Datasheet

ManualsBrandsLINEAR TECHNOLOGY ManualsPMICsPMIC - DC/DC voltage regulator Switched-capacitor voltage converter DFN 6

LTC3204-3.3/LTC3204-5/

LTC3204B-3.3/LTC3204B-5

3204fa

FEATURES

DESCRIPTIO

TYPICAL APPLICATIO

The LTC

3204-3.3/LTC3204-5/LTC3204B-3.3/LTC3204B-5

are low noise, constant frequency (1.2MHz) switched ca-

pacitor voltage doublers. The LTC3204-3.3/LTC3204B-3.3

can produce a regulated output voltage of 3.3V

from a minimum input voltage of 1.8V (2 alkaline cells)

whereas the LTC3204-5/LTC3204B-5 can produce 5V from

a minimum of 2.7V (Li-Ion battery) input.

LTC3204-3.3/LTC3204-5 feature automatic Burst Mode

operation at light loads to maintain low supply current

whereas LTC3204B-3.3/LTC3204B-5 feature constant

frequency operation at any load. Built-in soft-start circuitry

prevents excessive inrush current during start-up. Thermal

shutdown and current-limit circuitry allow the parts to

survive a continuous short-circuit from V

OUT

to GND.

High switching frequency minimizes overall solution

footprint by allowing the use of tiny ceramic capaci-

tors. In shutdown, the load is disconnected from the

input and the quiescent current is reduced to <1µA. The

LTC3204-3.3/LTC3204-5/LTC3204B-3.3/LTC3204B-5 are

available in a low proﬁle (0.75mm) 6-lead 2mm × 2mm

DFN package.

Low Noise Regulated

Charge Pump in 2 × 2 DFN

■

Fixed 3.3V or 5V Outputs

■

Range:

1.8V to 4.5V (LTC3204-3.3/LTC3204B-3.3)

2.7V to 5.5V (LTC3204-5/LTC3204B-5)

■

Output Current:

Up to 150mA (LTC3204-5/LTC3204B-5)

Up to 50mA (LTC3204-3.3/LTC3204B-3.3)

■

Automatic Burst Mode

Operation with I

= 48µA

(LTC3204-3.3/LTC3204-5)

■

Constant Frequency Operation at All Loads

(LTC3204B-3.3/LTC3204B-5)

■

Low Noise Constant Frequency (1.2MHz) Operation*

■

Built-In Soft-Start Reduces Inrush Current

■

Shutdown Disconnects Load from Input

■

Shutdown Current <1µA

■

Short-Circuit/Thermal Protection

■

Available in Low Proﬁle 6-Lead DFN Package

■

2 AA Cell to 3.3V

■

Li-Ion to 5V

■

USB On-The-Go Devices

■

White LED Drivers

■

Handheld Devices

Output Ripple vs Load Current

Burst Mode is a registered trademark of Linear Technology Corporation.

*Protected by U.S. Patents including 6411531.

APPLICATIO S

, LTC and LT are registered trademarks of Linear Technology Corporation.

All other trademarks are the property of their respective owners.

OFF ON

GND

SHDN

OUT

–

LTC3204-5/

LTC3204B-5

2.2µF 2.2µF

2.2µF

2.7V TO 5.5V

3204 TA01a

1, 7

OUTPUT CURRENT (mA)

OUTPUT RIPPLE (mVp-p)

50 75 100

3204 TA01b

125 150

OUTPUT CAPACITANCE = 2.2µF

= 3.6V

LTC3204B-5

LTC3204-5

Summary of content (12 pages)

PAGE 1
LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 Low Noise Regulated Charge Pump in 2 × 2 DFN FEATURES ■ ■ ■ ■ ■ ■ ■ ■ ■ ■ U ■ DESCRIPTIO Fixed 3.3V or 5V Outputs VIN Range: 1.8V to 4.5V (LTC3204-3.3/LTC3204B-3.3) 2.7V to 5.5V (LTC3204-5/LTC3204B-5) Output Current: Up to 150mA (LTC3204-5/LTC3204B-5) Up to 50mA (LTC3204-3.3/LTC3204B-3.3) Automatic Burst Mode® Operation with IQ = 48µA (LTC3204-3.3/LTC3204-5) Constant Frequency Operation at All Loads (LTC3204B-3.
PAGE 2
LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 AXI U RATI GS U W W W ABSOLUTE U W U PACKAGE/ORDER I FOR ATIO (Note 1) VIN to GND ................................................... –0.3V to 6V VOUT to GND ............................................. –0.3V to 5.5V SHDN to GND............................................... –0.3V to 6V VOUT Short-Circuit Duration ............................. Indeﬁnite Operating Temperature Range (Note 2) ...–40°C to 85°C Storage Temperature Range..................
PAGE 3
LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 TYPICAL PERFOR A CE CHARACTERISTICS U W (TA = 25°C, CFLY = CIN = COUT = 2.2µF unless otherwise speciﬁed) Oscillator Frequency vs Temperature 1.4 1.25 1.3 1.00 0.75 0.50 0.25 0.9 VIN = 4.5V 1.2 VIN = 2.4V 1.1 VIN = 1.8V 1.0 1.5 2.0 2.5 3.0 3.5 SUPPLY VOLTAGE (V) 4.0 0.8 –50 4.5 –20 10 40 70 TEMPERATURE (°C) 100 3204 G01 0.7 HIGH-TO-LOW THRESHOLD 0.6 SHDN THRESHOLD HI-TO-LO (V) VIN = 3.2V 0.7 VIN = 2.4V VIN = 1.8V 0.
PAGE 4
LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 TYPICAL PERFOR A CE CHARACTERISTICS U W (TA = 25°C, CFLY = CIN = COUT = 2.2µF unless otherwise speciﬁed) Output Load Capability at 4% Below Regulation Load Regulation 400 3.35 LOAD CURRENT (mA) 3.25 VIN = 3.2V VIN = 1.8V 3.15 3.10 3.05 100 200 300 400 LOAD CURRENT (mA) TA = 25°C 300 250 TA = –45°C 200 6 100 0 1.5 500 2.5 3.0 2.0 SUPPLY VOLTAGE (V) 1.8 60 1.6 LTC3204B-3.3 1.4 56 1.2 54 1.0 52 0.8 0.6 LTC3204-3.3 0.
PAGE 5
LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 TYPICAL PERFOR A CE CHARACTERISTICS U W (LTC3204-5/LTC3204B-5 ONLY) (TA = 25°C, CFLY = CIN = COUT = 2.2µF unless otherwise speciﬁed) 5.20 500 450 VIN = 4.2V VIN = 3.6V 4.80 VIN = 2.7V 4.70 TA = 90°C 300 250 200 150 5 50 200 400 300 LOAD CURRENT (mA) 0 2.7 500 3.0 3.3 3.6 3.9 SUPPLY VOLTAGE (V) 2.8 2.4 2.0 LTC3204B-5 58 1.6 56 1.2 54 0.8 52 0.4 2.7 3 3.6 3.9 3.3 SUPPLY VOLTAGE (V) 4.2 0 4.
PAGE 6
LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 PI FU CTIO S U U U GND (Pin 1, 7): Ground. These pins should be tied to a ground plane for best performance. The exposed pad must be soldered to PCB ground to provide electrical contact and optimum thermal performance. VIN (Pin 2): Input Supply Voltage. VIN should be bypassed with a 1µF to 4.7µF low ESR ceramic capacitor. C+ (Pin 4): Flying Capacitor Positive Terminal. C– (Pin 5): Flying Capacitor Negative Terminal.
PAGE 7
U OPERATIO LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 (Refer to the Block Diagram) The LTC3204-3.3/LTC3204-5/LTC3204B-3.3/LTC3204B-5 use a switched capacitor charge pump to boost VIN to a regulated output voltage. Regulation is achieved by sensing the output voltage through an internal resistor divider and modulating the charge pump output current based on the error signal. A 2-phase nonoverlapping clock activates the charge pump switches.
PAGE 8
LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 APPLICATIO S I FOR ATIO U U U The power efﬁciency (η) of the LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 is similar to that of a linear regulator with an effective input voltage of twice the actual input voltage. This occurs because the input current for a voltage doubling charge pump is approximately twice the output current.
PAGE 9
LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 APPLICATIO S I FOR ATIO U W U U where f OSC is the oscillator frequency (typically 1.2MHz) and COUT is the value of output charge storage capacitor. Also, the value and style of the output capacitor can signiﬁcantly affect the stability of the LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5. As shown in the Block Diagram, the LTC3204-3.3/LTC3204-5/LTC3204B3.
PAGE 10
LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 APPLICATIO S I FOR ATIO U W U U Ceramic Capacitors Ceramic capacitors of different materials lose their capacitance with higher temperature and voltage at different rates. For example, a capacitor made of X5R or X7R material will retain most of its capacitance from –40°C to 85°C whereas a Z5U or Y5V style capacitor will lose considerable capacitance over that range.
PAGE 11
LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 APPLICATIO S I FOR ATIO U W U U This can be achieved from a printed circuit board layout with a solid ground plane and a good connection to the ground pins of LTC3204-3.3/LTC3204-5/LTC3204B-3.3/ LTC3204B-5 and the exposed pad of the DFN package. Operation out of this curve will cause the junction temperature to exceed 160°C which may trigger the thermal shutdown. 3.0 POWER DISSIPATION (W) 2.5 2.0 1.5 1.0 0.
PAGE 12
LTC3204-3.3/LTC3204-5/ LTC3204B-3.3/LTC3204B-5 TYPICAL APPLICATIO S U Regulated 3.3V Output 2.2µF 2 VIN 1.8V TO 4.5V 2.2µF 1, 7 6 OFF ON 4 C+ 3 VOUT 5 C– VIN VOUT 3.3V 2.2µF LTC3204-3.3/ LTC3204B-3.3 GND SHDN 3204 TA02 Lithium-Ion Battery to 5V White or Blue LED Driver 2.2µF 5 2 3V TO 4.4V Li-Ion BATTERY ON OFF 2.2µF C– VIN 4 C+ 3 VOUT DRIVE UP TO 5 LEDS 6 SHDN (APPLY PWM WAVEFORM FOR ADJUSTABLE BRIGHTNESS CONTROL) 100Ω 2.