ZLED7012ZI1R ZMDI, ZLED7012ZI1R Datasheet - Page 11

• Manufacturer Part Number: ZLED7012ZI1R
• Description: LED Lighting Drivers LED driver
• Manufacturer: ZMDI

Specifications of ZLED7012ZI1R

• Rohs: yes
• Input Voltage: 2.8 V to 5.5 V
• Maximum Supply Current: 1 mA
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: uTQFN-12
• Minimum Operating Temperature: - 40 C

2.6.
The ZLED7012 detects the rising edges of the control signal input on the EN/SET pin via an internal counter and decodes the
signal into one of the 14 current level settings given in Table 2.1. The control signal timing can vary (even during a program-
ming cycle), and its frequency can range from high data rates (e.g., 1MHz) to very low rates (e.g., 15kHz). (Also see section
2.4.) After sending the constant current level code data, the control system holds the EN/SET signal high for time T
minimum) so that the ZLED7012 latches the programmed current level code into the data register and the current level
becomes active as illustrated in Figure 2.1. The internal counter is then reset to zero to be ready for the next programming
cycle. This process is repeated for the next data sent by the control system for subsequent current level programming. See
section 2.4 regarding the low-current shutdown mode, which is entered when the EN/SET signal remains low for longer than
T
Figure 2.1
3
3.1.
The ZLED7012 charge pump operates at a fixed frequency of 1MHz (typical) to limit noise and harmonics and prevent genera-
tion of RF interference by the ZLED7012, which could affect operation of local communication devices, such as cell phones.
The soft-start feature also prevents noise transients caused by inrush currents due to charge pump start-up.
The ZLED7012 has significantly lower back-injected noise at the input pin of the charge pump (typically 60mV peak-to-peak),
compared to inductor-based DC/DC boost converter solutions for white LED backlight applications (typically 10 times higher).
3.2.
The ZLED7012 includes an on-board temperature sensing circuit that shuts down the ZLED7012 and turns off its outputs if the
die junction temperature exceeds 160°C (typical).
OFF
Data Sheet
November 9, 2010
ZLED7012
Low-Voltage Four-Channel LED Driver
(500μs minimum).
Operating Conditions
PCC Serial Digital Interface
RF Noise Reduction
ZLED7012 Thermal Protection
PCC Serial Digital Interface Signal Timing
Data Reg
EN/SET
I
© 2010 Zentrum Mikroelektronik Dresden AG — Rev. 1.0
All rights reserved. The material contained herein may not be reproduced, adapted, merged, translated, stored, or used without
the prior written consent of the copyright owner. The information furnished in this publication is subject to changes without notice.
OUT
1
2
T
LO
n
1
T
HI
n= 14
T
LAT
n
T
OFF
0
11 of 15
LAT
(500μs