MAX1577ZETA-T Maxim Integrated Products, MAX1577ZETA-T Datasheet - Page 4

• Manufacturer Part Number: MAX1577ZETA-T
• Description: Charge Pumps
• Manufacturer: Maxim Integrated Products

Specifications of MAX1577ZETA-T

• Function: Step Up, Step Down
• Output Voltage: 5.1 V
• Output Current: 1200 mA
• Maximum Operating Temperature: + 85 C
• Package / Case: TDFN-8 EP
• Minimum Operating Temperature: - 40 C
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

1.2A White LED Regulating Charge Pump for
Camera Flashes and Movie Lights
(V
4
IN
1200
1000
800
600
400
200
_______________________________________________________________________________________
225
220
215
210
205
200
= 3.6V, circuit of Figure 2, R
0
-40
0
LED CURRENT vs. PWM DUTY CYCLE
R
EN1 LOW
EN2 HIGH
LED CURRENT vs. TEMPERATURE
CS
= 0.27Ω
-15
20
V
TEMPERATURE (°C)
DUTY CYCLE (%)
V
OUT
V
CS
IN
40
10
TYPICAL OPERATING WAVEFORMS
60
35
R
EN1 PWM
EN2 HIGH
CS
CS
80
60
= 0.27Ω
IN 2x MODE
= 0.27Ω, Luxeon LXCL-PWF1 LED, T
400ns/div
100
85
Typical Operating Characteristics (continued)
80
70
60
50
40
30
20
10
MAX1577 toc10
1.2
1.0
0.8
0.6
0.4
0.2
0
0
2.7
0.2
EN1 HIGH, EN2 LOW
EFFICIENCY vs. SUPPLY VOLTAGE
3.1
50mV/div
(AC-COUPLED)
50mV/div
(AC-COUPLED)
50mV/div
(AC-COUPLED)
WITH PWM DIMMING
LED CURRENT vs. R
0.4
3.5
SUPPLY VOLTAGE (V)
50%
EN1 LOW, EN2 HIGH
EN1 AND EN2 HIGH
3.9
R
25%
CS
0.6
(Ω)
4.3
75%
A
= +25°C, unless otherwise noted.)
4.7
R
EN1 PWM
EN2 HIGH
0.8
CS
CS
V
V
V
EN1,
I
EN2
LED
LED
= 0.27Ω
5.1
STARTUP AND SHUTDOWN RESPONSE
5.5
1.0
V
V
V
I
V
OUT
EN1
LED
LED
V
CS
IN
400µs/div
TYPICAL OPERATING WAVEFORMS
DIMMING RESPONSE
IN 1x MODE
100µs/div
400ns/div
MAX1577 toc11
2V/div
2V/div
0V
0mA
500mA/div
MAX1577 toc14
MAX1577 toc09
2V/div
2V/div
0V
0mA
50mV/div
(AC-COUPLED)
50mV/div
(AC-COUPLED)
50mV/div
(AC-COUPLED)
500mA/div