User's Manual

Page 39
BitaTek Co., Ltd. Copyright protected. All rights reserved.
NO. 115 Wugong 3rd Rd., Tel [phone]
Wugu Dist., New Taipei City 248, Taiwan (R.O.C.) Fax[phone]
Expected source is PMI’s
VREG_BST_BYP
Output current per
LED
Flash
Torch
-
-
-
-
1000
200
mA
mA
NOTE: All specifications apply at VPH_PWR = 3.6 V, T = -30 to +85ºC unless noted otherwise.
3.5.10. Display backlight (WLEDs)
The FREY M1 supports WLEDs with a boost converter that generates the high voltage needed
for powering a string of WLEDs, plus four output drivers for sinking the current from WLED
strings.
Parameter
Conditions
Min
Typ
Max
Units
Operational input voltage
VPH_PWR
2.5
-
4.75
V
Input voltage for full
brightness
2 strings (~16 WLEDs)
4 strings (~28 WLEDs)
I_led = 20 mA per string
V_out = 28 V across panel
V_out = 24 V across panel
2.8
3.6
-
-
-
-
V
V
Output voltage
6.0
-
28.5
V
Over-current protection
Programmable, set to 980 mA
830
980
1200
mA
Switching frequency
0.6
0.8
1.6
MHz
Efficiency
Peak
Average
Light load
VDD = 3.6 V, 25°C, F_sw = 0.8
MHz
I_out = 15 mA/string (x4), 13.5 V
out
I_out = 5 to 25 mA/string (x4)
I_out = 1 to 5 mA/string (x4); PSM
en
-
-
-
86
80
75
-
-
-
%
%
%
Full-scale current range
Programmable range, 2.5 mA
step
0
-
30
mA
CABC frequency
20
-
40
KHz