MAX1885EUP-T Maxim Integrated, MAX1885EUP-T Datasheet - Page 11
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MAX1885EUP-T
Manufacturer Part Number
MAX1885EUP-T
Description
LCD Drivers Quad-Output TFT LCD DC-DC Converter with Buffer
Manufacturer
Maxim Integrated
Datasheet
1.MAX1882EUG.pdf
(39 pages)
Specifications of MAX1885EUP-T
Maximum Operating Temperature
+ 85 C
Minimum Operating Temperature
- 40 C
Package / Case
TSSOP-20
Mounting Style
SMD/SMT
(Circuit of Figure 1, V
BUF+ = FLTSET = TGND = PGND = GND, T
Maxim Integrated
-10V
20V
10V
20V
-5V
5V
8V
2V
0
0
0
A. V
B. RDY, 5V/div
C. POSITIVE CHARGE PUMP = V
D. STEP-UP CONVERTER: V
E. NEGATIVE CHARGE PUMP: V
A. V
B. V
C. V
MAIN
NEG
SHDN
POS
RIPPLE VOLTAGE WAVEFORMS
= -5V, I
= 20V, I
= 8V, I
= O TO 2V, 2V/div
POWER-UP SEQUENCE
NEG
MAIN
POS
= 10mA, 20mV/div
= 5mA, 20mV/div
= 200mA, 10mV/div
2ms/div
1µs/div
MAIN
IN
NEG
POS
= 8V, R
= -5V, R
= +3.3V, SHDN = IN, V
= 20V, R
LOAD
MAX1778 toc16
MAX1778 toc19
LOAD
LOAD
= 40Ω, 10V/div
= 500Ω, 10V/div
= 4kΩ, 10V/div
A
B
C
D
E
A
B
C
A
= +25°C.)
0.5A
20V
10V
-5V
6V
4V
Typical Operating Characteristics (continued)
2V
8V
2V
4V
0
MAX1778/MAX1880–MAX1885
0
0
0
0
A. V
B. V
C. INDUCTOR CURRENT, 500mA/div
R
A. RDY, 2V/div
B. POSITIVE CHARGE PUMP, V
C. STEP-UP CONVERTER: V
D. NEGATIVE CHARGE PUMP, V
LOAD
Quad-Output TFT LCD DC/DC
SHDN
MAIN
= 400Ω
MAIN
SOFT-START (LIGHT LOAD)
= 8V, 2V/div
= O TO 2V, 2V/div
(CIRCUIT OF FIGURE 10)
STEP-UP CONVERTER
POWER-UP SEQUENCE
= V
1ms/div
1ms/div
SUPP
Converters with Buffer
MAIN(SYS)
POS(SYS)
NEG
= V
= -5V, -5V/div
= 8V, 10V/div
MAX1778 toc17
SUPN
= 20V, 10V/div
MAX1778 toc20
= V
A
B
C
A
B
C
D
SUPB
1.0A
0.5A
10V
4V
2V
5V
5V
6V
4V
2V
8V
0
0
0
0
0
= V
A. RDY, 2V/div
B. GATE OF N-CH MOSFET, 5V/div
C. STEP-UP CONVERTER, V
A. V
B. V
C. INDUCTOR CURRENT, 500mA/div
R
LOAD
V
SHDN
MAIN
POWER-UP INTO SHORT-CIRCUIT
MAIN(SYS)
SUPL
= 20Ω
SOFT-START (HEAVY LOAD)
= 8V, 2V/div
= O TO 2V, 2V/div
(CIRCUIT OF FIGURE 10)
STEP-UP CONVERTER
= GND
= 8V, BUF- = BUFOUT,
100µs/div
1ms/div
MAIN(START)
= 8V, 5V/div
MAX1778 toc18
MAX1778 toc21
A
B
C
A
B
C
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