ are chosen for this design.

Then final burst entries will be calculated as below.

Equation 76.

V L L B = \frac{140 k \cdot 5}{140 k + 549 k} = 1.016 V

Equation 77.

V L L A = 1.016 V + \frac{140 k \cdot 549 k}{140 k + 549 k} \cdot 10 μ A = 2.131 V

Equation 78.

V L L A - V L L B = 1.116 V

Equation 79.

H F B u r s t E n t r y = 1.818 \cdot 1.016 = 1.847 V

Equation 80.

L F B u r s t E n t r y = 1.667 \cdot 1.016 = 1.693 V