Features: ` 3.0-V to 6.0-V Input Voltage Range
` *1 and*1.5 Charge Pump
` Fully Programmable Current with I2C
64 Dimming Steps with 25mA Maximum(Sub and Main Display Banks)
4 Dimming Steps with 80mA Maximum(DM5 for Auxiliary Application)
` 2% Current Matching for Sub LEDs at Light Load Condition (Each 100mA)
` 750-kHz Charge Pump Frequency
` Continuous 230-mA Maximum Output Current
` Auto Switching Between*1 and *1.5 Mode for Maximum Efficiency
` Built-in Soft Start and Current Limit
` Hardware Enable/Disable
` Open Lamp DetectionApplication· Cellular Phones
· PDA, PMP, GPS (Up To 4 Inch Display)
· Multidisplay Handheld DevicesPinout
Specifications
| |
VALUE |
UNIT |
| VI Input voltage range (all pins) |
0.3 to 7 |
V |
| MAX Output current limit |
650 |
mA |
| HBM ESD Rating (2) |
2 |
kV |
| CDM ESD Rating(3) |
500 |
V |
| MM ESD Rating(4) |
200 |
V |
| TA Operating temperature range |
40 to 85 |
|
| TJ Maximum operating junction temperature |
150 |
|
| TST Storage temperature |
55 to 150 |
|
(1) Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
(2) The Human body model (HBM) is a 100-pF capacitor discharged through a 1.5-kW resistor into each pin. The testing is done accordingJEDECs EIA/JESD22-A114.
(3) Charged Device Model
(4) Machine Model (MM) is a 200-pF capacitor discharged through a 500-nH inductor with no series resistor into each pin. The testing isdone according JEDECs EIA/JESD22-A115.Description
The TPS60251 is a high efficiency, constant frequency charge pump DC/DC converter that uses a dual mode 1×and 1.5×conversion to maximize efficiency over the input voltage range. It drives up to five white LEDs for a main display and up to two white LEDs for a sub display with regulated constant current for uniform intensity. By utilizing adaptive 1×/1.5× charge pump modes and very low-dropout current regulators, the TPS60251 achieves high efficiency over the full 1-cell lithium-battery input voltage range.
Four enable inputs, ENmain, ENsub1, ENsub2, and ENaux, available through I2C, TPS60251 are used for simple on/off controls for the main, sub1, sub2, and DM5 displays, respectively. To lower operating current when using one sub display LED, the device provides independent operation in sub display LEDs.
The TPS60251 is available in a 24-pin 4mmx4mmthin QFN.
TPS60251 Data Sheet
