tb62733ftg TOSHIBA Semiconductor CORPORATION, tb62733ftg Datasheet - Page 5

• Manufacturer Part Number: tb62733ftg
• Description: Charge Pump Type Dc/dc Converter For White Led Driver
• Manufacturer: TOSHIBA Semiconductor CORPORATION

TOSHIBA
This datasheet is tentative, the values and contents are subject to change without any notice.
  2. Out put from C1 and C2 yjat are charged
   By connecting C1 and C2 through internal switch as shown in the figure
  3. By repeating the operation 1 and 2 described above, the voltage is
 1.5 times Up converting operation
  This device performs up converting to output voltage (Vout) that is converted 1.5 times from input voltage. (Vin)
 The actual output (Vout) will be differ by the conditions of output current, external parts, application circuit and
£Principle of Basic Operation¤
The following is the explanation for basic operation of 1.5 time
 
  1. Charging to C1 and C2
 
up converting
The input voltage will be allowed from 2.8V to 4.2V.
so on, because the feed back voltage will be hold at the constant voltage.
The ripple voltage of the output will be approximately 100mV peak to peak.
Explanation of Operations
By connecting C1 and C2 through internal Switch as shown in the figure
the half of Vin.(Vc1=1/2Vin)
Actually, the voltage is slightly lower than 1/2 Vin due to on resistance
Of internal switch and equivalent resistance of C1.
Thus, C2 is also charged up to 1/2 Vin as well.
C1 and C2 is charged. In this case, the C1 is charged up to around
At this time, Vout is added by the voltage charged to C1 and C2, therefore
supplied to Vout around 1.5 times of Vin.
The charged energy of C1 and C2 output to Vout.
Vout voltage is approximately 3/2 Vin.
                                            

Vin
Vin
27-Jul-04 (Rev1.7)TB62733FTG (Page. 5)
 TB62733FTG
C1
C2
C1
C2
Vout
Vout