BQ24266: Would you help review our pre-charge data log?

PYTsai

Part Number: BQ24266

I had doing data log of BQ24266 charge voltage & current, the pre-charge function seems not meet the charge profile of the datasheet. Would you help review the data log below, if the device are working correctly?

Riset= 470ohm.

System off mode testing.

Voltage	AvgCurrent
0	0
0	0
0	0
0	0
2907	753
2907	753
2910	654
2910	654
2913	585
2913	585
2917	534
2920	493
2922	459
2924	431
2926	406
2928	386
2930	367
2931	352
2933	337
2934	324
2935	313
2937	301
2937	292
2938	283
2940	275
2940	268
2941	260
2942	254
2943	247
2944	242
2944	236
2945	232
2946	227
2947	218
2947	214
2949	210
2949	207
2950	203
2950	199
2950	197
2952	193
2952	191
2952	187
2953	184
2953	182
2954	179
2954	177
2955	175
2955	173
2955	170
2956	169
2957	167
2957	165
2957	163
2957	161
2958	159
2958	158
2958	156
2959	154
2959	152
2960	150
2960	149
2961	147
2961	146
2961	144
2962	143
2962	142
2962	141
2962	139
2963	139
2963	138
2963	136
2964	135
2964	134
2964	133
2965	132
2965	131
2965	130
2966	129
2966	128
2966	127
2966	126
2967	125
2967	125
2967	124
2967	123
2968	122
2968	121
2968	121
2968	120
2969	119
2969	117
2969	117
2970	117
2970	116
2970	115
2970	115
2970	114
2971	113
2970	113
2971	113
2971	111
2971	111
2971	110
2972	110
2972	109
2972	109
2973	108
2973	108
2973	107
2973	107
2973	106
2974	106
2974	105
2974	104
2975	104
2975	103
2975	103
2975	102
2975	102
2976	101
2976	101
2976	101
2976	100
2976	100
2977	99
2977	99
2977	99
2977	98
2977	98
2978	98
2978	97
2978	97
2978	97
2978	96
2978	96
2979	95
2979	95
2979	95
2979	95
2979	95
2979	94
2979	94
2980	94
2980	93
2980	93
2980	93
2981	93
2981	92
2981	92
2981	91
2981	91
2981	91
2982	91
2982	90
2982	90
2982	90
2983	89
2982	90
2982	89
2983	89
2983	89
2983	89
2983	88
2983	88
2984	88
2984	88
2984	87
2984	87
2984	87
2984	87
2984	87
2985	87
2985	86
2985	86
2985	86
2985	86
2985	85
2986	85
2986	85
2986	85
2986	85
2986	85
2986	85
2986	85
2986	85
2987	85
2987	85
2987	85
2987	85
2987	85
2988	85
2988	85
2988	85
2988	85
2988	81
2988	81
2989	81
2989	81
2989	81
2989	81
2989	81
2989	80
2989	81
2990	81
2990	80
2990	80
2990	80
2990	80
2990	79
2990	79
2990	79
2991	79
2991	79
2991	79
2991	79
2991	78
2991	78
2992	78
2992	78
2992	78
2992	78
2992	77
2992	78
2992	77
2992	77
2993	77
2993	77
2992	77
2993	76
2993	77
2993	76
2994	76
2994	76
2994	76
2994	76
2994	75
2994	76
2994	75
2994	75
2994	75
2994	75
2994	75
2995	75
2995	75
2995	75
2995	75
2995	74
2996	74
2995	74
2996	74
2996	74
2996	74
2996	73
2996	74
2997	73
2997	74
2997	73
2997	73
2997	73
2997	73
2997	73
2997	73
2997	73
2998	73
2998	73
2998	73
2998	72
2998	73
2998	73
2998	72
2998	72
2998	72
2998	72
2999	72
2999	72
2999	72
2999	72
2999	71
2999	72
3000	71
3000	71
3000	71
3000	71
3000	71
3000	71
3000	71
3000	71
3000	71
3000	70
3000	71
3001	70
3001	70
3001	70
3001	70
3001	70
3001	70
3001	70
3002	70
3002	70
3002	70
3002	70
3002	69
3002	69
3002	69
3002	69
3002	69
3003	69
3003	69
3003	69
3003	69
3003	69
3003	69
3003	69
3003	68
3004	69
3003	68
3004	69
3004	68
3004	68
3004	68
3004	68
3004	68
3005	68
3004	68
3005	68
3005	68
3005	68
3005	68
3005	67
3005	68
3005	67
3006	67
3005	67
3006	67
3006	67
3006	67
3006	67
3006	67
3006	67
3007	67
3006	67
3006	67
3007	67
3007	67
3007	67
3007	66
3007	67
3007	67
3007	66
3007	66
3008	66
3008	66
3008	66
3008	66
3008	66
3008	66
3008	66
3008	66
3008	66
3008	66
3009	66
3008	66
3009	66
3009	66
3009	66
3009	66
3009	66
3010	66
3010	66
3010	66
3009	66
3010	66
3010	66
3010	65
3010	66
3010	66
3010	65
3010	65
3010	65
3010	66
3010	65
3010	65
3011	65
3011	65
3011	65
3011	65
3012	65
3011	65
3012	65
3011	65
3011	65
3012	65
3012	64
3012	65
3012	64
3012	65
3013	64
3012	64
3012	65
3012	64
3013	64
3013	625
3155	1841
3167	1836
3171	1833
3174	1830
3177	1827
3181	1824
3183	1822
3186	1820
3189	1817
3194	1811
3196	1809
3198	1809
3201	1807
3203	1805
3205	1804
3207	1802
3210	1802
3212	1799
3214	1797
3218	1793
3220	1793
3222	1792
3224	1793
3226	1790
3228	1792
3230	1791
3232	1791
3233	1786
3237	1786
3239	1786
3240	1785
3242	1786
3244	1786
3246	1785
3248	1785
3249	1786
3251	1785
3253	1785
3254	1785
3256	1785
3258	1784
3261	1784
3262	1783
3264	1784
3266	1783
3267	1784
3269	1782
3270	1781
3271	1780
3273	1782
3275	1782
3276	1781
3279	1779
3281	1779
3282	1778
3283	1780
3285	1779
3286	1778
3287	1778
3289	1779
3291	1779
3291	1778
3294	1778
3295	1778
3297	1777
3298	1776
3299	1775
3301	1775
3302	1772
3303	1774
3305	1775
3307	1775
3308	1775
3309	1775
3310	1775
3311	1774
3313	1775
3315	1775
3316	1775
3318	1775
3318	1775
3320	1775
3321	1775
3322	1775
3323	1775
3325	1774
3326	1775
3328	1775
3329	1775
3330	1775
3331	1775
3333	1775
3334	1774
3335	1774
3337	1774
3338	1774
3339	1774
3340	1774
3341	1773
3342	1774
3344	1774
3345	1774
3346	1774
3347	1775
3348	1771
3349	1763
3350	1765
3350	1765
3351	1767
3354	1767
3355	1768
3355	1767
3357	1767
3357	1768
3358	1768
3359	1767
3360	1767
3361	1767
3362	1768
3364	1768
3365	1768
3366	1768
3367	1767
3368	1763
3368	1764
3369	1764
3371	1764
3371	1765
3372	1765
3374	1764
3375	1763
3376	1764
3377	1764

over 5 years ago

0 Paul Yeh over 5 years ago

TI__Genius 14445 points

Hi,

Is your test in customer's system or TI EVM board?

Could I review your circuit?

From your setting, it seems CC setting should be 2.55A but from your test, it is only 1.76A, is it correct.

And from our datasheet, the BAT_short voltage is around 2.9V~3.1V, so just thinking can you also check battery voltage ripple situation? May this case.

BTW, how about battery voltage is lower than 2.9V condition, is charge current stable?

Thanks

0 PYTsai over 5 years ago in reply to Paul Yeh

TI__Genius 10135 points

Hi Paul,

1. The test done on customer's PCB

2. Yes, CC setting is 2.55A . Current limit is on type C adapter. (it followed type C adapter current limit)

3. The charge current is not stable when the battery voltage is lower than 2.9V.

4. battery voltage ripple waveform and schematics attached below.

0 Joel Hernandez II over 5 years ago in reply to PYTsai

TI__Mastermind 25800 points

Hey PYT,

The MOSFET Q4 should be a P-Channel FET and it is also currently connected backwards.

Using a P-Ch MOSFET, the drain should be connected to BAT while the source should be connected to SYS. The forward conduction path of the body diode needs to connect from BAT to SYS.

Try performing the same test with Q5 removed.

Regards,
Joel H

Power management

Power management forum

BQ24266: Would you help review our pre-charge data log?